Next Issue
Previous Issue

Table of Contents

Biomolecules, Volume 8, Issue 2 (June 2018)

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Cover Story (view full-size image) The rapamycin-sensitive TOR kinase, an essential regulator of cell growth, assembles into two [...] Read more.
View options order results:
result details:
Displaying articles 1-29
Export citation of selected articles as:
Open AccessReview Calcium-Binding Proteins with Disordered Structure and Their Role in Secretion, Storage, and Cellular Signaling
Biomolecules 2018, 8(2), 42; https://doi.org/10.3390/biom8020042
Received: 25 May 2018 / Revised: 12 June 2018 / Accepted: 14 June 2018 / Published: 19 June 2018
Viewed by 616 | PDF Full-text (646 KB) | HTML Full-text | XML Full-text
Abstract
Calcium is one of the most important second messengers and its intracellular signaling regulates many aspects of cell physiology. Calcium ions, like phosphate ions, are highly charged and thus are able to alter protein conformation upon binding; thereby they constitute key factors in
[...] Read more.
Calcium is one of the most important second messengers and its intracellular signaling regulates many aspects of cell physiology. Calcium ions, like phosphate ions, are highly charged and thus are able to alter protein conformation upon binding; thereby they constitute key factors in signal transduction. One of the most common calcium-binding structural motifs is the EF-hand, a well-defined helix-loop-helix structural domain, present in many calcium-binding proteins (CBPs). Nonetheless, some CBPs contain non-canonical, disordered motifs, which usually bind calcium with high capacity and low affinity, and which represent a subset of proteins with specific functions, but these functions rarely involve signaling. When compared with phosphorylation-mediated signal transduction, the role of intrinsic disorder in calcium signaling is significantly less prominent and not direct. The list of known examples of intrinsically disordered CBPs is relatively short and the disorder in these examples seems to be linked to secretion and storage. Calcium-sensitive phosphatase calcineurin is an exception, but it represents an example of transient disorder, which is, nevertheless, vital to the functioning of this protein. The underlying reason for the different role of disordered proteins in the two main cellular signaling systems appears to be linked to the gradient of calcium concentration, present in all living cells. Full article
(This article belongs to the Special Issue Calcium Binding Proteins: Structure, Properties, Functions)
Figures

Figure 1

Open AccessArticle Pinocembrin–Lecithin Complex: Characterization, Solubilization, and Antioxidant Activities
Biomolecules 2018, 8(2), 41; https://doi.org/10.3390/biom8020041
Received: 14 May 2018 / Revised: 14 June 2018 / Accepted: 18 June 2018 / Published: 19 June 2018
Viewed by 598 | PDF Full-text (3121 KB) | HTML Full-text | XML Full-text
Abstract
Pinocembrin is a natural flavonoid compound which is capable of antioxidant, antibacterial, anti-inflammatory, and antineoplastic activities. The present study aimed to enhance the solubility and antioxidant activities of pinocembrin by complex formation with lecithin. The physicochemical characteristics of pinocembrin–lecithin complex were analyzed by
[...] Read more.
Pinocembrin is a natural flavonoid compound which is capable of antioxidant, antibacterial, anti-inflammatory, and antineoplastic activities. The present study aimed to enhance the solubility and antioxidant activities of pinocembrin by complex formation with lecithin. The physicochemical characteristics of pinocembrin–lecithin complex were analyzed by ultraviolet (UV), fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and solubility assay, and the antioxidant activities of pinocembrin–lecithin complex were evaluated via radical scavenging capacities for 2,2′-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), hydroxyl, and superoxide-anion. The results indicated that pinocembrin complex with lecithin could significantly improve the solubility of pinocembrin in water and n-octane, the pinocembrin–lecithin complex displayed no characteristic endothermic peak and the appearance of amorphous state, compared to the pinocembrin, and no new covalent bond was produced in the pinocembrin and lecithin compound. It was demonstrated that the antioxidant activities of pinocembrin were obviously enhanced by the complex with lecithin, and the scavenging capacities for hydroxyl radical, DPPH, superoxide-anion radical, and ABTS radical of pinocembrin–lecithin complex were 82.44 ± 2.21%, 40.07 ± 1.32%, 59.15 ± 0.86%, and 24.73 ± 1.04% at 1.0 mg/mL, respectively. It suggested that the pinocembrin–lecithin complex had a great potential application prospect in the healthcare industry and in clinical practice. Full article
Figures

Graphical abstract

Open AccessFeature PaperReview Nontraditional Cardiovascular Biomarkers and Risk Factors: Rationale and Future Perspectives
Biomolecules 2018, 8(2), 40; https://doi.org/10.3390/biom8020040
Received: 15 May 2018 / Revised: 11 June 2018 / Accepted: 13 June 2018 / Published: 15 June 2018
Cited by 2 | Viewed by 583 | PDF Full-text (254 KB) | HTML Full-text | XML Full-text
Abstract
The primary prevention of cardiovascular (CV) disease depends on the capacity to identify subjects at higher risk long before the occurrence of CV clinical manifestations. Traditional risk factors do not cover fully prediction of individual risk. Moreover, there is an area of gray
[...] Read more.
The primary prevention of cardiovascular (CV) disease depends on the capacity to identify subjects at higher risk long before the occurrence of CV clinical manifestations. Traditional risk factors do not cover fully prediction of individual risk. Moreover, there is an area of gray for patients at intermediate CV risk, which offers wide margins of improvement. These observations highlight the need for new additive tools for a more accurate risk stratification. An increasing number of candidate biomarkers have been identified to predict CV risk and events, although they generally give only a moderate increase when added to currently available predictive scores. The approach utilizing a relative small number of biomarkers in multiple combinations, but only weakly related to each other or unrelated, thus belonging to independent-pathways, and so able to catch the multidimensional characteristic of atherosclerosis, appears promising. We discuss vitamin D and bone turnover biomarkers, hepatitis C virus, and psycho-emotional factors that may reflect alternative pathways over those generally considered for atherosclerosis (e.g., aspects directly related to inflammation and thrombosis). These new biomarkers could facilitate a more accurate assessment of CV risk stratification if incorporated in the current risk assessment algorithms. Full article
(This article belongs to the Special Issue Biomolecules for Translational Approaches in Cardiology)
Open AccessArticle Arabidopsis Transcription Factor MYB102 Increases Plant Susceptibility to Aphids by Substantial Activation of Ethylene Biosynthesis
Biomolecules 2018, 8(2), 39; https://doi.org/10.3390/biom8020039
Received: 22 April 2018 / Revised: 4 June 2018 / Accepted: 5 June 2018 / Published: 7 June 2018
Viewed by 904 | PDF Full-text (3287 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Induction of ethylene biosynthesis by aphids increases the susceptibility of several plant species to aphids. Recent studies have indicated that some MYB transcription factors regulate the phloem-based defense against aphid infestation by modulating ethylene (ET) signaling. Arabidopsis MYB102 has previously been shown to
[...] Read more.
Induction of ethylene biosynthesis by aphids increases the susceptibility of several plant species to aphids. Recent studies have indicated that some MYB transcription factors regulate the phloem-based defense against aphid infestation by modulating ethylene (ET) signaling. Arabidopsis MYB102 has previously been shown to be induced by wound signaling and regulate defense response against chewing insects. However, it remains unclear whether Arabidopsis MYB102 takes part in the defense response of plants to aphids. Here, we investigated the function of MYB102 in the response of Arabidopsis to aphid infestation. Arabidopsis MYB102 was primarily expressed in vascular tissues, and its transcription was remarkably induced by green peach aphids (GPA; Myzus persicae). The results of RNA-Sequencing revealed that overexpression of MYB102 in Arabidopsis promoted ET biosynthesis by upregulation of some 1-aminocyclopropane-1-carboxylate synthase (ACS) genes, which are rate-limiting enzymes of the ET-synthetic pathway. Enhanced ET levels led to reduced Arabidopsis resistance to GPA. Furthermore, dominant suppression of MYB102 inhibited aphid-induced increase of ET levels in Arabidopsis. In agreement with a negative regulatory role for ET in aphid defense responses, the MYB102-overexpressing lines were more susceptible to GPA than wild-type (WT) plants. Overexpression of MYB102 in Arabidopsis obviously repressed aphid-induced callose deposition. Conversely, overexpression of MYB102 failed to increase aphid susceptibility in both the ET-insensitive mutants and plants treated with inhibitors of ET signaling pathways, demonstrating that the ET was critical for promoting aphid performance conferred by overexpression of MYB102. Collectively, our findings indicate that the Arabidopsis MYB102 increases host susceptibility to GPA through the ET-dependent signaling pathways. Full article
Figures

