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Search Results (598)

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Keywords = acidic and basic amino acids

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26 pages, 4818 KiB  
Article
Novel Anion-Exchange Resins for the Effective Recovery of Re(VII) from Simulated By-Products of Cu-Mo Ore Processing
by Piotr Cyganowski, Pawel Pohl, Szymon Pawlik and Dorota Jermakowicz-Bartkowiak
Int. J. Mol. Sci. 2025, 26(15), 7563; https://doi.org/10.3390/ijms26157563 - 5 Aug 2025
Abstract
The efficient recovery of rhenium (Re), a critical metal in high-tech industries, is essential to address its growing demand and reduce reliance on primary mining. In this study, we developed novel anion-exchange resins for the selective adsorption and recovery of Re(VII) ions from [...] Read more.
The efficient recovery of rhenium (Re), a critical metal in high-tech industries, is essential to address its growing demand and reduce reliance on primary mining. In this study, we developed novel anion-exchange resins for the selective adsorption and recovery of Re(VII) ions from acidic solutions, simulating industrial by-products. The resins were synthesized from a vinylbenzyl chloride-co-divinylbenzene copolymer modified with aliphatic, heterocyclic, and aromatic weakly basic amines, selected from among bis(3-aminopropyl)amine (BAPA), 1-(2-pyrimidinyl)piperazine (PIP), thiosemicarbazide (TSC), 2-amino-3-hydroxypyridine (AHP), 1-(2-hydroxyethyl)piperazine (HEP), 4-amino-2,6-dihydroxypyrimidine (AHPI), and 2-thiazolamine (TA). The adsorption of Re on BAPA, PIP, and HEP resins obeyed the Langmuir model, and the resins exhibited high adsorption capacities, with maximum values reaching 435.4 mg Re g−1 at pH 6. Furthermore, strong selectivity for ReO4 ions over competing species, including Mo, Cu, and V, was noted in solutions simulating the leachates of the by-products of Cu-Mo ores. Additionally, complete elution of Re was possible. The developed resins turned out to be highly suitable for the continuous-flow-mode adsorption of ReO4, revealing outstanding adsorption capacities before reaching column breakthrough. In this context, the novel anion-exchange resins developed offer a reference for further Re recovery strategies. Full article
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20 pages, 4234 KiB  
Article
Study on the Flocculation Characteristics of Protein in Modified Chitosan Membrane and Mung Bean Vermicelli Wastewater
by Zhisheng Liu, Guang Li, Xiaoyu Zhang, Wenjing Li, Tianyi Yang, Zhijie Wang, Jinlong Zuo and Yuyang Wang
Coatings 2025, 15(7), 831; https://doi.org/10.3390/coatings15070831 - 16 Jul 2025
Viewed by 308
Abstract
This study addresses the challenge of chitosan (CS) being difficult to dissolve in water due to its highly ordered crystalline structure. Chitosan is modified with chloroacetic acid to reduce its crystallinity and enhance its water solubility. Through single-factor experiments, the optimal conditions for [...] Read more.
This study addresses the challenge of chitosan (CS) being difficult to dissolve in water due to its highly ordered crystalline structure. Chitosan is modified with chloroacetic acid to reduce its crystallinity and enhance its water solubility. Through single-factor experiments, the optimal conditions for preparing carboxymethyl chitosan film (CMCS) were determined: under conditions of 50 °C, a cellulose substrate (CS) concentration of 18.75 g/L, a NaOH concentration of 112.5 g/L, and a chloroacetic acid concentration of 18.75 g/L, the reaction proceeded for 5 h. Under these conditions, the resulting carboxymethyl chitosan film exhibited the best flocculation effect, forming chitosan films in water that had flocculation activity toward mung bean starch protein wastewater. The successful introduction of carboxyl groups at the N and O positions of the chitosan molecular chain, which reduced the crystallinity of chitosan and enhanced its water solubility, was confirmed through analysis using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The prepared carboxymethyl chitosan film (CMCS) was applied in the flocculation recovery of protein. Through single-factor and response surface experiments, the optimal process conditions for flocculating and recovering protein with CMCS were determined: a CMCS dosage of 1.1 g/L, a reaction time of 39.6 min, a reaction temperature of 42.7 °C, and a pH of 5.2. Under these conditions, the protein recovery rate reached 56.97%. The composition and amino acid profile of the flocculated product were analyzed, revealing that the mung bean protein flocculated product contained 62.33% crude protein. The total essential amino acids (EAAs) accounted for 52.91%, non-essential amino acids (NEAAs) for 47.09%, hydrophobic amino acids for 39.56%, and hydrophilic amino acids for 12.67%. The ratio of aromatic to branched-chain amino acids was 0.31, and the ratio of basic to acidic amino acids was 1.68. These findings indicate that the recovered product has high surface activity and good protein stability, foaming ability, and emulsifying properties. Full article
(This article belongs to the Section Environmental Aspects in Colloid and Interface Science)
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18 pages, 11789 KiB  
Article
Effects of 1-N-Naphthylphthalamic Acid on Root and Leaf Development of Muscari armeniacum and the Related Metabolic and Physiological Features
by Agnieszka Marasek-Ciołakowska, Aleksandra Machlańska, Wiesław Wiczkowski, Dorota Szawara-Nowak, Lesław B. Lahuta, Justyna Góraj-Koniarska, Kensuke Miyamoto, Junichi Ueda, Marian Saniewski and Marcin Horbowicz
Int. J. Mol. Sci. 2025, 26(13), 6431; https://doi.org/10.3390/ijms26136431 - 3 Jul 2025
Viewed by 362
Abstract
The effects of 1-N-naphthylphthalamic acid (NPA) applied as an aqueous solution on uncooled grape hyacinth (Muscari armeniacum) bulbs were investigated, focusing on histological measurements and the determination of various metabolites in developing roots. M. armeniacum bulbs were kept for [...] Read more.
The effects of 1-N-naphthylphthalamic acid (NPA) applied as an aqueous solution on uncooled grape hyacinth (Muscari armeniacum) bulbs were investigated, focusing on histological measurements and the determination of various metabolites in developing roots. M. armeniacum bulbs were kept for a defined number of days in distilled water (control) or aqueous NPA solutions, and then 2 cm sections of root tips were taken for histological measurements. Longitudinal and cross sections were taken in these root pieces, followed by measurements of their basic parts and microscopic images. Determinations of polar compounds by GC/MS and phenolic metabolites by HPLC/MS/MS were carried out in freeze-dried root samples. NPA inhibited the growth of the roots and caused swelling of their elongation parts, as well as changes in the dimensions of other parts of the roots and disruption of the gravitropic direction of their growth. However, NPA did not affect leaf growth and the amino acid, organic acid, and major carbohydrate content in the roots, but increased the level of unknown saccharides, probably oligofructans. The decrease in the contents of many phenolic compounds observed in our study under the influence of NPA may indicate that this could be one of the symptoms/causes of root growth disorders. In turn, the reduction in polyphenol levels may have been related to an increase in the number and length of root hairs. Full article
(This article belongs to the Section Molecular Plant Sciences)
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34 pages, 1227 KiB  
Review
Understanding Renal Tubular Function: Key Mechanisms, Clinical Relevance, and Comprehensive Urine Assessment
by Mario Alamilla-Sanchez, Miguel Angel Alcalá Salgado, Victor Manuel Ulloa Galván, Valeria Yanez Salguero, Martín Benjamin Yamá Estrella, Enrique Fleuvier Morales López, Nicte Alaide Ramos García, Martín Omar Carbajal Zárate, Jorge David Salazar Hurtado, Daniel Alberto Delgado Pineda, Leticia López González and Julio Manuel Flores Garnica
Pathophysiology 2025, 32(3), 33; https://doi.org/10.3390/pathophysiology32030033 - 3 Jul 2025
Viewed by 1903
Abstract
Renal function refers to the combined actions of the glomerulus and tubular system to achieve homeostasis in bodily fluids. While the glomerulus is essential in the first step of urine formation through a coordinated filtration mechanism, the tubular system carries out active mechanisms [...] Read more.
Renal function refers to the combined actions of the glomerulus and tubular system to achieve homeostasis in bodily fluids. While the glomerulus is essential in the first step of urine formation through a coordinated filtration mechanism, the tubular system carries out active mechanisms of secretion and reabsorption of solutes and proteins using specific transporters in the epithelial cells. The assessment of renal function usually focuses on glomerular function, so the tubular function is often underestimated as a fundamental part of daily clinical practice. Therefore, it is essential to properly understand the tubular physiological mechanisms and their clinical association with prevalent human pathologies. This review discusses the primary solutes handled by the kidneys, including glucose, amino acids, sodium, potassium, calcium, phosphate, citrate, magnesium and uric acid. Additionally, it emphasizes the significance of physicochemical characteristics of urine, such as pH and osmolarity. The use of a concise methodology for the comprehensive assessment of urine should be strengthened in the basic training of nephrologists when dealing with problems such as water and electrolyte balance disorders, acid-base disorders, and harmful effects of commonly used drugs such as chemotherapy, antibiotics, or diuretics to avoid isolated replacement of the solute without carrying out comprehensive approaches, which can lead to potentially severe complications. Full article
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65 pages, 1590 KiB  
Review
Glucosinolate Metabolites and Brain Health: An Updated Review on Their Potential Benefits in Neurodegenerative, Neurodevelopmental, and Psychiatric Disorders
by Claudia Muscarà, Agnese Gugliandolo, Emanuela Mazzon and Gabriella Calì
Antioxidants 2025, 14(7), 818; https://doi.org/10.3390/antiox14070818 - 2 Jul 2025
Viewed by 570
Abstract
Neurodegenerative, neurodevelopmental, and psychiatric disorders, as well as epilepsy, affect millions of people. Due to their impact on patients’ quality of life, they represent a major health issue. Natural compounds are arising as new treatments for these diseases. Particularly, glucosinolates (GLS) are secondary [...] Read more.