Figure 1

Open AccessReview Turning Uridines around: Role of rRNA Pseudouridylation in Ribosome Biogenesis and Ribosomal Function
Biomolecules 2018, 8(2), 38; https://doi.org/10.3390/biom8020038
Received: 30 April 2018 / Revised: 28 May 2018 / Accepted: 31 May 2018 / Published: 5 June 2018
Cited by 2 | Viewed by 963 | PDF Full-text (601 KB) | HTML Full-text | XML Full-text
Abstract
Ribosomal RNA (rRNA) is extensively edited through base methylation and acetylation, 2′-O-ribose methylation and uridine isomerization. In human rRNA, 95 uridines are predicted to by modified to pseudouridine by ribonucleoprotein complexes sharing four core proteins and differing for a RNA sequence guiding the
[...] Read more.
Ribosomal RNA (rRNA) is extensively edited through base methylation and acetylation, 2′-O-ribose methylation and uridine isomerization. In human rRNA, 95 uridines are predicted to by modified to pseudouridine by ribonucleoprotein complexes sharing four core proteins and differing for a RNA sequence guiding the complex to specific residues to be modified. Most pseudouridylation sites are placed within functionally important ribosomal domains and can influence ribosomal functional features. Information obtained so far only partially explained the degree of regulation and the consequences of pseudouridylation on ribosomal structure and function in different physiological and pathological conditions. This short review focuses on the available evidence in this topic, highlighting open questions in the field and perspectives that the development of emerging techniques is offering. Full article
(This article belongs to the Special Issue rRNA Biology)
Figures

Figure 1

Open AccessCommunication Simple Analysis of Lipid Inhibition Activity on an Adipocyte Micro-Cell Pattern Chip
Biomolecules 2018, 8(2), 37; https://doi.org/10.3390/biom8020037
Received: 5 April 2018 / Revised: 25 May 2018 / Accepted: 31 May 2018 / Published: 4 June 2018
Viewed by 803 | PDF Full-text (2549 KB) | HTML Full-text | XML Full-text
Abstract
Polydimethyl-siloxane (PDMS) is often applied to fabricate cell chips. In this study, we fabricated an adipocyte microcell pattern chips using PDMS to analyze the inhibition activity of lipid droplets in mouse embryo fibroblast cells (3T3-L1) with anti-obesity agents. To form the PDMS based
[...] Read more.
Polydimethyl-siloxane (PDMS) is often applied to fabricate cell chips. In this study, we fabricated an adipocyte microcell pattern chips using PDMS to analyze the inhibition activity of lipid droplets in mouse embryo fibroblast cells (3T3-L1) with anti-obesity agents. To form the PDMS based micropattern, we applied the micro-contact printing technique using PDMS micro-stamps that had been fabricated by conventional soft lithography. This PDMS micro-pattern enabled the selective growth of 3T3-L1 cells onto the specific region by preventing cell adhesion on the PDMS region. It then allowed growth of the 3T3-L1 cells in the chip for 10 days and confirmed that lipid droplets were formed in the 3T3-L1 cells. After treatment of orlistat and quercetin were treated in an adipocyte micro-cell pattern chip with 3T3-L1 cells for six days, we found that orlistat and quercetin exhibited fat inhibition capacities of 19.3% and 24.4% from 0.2 μM of lipid droplets in 3T3-L1 cells. In addition, we conducted a direct quantitative analysis of 3T3-L1 cell differentiation using Oil Red O staining. In conclusion, PDMS-based adipocyte micro-cell pattern chips may contribute to the development of novel bioactive compounds. Full article
(This article belongs to the Special Issue Obesity and Hormones)
Figures

Figure 1

Open AccessArticle Redesigning TOR Kinase to Explore the Structural Basis for TORC1 and TORC2 Assembly
Biomolecules 2018, 8(2), 36; https://doi.org/10.3390/biom8020036
Received: 5 May 2018 / Revised: 25 May 2018 / Accepted: 25 May 2018 / Published: 1 June 2018
Viewed by 947 | PDF Full-text (11919 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
TOR is a serine/threonine protein kinase that assembles into distinct TOR Complexes 1 and 2 (TORC1 or TORC2) to regulate cell growth. In mammalian cells, a single mTOR incorporates stably into mTORC1 and mTORC2. By contrast, in Saccharomyces cerevisiae, two highly similar
[...] Read more.
TOR is a serine/threonine protein kinase that assembles into distinct TOR Complexes 1 and 2 (TORC1 or TORC2) to regulate cell growth. In mammalian cells, a single mTOR incorporates stably into mTORC1 and mTORC2. By contrast, in Saccharomyces cerevisiae, two highly similar Tor1 and Tor2 proteins exist, where Tor1 assembles exclusively into TORC1 and Tor2 assembles preferentially into TORC2. To gain insight into TOR complex assembly, we used this bifurcation in yeast to identify structural elements within Tor1 and Tor2 that govern their complex specificity. We have identified a concise region of ~500 amino acids within the N-terminus of Tor2, which we term the Major Assembly Specificity (MAS) domain, that is sufficient to confer significant TORC2 activity when placed into an otherwise Tor1 protein. Consistently, introduction of the corresponding MAS domain from Tor1 into an otherwise Tor2 is sufficient to confer stable association with TORC1-specific components. Remarkably, much like mTOR, this latter chimera also retains stable interactions with TORC2 components, indicating that determinants throughout Tor1/Tor2 contribute to complex specificity. Our findings are in excellent agreement with recent ultrastructural studies of TORC1 and TORC2, where the MAS domain is involved in quaternary interactions important for complex formation and/or stability. Full article
(This article belongs to the Special Issue TOR Signaling Pathway)
Figures