Neurodegenerative, neurodevelopmental, and psychiatric disorders, as well as epilepsy, affect millions of people. Due to their impact on patients’ quality of life, they represent a major health issue. Natural compounds are arising as new treatments for these diseases. Particularly, glucosinolates (GLS) are secondary metabolites found in Cruciferae family plants. Their basic structure consists of a glucose unit linked to a thiohydroximate-O-sulfonate group and an aliphatic, aralkyl, or indolyl side chain, depending on their precursor amino acid. Specifically, aliphatic GLS derive from methionine, aromatic ones from phenylalanine, and indolic ones from tryptophan. Myrosinase (thioglucoside glucohydrolase) is the crucial enzyme for GLS degradation, leading to the production of isothiocyanates (ITCs). ITCs attracted considerable scientific interest for their protective effects against various diseases, thanks to their antioxidant, anti-inflammatory, and neuroprotective properties. Here, we collected the latest evidence regarding ITC effects in neurodegenerative, neurodevelopmental, and psychiatric disorders, including preclinical and clinical studies published in the last decade. These studies evidenced ITCs’ neuroprotective effects, exerted mainly through antioxidant and anti-inflammatory mechanisms. Thus, ITCs’ integration, also through the diet, may represent a safe and efficacious strategy to improve health and limit the risk of neurological and psychiatric disorders. However, new large-scale trials are needed to determine their therapeutic potential, particularly for diseases with no clinical evidence. Full article
(This article belongs to the Special Issue Role of Natural Antioxidants on Neuroprotection)
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26 pages, 889 KiB  
Review
Cutting-Edge Approaches in the Co-Amorphization Process
by Azza A. K. Mahmoud, Géza Regdon and Katalin Kristó
Pharmaceutics 2025, 17(7), 850; https://doi.org/10.3390/pharmaceutics17070850 - 29 Jun 2025
Viewed by 526
Abstract
Background: Recently, the co-amorphization method has been widely used to refine the bioavailability characteristics of poorly soluble drugs in addition to overcoming the drawbacks of other traditional amorphization techniques. Objectives: The main aim of this systematic review is to present an extensive outline [...] Read more.
Background: Recently, the co-amorphization method has been widely used to refine the bioavailability characteristics of poorly soluble drugs in addition to overcoming the drawbacks of other traditional amorphization techniques. Objectives: The main aim of this systematic review is to present an extensive outline of different co-former classes, co-former selection, and evaluation of produced co-amorphous systems. Methods: The systematic research was carried out based on three different databases, including PubMed, Scopus, and Web of Science time using co-amorphous, co-former, and drug as keywords. The selected papers were written in the English language and published between 2016 and 2024, and they focused on the co-amorphous systems, while articles discussing other amorphization techniques and crystallization processes were excluded. Results: 127 peer-reviewed articles were selected and summarized. Conclusions: This paper revealed that amino acid is the most commonly used co-former, specifically arginine with acidic drugs and tryptophan with acidic and basic drugs, and it reported other co-formers that were used and different co-amorphous systems with their dissolution behaviour and stabilities, and different computational tools that were applied in the selection of co-former and process result evaluation. Full article
(This article belongs to the Special Issue Advances in Analysis and Modeling of Solid Drug Product)
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29 pages, 3563 KiB  
Article
Amino Acid Polymorphisms in the Basic Region of Meq of Vaccine Strain CVI988 Drastically Diminish the Virulence of Marek’s Disease Virus
by Jumpei Sato, Yoshinosuke Motai, Shunsuke Yamagami, Aoi Kurokawa, Shwe Yee Win, Fumiya Horio, Hikaru Saeki, Naoya Maekawa, Tomohiro Okagawa, Satoru Konnai, Kazuhiko Ohashi and Shiro Murata
Viruses 2025, 17(7), 907; https://doi.org/10.3390/v17070907 - 26 Jun 2025
Viewed by 292
Abstract
Marek’s disease virus (MDV) is the etiological agent of Marek’s disease (MD), a lymphoproliferative disorder in chickens. Polymorphisms in the MDV-encoded oncoprotein Meq are shared among field strains and correlate with their virulence. The attenuated vaccine strain CVI988 harbors unique amino acid polymorphisms [...] Read more.