Figure 1

Open AccessFeature PaperArticle Protein Expression Profile of Twenty-Week-Old Diabetic db/db and Non-Diabetic Mice Livers: A Proteomic and Bioinformatic Analysis
Biomolecules 2018, 8(2), 35; https://doi.org/10.3390/biom8020035
Received: 13 March 2018 / Revised: 27 May 2018 / Accepted: 29 May 2018 / Published: 1 June 2018
Viewed by 873 | PDF Full-text (1459 KB) | HTML Full-text | XML Full-text
Abstract
Type 2 diabetes mellitus is characterized by insulin resistance in the liver. Insulin is not only involved in carbohydrate metabolism, it also regulates protein synthesis. This work describes the expression of proteins in the liver of a diabetic mouse and identifies the metabolic
[...] Read more.
Type 2 diabetes mellitus is characterized by insulin resistance in the liver. Insulin is not only involved in carbohydrate metabolism, it also regulates protein synthesis. This work describes the expression of proteins in the liver of a diabetic mouse and identifies the metabolic pathways involved. Twenty-week-old diabetic db/db mice were hepatectomized, after which proteins were separated by 2D-Polyacrylamide Gel Electrophoresis (2D-PAGE). Spots varying in intensity were analyzed using mass spectrometry, and biological function was assigned by the Database for Annotation, Visualization and Integrated Discovery (DAVID) software. A differential expression of 26 proteins was identified; among these were arginase-1, pyruvate carboxylase, peroxiredoxin-1, regucalcin, and sorbitol dehydrogenase. Bioinformatics analysis indicated that many of these proteins are mitochondrial and participate in metabolic pathways, such as the citrate cycle, the fructose and mannose metabolism, and glycolysis or gluconeogenesis. In addition, these proteins are related to oxidation–reduction reactions and molecular function of vitamin binding and amino acid metabolism. In conclusion, the proteomic profile of the liver of diabetic mouse db/db exhibited mainly alterations in the metabolism of carbohydrates and nitrogen. These differences illustrate the heterogeneity of diabetes in its different stages and under different conditions and highlights the need to improve treatments for this disease. Full article
Figures

Figure 1

Open AccessReview Metabolomics in Radiation-Induced Biological Dosimetry: A Mini-Review and a Polyamine Study
Biomolecules 2018, 8(2), 34; https://doi.org/10.3390/biom8020034
Received: 5 April 2018 / Revised: 18 May 2018 / Accepted: 25 May 2018 / Published: 29 May 2018
Viewed by 685 | PDF Full-text (1007 KB) | HTML Full-text | XML Full-text
Abstract
In this study, we elucidate that polyamine metabolite is a powerful biomarker to study post-radiation changes. Metabolomics in radiation biodosimetry, the application of a metabolomics analysis to the field of radiobiology, promises to increase the understanding of biological responses by ionizing radiation (IR).
[...] Read more.
In this study, we elucidate that polyamine metabolite is a powerful biomarker to study post-radiation changes. Metabolomics in radiation biodosimetry, the application of a metabolomics analysis to the field of radiobiology, promises to increase the understanding of biological responses by ionizing radiation (IR). Radiation exposure triggers a complex network of molecular and cellular responses that impacts metabolic processes and alters the levels of metabolites. Such metabolites have potential as biomarkers for radiation dosimetry. Among metabolites, polyamine is one of many potential biomarkers to estimate radiation response. In addition, this review provides an opportunity for the understanding of a radiation metabolomics in biodosimetry and a polyamine case study. Full article
Figures

Graphical abstract

Open AccessArticle Protein Solvent-Accessibility Prediction by a Stacked Deep Bidirectional Recurrent Neural Network
Biomolecules 2018, 8(2), 33; https://doi.org/10.3390/biom8020033
Received: 21 April 2018 / Revised: 18 May 2018 / Accepted: 22 May 2018 / Published: 25 May 2018
Viewed by 644 | PDF Full-text (729 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Residue solvent accessibility is closely related to the spatial arrangement and packing of residues. Predicting the solvent accessibility of a protein is an important step to understand its structure and function. In this work, we present a deep learning method to predict residue
[...] Read more.
Residue solvent accessibility is closely related to the spatial arrangement and packing of residues. Predicting the solvent accessibility of a protein is an important step to understand its structure and function. In this work, we present a deep learning method to predict residue solvent accessibility, which is based on a stacked deep bidirectional recurrent neural network applied to sequence profiles. To capture more long-range sequence information, a merging operator was proposed when bidirectional information from hidden nodes was merged for outputs. Three types of merging operators were used in our improved model, with a long short-term memory network performing as a hidden computing node. The trained database was constructed from 7361 proteins extracted from the PISCES server using a cut-off of 25% sequence identity. Sequence-derived features including position-specific scoring matrix, physical properties, physicochemical characteristics, conservation score and protein coding were used to represent a residue. Using this method, predictive values of continuous relative solvent-accessible area were obtained, and then, these values were transformed into binary states with predefined thresholds. Our experimental results showed that our deep learning method improved prediction quality relative to current methods, with mean absolute error and Pearson’s correlation coefficient values of 8.8% and 74.8%, respectively, on the CB502 dataset and 8.2% and 78%, respectively, on the Manesh215 dataset. Full article
Figures

Figure 1

Open AccessArticle FMSP-Nanoparticles Induced Cell Death on Human Breast Adenocarcinoma Cell Line (MCF-7 Cells): Morphometric Analysis
Biomolecules 2018, 8(2), 32; https://doi.org/10.3390/biom8020032
Received: 9 April 2018 / Revised: 13 May 2018 / Accepted: 15 May 2018 / Published: 23 May 2018
Viewed by 1021 | PDF Full-text (3907 KB) | HTML Full-text | XML Full-text
Abstract
Currently, breast cancer treatment mostly revolves around radiation therapy and surgical interventions, but often these treatments do not provide satisfactory relief to the patients and cause unmanageable side-effects. Nanomaterials show promising results in treating cancer cells and have many advantages such as high
[...] Read more.
Currently, breast cancer treatment mostly revolves around radiation therapy and surgical interventions, but often these treatments do not provide satisfactory relief to the patients and cause unmanageable side-effects. Nanomaterials show promising results in treating cancer cells and have many advantages such as high biocompatibility, bioavailability and effective therapeutic capabilities. Interestingly, fluorescent magnetic nanoparticles have been used in many biological and diagnostic applications, but there is no report of use of fluorescent magnetic submicronic polymer nanoparticles (FMSP-nanoparticles) in the treatment of human breast cancer cells. In the present study, we tested the effect of FMSP-nanoparticles on human breast cancer cells (MCF-7). We tested different concentrations (1.25, 12.5 and 50 µg/mL) of FMSP-nanoparticles in MCF-7 cells and evaluated the nanoparticles response morphometrically. Our results revealed that FMSP-nanoparticles produced a concentration dependent effect on the cancer cells, a dose of 1.25 µg/mL produced no significant effect on the cancer cell morphology and cell death, whereas dosages of 12.5 and 50 µg/mL resulted in significant nuclear augmentation, disintegration, chromatic condensation followed by dose dependent cell death. Our results demonstrate that FMSP-nanoparticles induce cell death in MCF-7 cells and may be a potential anti-cancer agent for breast cancer treatment. Full article
Figures

Graphical abstract

Open AccessReview Anandamide Revisited: How Cholesterol and Ceramides Control Receptor-Dependent and Receptor-Independent Signal Transmission Pathways of a Lipid Neurotransmitter
Biomolecules 2018, 8(2), 31; https://doi.org/10.3390/biom8020031
Received: 3 April 2018 / Revised: 2 May 2018 / Accepted: 16 May 2018 / Published: 22 May 2018
Viewed by 880 | PDF Full-text (2520 KB) | HTML Full-text | XML Full-text
Abstract
Anandamide is a lipid neurotransmitter derived from arachidonic acid, a polyunsaturated fatty acid. The chemical differences between anandamide and arachidonic acid result in a slightly enhanced solubility in water and absence of an ionisable group for the neurotransmitter compared with the fatty acid.
[...] Read more.
Anandamide is a lipid neurotransmitter derived from arachidonic acid, a polyunsaturated fatty acid. The chemical differences between anandamide and arachidonic acid result in a slightly enhanced solubility in water and absence of an ionisable group for the neurotransmitter compared with the fatty acid. In this review, we first analyze the conformational flexibility of anandamide in aqueous and membrane phases. We next study the interaction of the neurotransmitter with membrane lipids and discuss the molecular basis of the unexpected selectivity of anandamide for cholesterol and ceramide from among other membrane lipids. We show that cholesterol behaves as a binding partner for anandamide, and that following an initial interaction mediated by the establishment of a hydrogen bond, anandamide is attracted towards the membrane interior, where it forms a molecular complex with cholesterol after a functional conformation adaptation to the apolar membrane milieu. The complex is then directed to the anandamide cannabinoid receptor (CB1) which displays a high affinity binding pocket for anandamide. We propose that cholesterol may regulate the entry and exit of anandamide in and out of CB1 by interacting with low affinity cholesterol recognition sites (CARC and CRAC) located in transmembrane helices. The mirror topology of cholesterol binding sites in the seventh transmembrane domain is consistent with the delivery, extraction and flip-flop of anandamide through a coordinated cholesterol-dependent mechanism. The binding of anandamide to ceramide illustrates another key function of membrane lipids which may occur independently of protein receptors. Interestingly, ceramide forms a tight complex with anandamide which blocks the degradation pathway of both lipids and could be exploited for anti-cancer therapies. Full article
(This article belongs to the Special Issue Cellular Membrane Domains and Organization)
Figures

Figure 1

Open AccessReview Brownian Motion at Lipid Membranes: A Comparison of Hydrodynamic Models Describing and Experiments Quantifying Diffusion within Lipid Bilayers
Biomolecules 2018, 8(2), 30; https://doi.org/10.3390/biom8020030
Received: 5 April 2018 / Revised: 7 May 2018 / Accepted: 16 May 2018 / Published: 22 May 2018
Viewed by 849 | PDF Full-text (3959 KB) | HTML Full-text | XML Full-text
Abstract
The capability of lipid bilayers to exhibit fluid-phase behavior is a fascinating property, which enables, for example, membrane-associated components, such as lipids (domains) and transmembrane proteins, to diffuse within the membrane. These diffusion processes are of paramount importance for cells, as they are
[...] Read more.
The capability of lipid bilayers to exhibit fluid-phase behavior is a fascinating property, which enables, for example, membrane-associated components, such as lipids (domains) and transmembrane proteins, to diffuse within the membrane. These diffusion processes are of paramount importance for cells, as they are for example involved in cell signaling processes or the recycling of membrane components, but also for recently developed analytical approaches, which use differences in the mobility for certain analytical purposes, such as in-membrane purification of membrane proteins or the analysis of multivalent interactions. Here, models describing the Brownian motion of membrane inclusions (lipids, peptides, proteins, and complexes thereof) in model bilayers (giant unilamellar vesicles, black lipid membranes, supported lipid bilayers) are summarized and model predictions are compared with the available experimental data, thereby allowing for evaluating the validity of the introduced models. It will be shown that models describing the diffusion in freestanding (Saffman-Delbrück and Hughes-Pailthorpe-White model) and supported bilayers (the Evans-Sackmann model) are well supported by experiments, though only few experimental studies have been published so far for the latter case, calling for additional tests to reach the same level of experimental confirmation that is currently available for the case of freestanding bilayers. Full article
(This article belongs to the Special Issue Cellular Membrane Domains and Organization)
Figures

Figure 1

Open AccessFeature PaperArticle Critical Assessment of Methods to Quantify Biofilm Growth and Evaluate Antibiofilm Activity of Host Defence Peptides
Biomolecules 2018, 8(2), 29; https://doi.org/10.3390/biom8020029
Received: 12 April 2018 / Revised: 11 May 2018 / Accepted: 17 May 2018 / Published: 21 May 2018
Viewed by 1309 | PDF Full-text (6591 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Biofilms are multicellular communities of bacteria that can adhere to virtually any surface. Bacterial biofilms are clinically relevant, as they are responsible for up to two-thirds of hospital acquired infections and contribute to chronic infections. Troublingly, the bacteria within a biofilm are adaptively
[...] Read more.
Biofilms are multicellular communities of bacteria that can adhere to virtually any surface. Bacterial biofilms are clinically relevant, as they are responsible for up to two-thirds of hospital acquired infections and contribute to chronic infections. Troublingly, the bacteria within a biofilm are adaptively resistant to antibiotic treatment and it can take up to 1000 times more antibiotic to kill cells within a biofilm when compared to planktonic bacterial cells. Identifying and optimizing compounds that specifically target bacteria growing in biofilms is required to address this growing concern and the reported antibiofilm activity of natural and synthetic host defence peptides has garnered significant interest. However, a standardized assay to assess the activity of antibiofilm agents has not been established. In the present work, we describe two simple assays that can assess the inhibitory and eradication capacities of peptides towards biofilms that are formed by both Gram-positive and negative bacteria. These assays are suitable for high-throughput workflows in 96-well microplates and they use crystal violet staining to quantify adhered biofilm biomass as well as tetrazolium chloride dye to evaluate the metabolic activity of the biofilms. The effect of media composition on the readouts of these biofilm detection methods was assessed against two strains of Pseudomonas aeruginosa (PAO1 and PA14), as well as a methicillin resistant strain of Staphylococcus aureus. Our results demonstrate that media composition dramatically alters the staining patterns that were obtained with these dye-based methods, highlighting the importance of establishing appropriate biofilm growth conditions for each bacterial species to be evaluated. Confocal microscopy imaging of P. aeruginosa biofilms grown in flow cells revealed that this is likely due to altered biofilm architecture under specific growth conditions. The antibiofilm activity of several antibiotics and synthetic peptides were then evaluated under both inhibition and eradication conditions to illustrate the type of data that can be obtained using this experimental setup. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Development, Conjugation, and Beyond)
Figures

Figure 1

Open AccessArticle Determination of the Membrane Environment of CD59 in Living Cells
Biomolecules 2018, 8(2), 28; https://doi.org/10.3390/biom8020028
Received: 15 March 2018 / Revised: 24 April 2018 / Accepted: 14 May 2018 / Published: 17 May 2018
Cited by 1 | Viewed by 766 | PDF Full-text (1299 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The organization and dynamics of proteins and lipids in the plasma membrane, and their role in membrane functionality, have been subject of a long-lasting debate. Specifically, it is unclear to what extent membrane proteins are affected by their immediate lipid environment and vice
[...] Read more.
The organization and dynamics of proteins and lipids in the plasma membrane, and their role in membrane functionality, have been subject of a long-lasting debate. Specifically, it is unclear to what extent membrane proteins are affected by their immediate lipid environment and vice versa. Studies on model membranes and plasma membrane vesicles indicated preferences of proteins for lipid phases characterized by different acyl chain order; however, whether such phases do indeed exist in live cells is still not known. Here, we refine a previously developed micropatterning approach combined with single molecule tracking to quantify the influence of the glycosylphosphatidylinositol-anchored (GPI-anchored) protein CD59 on its molecular environment directly in the live cell plasma membrane. We find that locally enriched and immobilized CD59 presents obstacles to the diffusion of fluorescently labeled lipids with a different phase-partitioning behavior independent of cell cholesterol levels and type of lipid. Our results give no evidence for either specific binding of the lipids to CD59 or the existence of nanoscopic ordered membrane regions associated with CD59. Full article
(This article belongs to the Special Issue Cellular Membrane Domains and Organization)
Figures

Figure 1

Open AccessReview Antibiofilm Peptides and Peptidomimetics with Focus on Surface Immobilization
Biomolecules 2018, 8(2), 27; https://doi.org/10.3390/biom8020027
Received: 25 April 2018 / Revised: 12 May 2018 / Accepted: 14 May 2018 / Published: 16 May 2018
Cited by 2 | Viewed by 1462 | PDF Full-text (1640 KB) | HTML Full-text | XML Full-text
Abstract
Bacterial biofilms pose a major threat to public health, as they are associated with at least two thirds of all infections. They are highly resilient and render conventional antibiotics inefficient. As a part of the innate immune system, antimicrobial peptides have drawn attention
[...] Read more.
Bacterial biofilms pose a major threat to public health, as they are associated with at least two thirds of all infections. They are highly resilient and render conventional antibiotics inefficient. As a part of the innate immune system, antimicrobial peptides have drawn attention within the last decades, as some of them are able to eradicate biofilms at sub-minimum inhibitory concentration (MIC) levels. However, peptides possess a number of disadvantages, such as susceptibility to proteolytic degradation, pH and/or salinity-dependent activity and loss of activity due to binding to serum proteins. Hence, proteolytically stable peptidomimetics were designed to overcome these drawbacks. This paper summarizes the current peptide and peptidomimetic strategies for combating bacteria-associated biofilm infections, both in respect to soluble and surface-functionalized solutions. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Development, Conjugation, and Beyond)
Figures

Figure 1

Open AccessFeature PaperArticle Membrane Remodeling as a Key Player of the Hepatotoxicity Induced by Co-Exposure to Benzo[a]pyrene and Ethanol of Obese Zebrafish Larvae
Biomolecules 2018, 8(2), 26; https://doi.org/10.3390/biom8020026
Received: 6 April 2018 / Revised: 4 May 2018 / Accepted: 4 May 2018 / Published: 14 May 2018
Viewed by 877 | PDF Full-text (2262 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The rise in prevalence of non-alcoholic fatty liver disease (NAFLD) constitutes an important public health concern worldwide. Including obesity, numerous risk factors of NAFLD such as benzo[a]pyrene (B[a]P) and ethanol have been identified as modifying the physicochemical properties of the plasma membrane in
[...] Read more.
The rise in prevalence of non-alcoholic fatty liver disease (NAFLD) constitutes an important public health concern worldwide. Including obesity, numerous risk factors of NAFLD such as benzo[a]pyrene (B[a]P) and ethanol have been identified as modifying the physicochemical properties of the plasma membrane in vitro thus causing membrane remodeling—changes in membrane fluidity and lipid-raft characteristics. In this study, the possible involvement of membrane remodeling in the in vivo progression of steatosis to a steatohepatitis-like state upon co-exposure to B[a]P and ethanol was tested in obese zebrafish larvae. Larvae bearing steatosis as the result of a high-fat diet were exposed to ethanol and/or B[a]P for seven days at low concentrations coherent with human exposure in order to elicit hepatotoxicity. In this condition, the toxicant co-exposure raised global membrane order with higher lipid-raft clustering in the plasma membrane of liver cells, as evaluated by staining with the fluoroprobe di-4-ANEPPDHQ. Involvement of this membrane’s remodeling was finally explored by using the lipid-raft disruptor pravastatin that counteracted the effects of toxicant co-exposure both on membrane remodeling and toxicity. Overall, it can be concluded that B[a]P/ethanol co-exposure can induce in vivo hepatotoxicity via membrane remodeling which could be considered as a good target mechanism for developing combination therapy to deal with steatohepatitis. Full article
(This article belongs to the Special Issue Cellular Membrane Domains and Organization)
Figures

Figure 1

Open AccessArticle Structural Transition and Antibody Binding of EBOV GP and ZIKV E Proteins from Pre-Fusion to Fusion-Initiation State
Biomolecules 2018, 8(2), 25; https://doi.org/10.3390/biom8020025
Received: 4 April 2018 / Revised: 4 May 2018 / Accepted: 7 May 2018 / Published: 10 May 2018
Cited by 1 | Viewed by 1441 | PDF Full-text (7367 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Membrane fusion proteins are responsible for viral entry into host cells—a crucial first step in viral infection. These proteins undergo large conformational changes from pre-fusion to fusion-initiation structures, and, despite differences in viral genomes and disease etiology, many fusion proteins are arranged as
[...] Read more.
Membrane fusion proteins are responsible for viral entry into host cells—a crucial first step in viral infection. These proteins undergo large conformational changes from pre-fusion to fusion-initiation structures, and, despite differences in viral genomes and disease etiology, many fusion proteins are arranged as trimers. Structural information for both pre-fusion and fusion-initiation states is critical for understanding virus neutralization by the host immune system. In the case of Ebola virus glycoprotein (EBOV GP) and Zika virus envelope protein (ZIKV E), pre-fusion state structures have been identified experimentally, but only partial structures of fusion-initiation states have been described. While the fusion-initiation structure is in an energetically unfavorable state that is difficult to solve experimentally, the existing structural information combined with computational approaches enabled the modeling of fusion-initiation state structures of both proteins. These structural models provide an improved understanding of four different neutralizing antibodies in the prevention of viral host entry. Full article
Figures

Figure 1

Open AccessArticle Pharmaceutical Machine Learning: Virtual High-Throughput Screens Identifying Promising and Economical Small Molecule Inhibitors of Complement Factor C1s
Biomolecules 2018, 8(2), 24; https://doi.org/10.3390/biom8020024
Received: 19 February 2018 / Revised: 26 April 2018 / Accepted: 27 April 2018 / Published: 7 May 2018
Viewed by 1459 | PDF Full-text (1227 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
When excessively activated, C1 is insufficiently regulated, which results in tissue damage. Such tissue damage causes the complement system to become further activated to remove the resulting tissue damage, and a vicious cycle of activation/tissue damage occurs. Current Food and Drug Administration approved
[...] Read more.
When excessively activated, C1 is insufficiently regulated, which results in tissue damage. Such tissue damage causes the complement system to become further activated to remove the resulting tissue damage, and a vicious cycle of activation/tissue damage occurs. Current Food and Drug Administration approved treatments include supplemental recombinant C1 inhibitor, but these are extremely costly and a more economical solution is desired. In our work, we have utilized an existing data set of 136 compounds that have been previously tested for activity against C1. Using these compounds and the activity data, we have created models using principal component analysis, genetic algorithm, and support vector machine approaches to characterize activity. The models were then utilized to virtually screen the 72 million compound PubChem repository. This first round of virtual high-throughput screening identified many economical and promising inhibitor candidates, a subset of which was tested to validate their biological activity. These results were used to retrain the models and rescreen PubChem in a second round vHTS. Hit rates for the first round vHTS were 57%, while hit rates for the second round vHTS were 50%. Additional structure–property analysis was performed on the active and inactive compounds to identify interesting scaffolds for further investigation. Full article
(This article belongs to the Special Issue Machine Learning for Molecular Modelling in Drug Design)
Figures

Graphical abstract

Open AccessArticle Capture of Pb2+ and Cu2+ Metal Cations by Neisseria meningitidis-type Capsular Polysaccharides
Biomolecules 2018, 8(2), 23; https://doi.org/10.3390/biom8020023
Received: 16 April 2018 / Revised: 2 May 2018 / Accepted: 2 May 2018 / Published: 5 May 2018
Viewed by 1584 | PDF Full-text (2754 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Heavy metal pollution of water is a significant environmental and public health concern. Current biological strategies for heavy metal removal from water are performed using microbial biopolymers, including polysaccharides, that are already fully formed. This creates limitations in adapting polysaccharides to increase binding
[...] Read more.
Heavy metal pollution of water is a significant environmental and public health concern. Current biological strategies for heavy metal removal from water are performed using microbial biopolymers, including polysaccharides, that are already fully formed. This creates limitations in adapting polysaccharides to increase binding affinity for specific metals. We propose that altering the specificity of polysaccharide-producing enzymes could be beneficial to improving metal capture by modified polysaccharides. We assess binding of Cu2+ and Pb2+ metal cations to Neisseria meningitidis-type polysaccharides. All concentrations of metal cations tested were able to completely bind to colominic acid. This polymer is equivalent to the capsular polysaccharide of N. meningitidis serogroup B comprised of a homopolymer of negatively charged sialic acid. There was slightly less binding observed with N. meningitidis serogroup W, which contains repeating units of the neutral sugar galactose and sialic acid. Our work represents the first assessment of the metal-binding properties of these capsular polysaccharides. Future work will seek to optimize metal-binding with Neisseria meningitidis serogroup W polysaccharide. Full article
Figures

Figure 1

Open AccessMeeting Report 11th IUBMB Focused Meeting on the Aminoacyl-tRNA Synthetases: Sailing a New Sea of Complex Functions in Human Biology and Disease
Biomolecules 2018, 8(2), 22; https://doi.org/10.3390/biom8020022
Received: 5 April 2018 / Revised: 25 April 2018 / Accepted: 26 April 2018 / Published: 1 May 2018
Viewed by 1747 | PDF Full-text (1369 KB) | HTML Full-text | XML Full-text
Abstract
The 11th IUBMB Focused Meeting on Aminoacyl-tRNA Synthetases was held in Clearwater Beach, Florida from 29 October–2 November 2017, with the aim of presenting the latest research on these enzymes and promoting interchange among aminoacyl-tRNA synthetase (ARS) researchers. Topics covered in the meeting
[...] Read more.
The 11th IUBMB Focused Meeting on Aminoacyl-tRNA Synthetases was held in Clearwater Beach, Florida from 29 October–2 November 2017, with the aim of presenting the latest research on these enzymes and promoting interchange among aminoacyl-tRNA synthetase (ARS) researchers. Topics covered in the meeting included many areas of investigation, including ARS evolution, mechanism, editing functions, biology in prokaryotic and eukaryotic cells and their organelles, their roles in human diseases, and their application to problems in emerging areas of synthetic biology. In this report, we provide a summary of the major themes of the meeting, citing contributions from the oral presentations in the meeting. Full article
Figures

Figure 1

Open AccessReview Circulating MicroRNA Biomarkers in Melanoma: Tools and Challenges in Personalised Medicine
Biomolecules 2018, 8(2), 21; https://doi.org/10.3390/biom8020021
Received: 9 March 2018 / Revised: 20 April 2018 / Accepted: 23 April 2018 / Published: 26 April 2018
Viewed by 1785 | PDF Full-text (1082 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Effective management of melanoma depends heavily on early diagnosis. When detected in early non-metastatic stages, melanoma is almost 100% curable by surgical resection, however when detected in late metastatic stages III and IV, 5-year survival rates drop to ~50% and 10–25%, respectively, due
[...] Read more.
Effective management of melanoma depends heavily on early diagnosis. When detected in early non-metastatic stages, melanoma is almost 100% curable by surgical resection, however when detected in late metastatic stages III and IV, 5-year survival rates drop to ~50% and 10–25%, respectively, due to limited efficacy of current treatment options. This presents a pressing need to identify biomarkers that can detect patients at high risk of recurrence and progression to metastatic disease, which will allow for early intervention and survival benefit. Accumulating evidence over the past few decades has highlighted the potential use of circulating molecular biomarkers for melanoma diagnosis and prognosis, including lactate dehydrogenase (LDH), S100 calcium-binding protein B (S100B) and circulating tumor DNA (ctDNA) fragments. Since 2010, circulating microRNAs (miRNAs) have been increasingly recognised as more robust non-invasive biomarkers for melanoma due to their structural stability under the harsh conditions of the blood and different conditions of sample processing and isolation. Several pre-analytical and analytical variables challenge the accurate quantification of relative miRNA levels between serum samples or plasma samples, leading to conflicting findings between studies on circulating miRNA biomarkers for melanoma. In this review, we provide a critical summary of the circulating miRNA biomarkers for melanoma published to date. Full article
Figures

Figure 1

Open AccessReview Protein–Phospholipid Interaction Motifs: A Focus on Phosphatidic Acid
Biomolecules 2018, 8(2), 20; https://doi.org/10.3390/biom8020020
Received: 28 February 2018 / Revised: 16 April 2018 / Accepted: 16 April 2018 / Published: 23 April 2018
Cited by 3 | Viewed by 1391 | PDF Full-text (804 KB) | HTML Full-text | XML Full-text
Abstract
Cellular membranes are composed of thousands of different lipids usually maintained within a narrow range of concentrations. In addition to their well-known structural and metabolic roles, signaling functions for many lipids have also emerged over the last two decades. The latter largely depend
[...] Read more.
Cellular membranes are composed of thousands of different lipids usually maintained within a narrow range of concentrations. In addition to their well-known structural and metabolic roles, signaling functions for many lipids have also emerged over the last two decades. The latter largely depend on the ability of particular classes of lipids to interact specifically with a great variety of proteins and to regulate their localization and activity. Among these lipids, phosphatidic acid (PA) plays a unique role in a large repertoire of cellular activities, most likely in relation to its unique biophysical properties. However, until recently, only incomplete information was available to model the interaction between PA and its protein partners. The development of new liposome-based assays as well as molecular dynamic simulation are now providing novel information. We will review the different factors that have shown to modulate the capacity of PA to interact with specific domains in target proteins. Full article
(This article belongs to the Special Issue Cellular Membrane Domains and Organization)
Figures

Graphical abstract

Open AccessFeature PaperArticle Improving the Activity of Trp-Rich Antimicrobial Peptides by Arg/Lys Substitutions and Changing the Length of Cationic Residues
Biomolecules 2018, 8(2), 19; https://doi.org/10.3390/biom8020019
Received: 10 March 2018 / Revised: 14 April 2018 / Accepted: 17 April 2018 / Published: 19 April 2018
Cited by 3 | Viewed by 1846 | PDF Full-text (3781 KB) | HTML Full-text | XML Full-text
Abstract
Antimicrobial peptides (AMPs) constitute a promising alternative for the development of new antibiotics that could potentially counteract the growing number of antibiotic-resistant bacteria. However, the AMP structure–function relationships remain unclear and detailed studies are still necessary. The positively charged amino acid residues (Arg
[...] Read more.
Antimicrobial peptides (AMPs) constitute a promising alternative for the development of new antibiotics that could potentially counteract the growing number of antibiotic-resistant bacteria. However, the AMP structure–function relationships remain unclear and detailed studies are still necessary. The positively charged amino acid residues (Arg and Lys) play a crucial role in the activity of most AMPs due to the promotion of electrostatic interactions between the peptides and bacterial membranes. In this work we have analyzed the antimicrobial and structural properties of several Trp-rich AMPs containing exclusively either Arg or Lys as the positively charged residues. Their antimicrobial activity and mechanism of action were investigated, showing that Lys residues give rise to a reduced antimicrobial potency for most peptides, which was correlated, in turn, with a decrease in their ability to permeabilize the cytoplasmic membrane of Escherichia coli. Additionally, the presence of Arg and Lys renders the peptides susceptible to degradation by proteases, such as trypsin, limiting their therapeutic use. Therefore, modifications of the side chain length of Arg and Lys were investigated in an attempt to improve the protease resistance of AMPs. This approach resulted in enhanced stability to trypsin digestion, and in several cases, shorter sidechains conserved or even improved the antimicrobial activity. All together, these results suggest that Arg-to-Lys substitutions, coupled with side chain length modifications, can be extremely useful for improving the activity and stability of AMPs. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Development, Conjugation, and Beyond)
Figures

Figure 1

Open AccessReview Biophysical Investigations Elucidating the Mechanisms of Action of Antimicrobial Peptides and Their Synergism
Biomolecules 2018, 8(2), 18; https://doi.org/10.3390/biom8020018
Received: 29 March 2018 / Revised: 13 April 2018 / Accepted: 16 April 2018 / Published: 18 April 2018
Cited by 7 | Viewed by 1670 | PDF Full-text (1084 KB) | HTML Full-text | XML Full-text
Abstract
Biophysical and structural investigations are presented with a focus on the membrane lipid interactions of cationic linear antibiotic peptides such as magainin, PGLa, LL37, and melittin. Observations made with these peptides are distinct as seen from data obtained with the hydrophobic peptide alamethicin.
[...] Read more.
Biophysical and structural investigations are presented with a focus on the membrane lipid interactions of cationic linear antibiotic peptides such as magainin, PGLa, LL37, and melittin. Observations made with these peptides are distinct as seen from data obtained with the hydrophobic peptide alamethicin. The cationic amphipathic peptides predominantly adopt membrane alignments parallel to the bilayer surface; thus the distribution of polar and non-polar side chains of the amphipathic helices mirror the environmental changes at the membrane interface. Such a membrane partitioning of an amphipathic helix has been shown to cause considerable disruptions in the lipid packing arrangements, transient openings at low peptide concentration, and membrane disintegration at higher peptide-to-lipid ratios. The manifold supramolecular arrangements adopted by lipids and peptides are represented by the ‘soft membranes adapt and respond, also transiently’ (SMART) model. Whereas molecular dynamics simulations provide atomistic views on lipid membranes in the presence of antimicrobial peptides, the biophysical investigations reveal interesting details on a molecular and supramolecular level, and recent microscopic imaging experiments delineate interesting sequences of events when bacterial cells are exposed to such peptides. Finally, biophysical studies that aim to reveal the mechanisms of synergistic interactions of magainin 2 and PGLa are presented, including unpublished isothermal titration calorimetry (ITC), circular dichroism (CD) and dynamic light scattering (DLS) measurements that suggest that the peptides are involved in liposome agglutination by mediating intermembrane interactions. A number of structural events are presented in schematic models that relate to the antimicrobial and synergistic mechanism of amphipathic peptides when they are aligned parallel to the membrane surface. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Development, Conjugation, and Beyond)
Figures

Figure 1

Open AccessArticle Association between Resistin Gene Polymorphisms and Atopic Dermatitis
Biomolecules 2018, 8(2), 17; https://doi.org/10.3390/biom8020017
Received: 17 February 2018 / Revised: 22 March 2018 / Accepted: 23 March 2018 / Published: 27 March 2018
Viewed by 972 | PDF Full-text (320 KB) | HTML Full-text | XML Full-text
Abstract
Atopic dermatitis (AD) is a chronic, relapsing, and inflammatory skin disorder. It is characterized by an inappropriate skin barrier function, allergen sensitization, and recurrent skin infections. Resistin is an adipokine expressed mainly in macrophages and monocytes; it has a role in the inflammatory
[...] Read more.
Atopic dermatitis (AD) is a chronic, relapsing, and inflammatory skin disorder. It is characterized by an inappropriate skin barrier function, allergen sensitization, and recurrent skin infections. Resistin is an adipokine expressed mainly in macrophages and monocytes; it has a role in the inflammatory process and is associated with multiple inflammatory human diseases; however, only few studies linked resistin to atopic dermatitis. This study tested the association between G>A (rs3745367) and C>T (rs3219177) single nucleotide polymorphisms (SNPs) of the RETN gene with atopic dermatitis. In addition, it explored the relationship between serum resistin protein and atopic dermatitis. To achieve objectives of this study, 162 atopic dermatitis patients and 161 healthy participants were recruited in the study. A significant association was detected between rs3745367 and atopic dermatitis with age and gender specificity (p < 0.05), while no significant association between rs3219177 and atopic dermatitis was found (p > 0.05). For the serum resistin levels, a significant decrease was indicated in atopic dermatitis patients compared to healthy subjects (p < 0.05). In conclusion, rs3745367 may play a gender and age-specific role in atopic dermatitis. In addition, the significant decrease in the resistin protein level confirmed this association. Full article
Figures

Figure 1

Open AccessMeeting Report Role of Nutrition in Alcoholic Liver Disease: Summary of the Symposium at the ESBRA 2017 Congress
Biomolecules 2018, 8(2), 16; https://doi.org/10.3390/biom8020016
Received: 16 March 2018 / Revised: 20 March 2018 / Accepted: 20 March 2018 / Published: 26 March 2018
Viewed by 1266 | PDF Full-text (2785 KB) | HTML Full-text | XML Full-text
Abstract
The symposium, “Role of Nutrition in Alcoholic Liver Disease”, was held at the European Society for Biomedical Research on Alcoholism Congress on 9 October 2017 in Crete, Greece. The goal of the symposium was to highlight recent advances and developments in the field
[...] Read more.
The symposium, “Role of Nutrition in Alcoholic Liver Disease”, was held at the European Society for Biomedical Research on Alcoholism Congress on 9 October 2017 in Crete, Greece. The goal of the symposium was to highlight recent advances and developments in the field of alcohol and nutrition. The symposium was focused on experimental and clinical aspects in relation to the role of different types of dietary nutrients and malnutrition in the pathogenesis of alcoholic liver disease (ALD). The following is a summary of key research presented at this session. The speakers discussed the role of dietary fats and carbohydrates in the development and progression of alcohol-induced multi-organ pathology in animal models of ALD, analyzed novel nutrition-related therapeutics (specifically, betaine and zinc) in the treatment of ALD, and addressed clinical relevance of malnutrition and nutrition support in ALD. This summary of the symposium will benefit junior and senior faculty currently investigating alcohol-induced organ pathology as well as undergraduate, graduate, and post-graduate students and fellows. Full article
(This article belongs to the collection Multi-Organ Alcohol-Related Damage: Mechanisms and Treatment)
Figures

Figure 1

Open AccessArticle An Arabidopsis Clathrin Assembly Protein with a Predicted Role in Plant Defense Can Function as an Adenylate Cyclase
Biomolecules 2018, 8(2), 15; https://doi.org/10.3390/biom8020015
Received: 18 December 2017 / Revised: 15 March 2018 / Accepted: 16 March 2018 / Published: 23 March 2018
Cited by 2 | Viewed by 1412 | PDF Full-text (15625 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Adenylate cyclases (ACs), much like guanylate cyclases (GCs), are increasingly recognized as essential parts of many plant processes including biotic and abiotic stress responses. In order to identify novel ACs, we have applied a search motif derived from experimentally tested GCs and identified
[...] Read more.
Adenylate cyclases (ACs), much like guanylate cyclases (GCs), are increasingly recognized as essential parts of many plant processes including biotic and abiotic stress responses. In order to identify novel ACs, we have applied a search motif derived from experimentally tested GCs and identified a number of Arabidopsis thaliana candidates including a clathrin assembly protein (AT1G68110; AtClAP). AtClAP contains a catalytic centre that can complement the AC-deficient mutant cyaA in E. coli, and a recombinant AtClAP fragment (AtClAP261–379) can produce cyclic adenosine 3′,5′ monophosphate (cAMP) from adenosine triphosphate (ATP) in vitro. Furthermore, an integrated analysis of gene expression and expression correlation implicate cAMP in pathogen defense and in actin cytoskeletal remodeling during endocytic internalization. Full article
Figures

Figure 1

Open AccessReview p53-Mediated Molecular Control of Autophagy in Tumor Cells
Biomolecules 2018, 8(2), 14; https://doi.org/10.3390/biom8020014
Received: 12 February 2018 / Revised: 16 March 2018 / Accepted: 19 March 2018 / Published: 21 March 2018
Cited by 3 | Viewed by 2023 | PDF Full-text (932 KB) | HTML Full-text | XML Full-text
Abstract
Autophagy is an indispensable mechanism of the eukaryotic cell, facilitating the removal and renewal of cellular components and thereby balancing the cell’s energy consumption and homeostasis. Deregulation of autophagy is now regarded as one of the characteristic key features contributing to the development
[...] Read more.
Autophagy is an indispensable mechanism of the eukaryotic cell, facilitating the removal and renewal of cellular components and thereby balancing the cell’s energy consumption and homeostasis. Deregulation of autophagy is now regarded as one of the characteristic key features contributing to the development of tumors. In recent years, the suppression of autophagy in combination with chemotherapeutic treatment has been approached as a novel therapy in cancer treatment. However, depending on the type of cancer and context, interference with the autophagic machinery can either promote or disrupt tumorigenesis. Therefore, disclosure of the major signaling pathways that regulate autophagy and control tumorigenesis is crucial. To date, several tumor suppressor proteins and oncogenes have emerged as eminent regulators of autophagy whose depletion or mutation favor tumor formation. The mammalian cell “janitor” p53 belongs to one of these tumor suppressors that are most commonly mutated in human tumors. Experimental evidence over the last decade convincingly reports that p53 can act as either an activator or an inhibitor of autophagy depending on its subcellular localization and its mode of action. This finding gains particular significance as p53 deficiency or mutant variants of p53 that accumulate in the cytoplasm of tumor cells enable activation of autophagy. Accordingly, we recently identified p53 as a molecular hub that regulates autophagy and apoptosis in histone deacetylase inhibitor-treated uterine sarcoma cells. In light of this novel experimental evidence, in this review, we focus on p53 signaling as a mediator of the autophagic pathway in tumor cells. Full article
(This article belongs to the Special Issue p53 Pathway in Cancer Progression and Cancer Therapy)
Figures

Graphical abstract

Back to Top