Marek’s disease virus (MDV) is the etiological agent of Marek’s disease (MD), a lymphoproliferative disorder in chickens. Polymorphisms in the MDV-encoded oncoprotein Meq are shared among field strains and correlate with their virulence. The attenuated vaccine strain CVI988 harbors unique amino acid polymorphisms in Meq, particularly at positions 71, 77, and 326. In this study, we investigated the impact of these polymorphisms on Meq protein function and MDV virulence. Reporter assays revealed that the substitutions, particularly A71S and K77E, markedly impaired the transcriptional regulatory activity of Meq. To evaluate their effect on virulence, we generated a recombinant MDV based on the very virulent RB-1B strain, encoding Meq with A71S and K77E substitutions (rRB-1B_Meq71/77). Chickens infected with rRB-1B_Meq71/77 developed neither clinical signs nor lymphomas. Flow cytometry revealed no expansion of infected cells in this group, but a marked increase in CD8+ T and γδ T cells during early infection. Histopathological analysis also confirmed the absence of MD-associated lesions. These findings demonstrate that the polymorphisms at positions 71 and 77 in the CVI988 strain are sufficient to abolish MDV virulence. This study provides insight into the molecular basis of MDV virulence and informs the strategy for the design of more effective vaccines. Full article
(This article belongs to the Section Animal Viruses)
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19 pages, 4323 KiB  
Article
A Halophilic Bacterium for Bioremediation of Saline–Alkali Land: The Triadic and Synergetic Response Mechanism of Oceanobacillus picturae DY09 to Salt Stress
by Tianying Nie, Liuqing Wang, Yilan Liu, Siqi Fu, Jiahui Wang, Kunpeng Cui and Lu Wang
Microorganisms 2025, 13(7), 1474; https://doi.org/10.3390/microorganisms13071474 - 25 Jun 2025
Cited by 1 | Viewed by 499
Abstract
The strain of Oceanobacillus picturae DY09, as a typical halophilic microorganism, possesses distinctive salt adaptation mechanisms that hold significant application value in the fields of agriculture, industry, and biomedicine. To deeply analyze the salt-tolerance molecular mechanism of this strain, this research disclosed its [...] Read more.
The strain of Oceanobacillus picturae DY09, as a typical halophilic microorganism, possesses distinctive salt adaptation mechanisms that hold significant application value in the fields of agriculture, industry, and biomedicine. To deeply analyze the salt-tolerance molecular mechanism of this strain, this research disclosed its salt-tolerance strategies under diverse salt concentrations through transcriptomics. In a low-salt environment, the DY09 strain adopted a “metabolic simplification” strategy, significantly reducing the metabolic load by promoting lysine degradation and inhibiting the biosynthesis of branched-chain amino acids and glycine betaine (GB) but upregulating the expression of the GB transporter gene betH and preferentially utilizing exogenous GB to maintain basic osmotic balance. When exposed to high-salt stress, this strain activated multiple regulatory mechanisms: it upregulated the expression of Na+/K+ antiporter proteins to maintain ionic homeostasis; the synthesis genes of amino acids such as arginine and proline were significantly upregulated, and the GB synthesis genes betA/B and the transporter gene betH were upregulated concurrently, which realized the synergistic operation of endogenous synthesis and exogenous uptake of osmoprotective substances. The expression level of the antioxidant enzyme systems is upregulated to scavenge reactive oxygen species. Simultaneously, the molecular chaperones groES/groEL and GB cooperate to maintain the functional stability of the protein. In this study, a trinity salt-tolerance-integrated strategy of “dynamic perception–hierarchical response–system synergy” of halophilic bacteria was initially proposed, which provided a research idea for exploring the salt–alkali-tolerant mechanism of halophilic bacteria and a theoretical basis for the further development and application of this strain. Full article
(This article belongs to the Section Molecular Microbiology and Immunology)
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23 pages, 3772 KiB  
Article
Integrated Microbiome and Metabolomics Insights into Meat Quality Changes in Rice-Field Eel Slices During Refrigeration Storage: Effects of ε-Polylysine, Vitamin C, Epigallocatechin Gallate, and Phloretin
by Liu Shi, Lifeng Yang, Juan You, Wenjin Wu, Guangquan Xiong, Lan Wang and Tao Yin
Foods 2025, 14(13), 2236; https://doi.org/10.3390/foods14132236 - 25 Jun 2025
Viewed by 477
Abstract
Rice-field eel (Monopterus albus) slices, an important aquatic product in Southeast Asia, are prone to spoilage and deterioration during cold chain storage. In this study, the effects of a composite preservative (ε-polylysine, Vitamin C (Vc), epigallocatechin gallate (EGCG), and phloretin) on [...] Read more.
Rice-field eel (Monopterus albus) slices, an important aquatic product in Southeast Asia, are prone to spoilage and deterioration during cold chain storage. In this study, the effects of a composite preservative (ε-polylysine, Vitamin C (Vc), epigallocatechin gallate (EGCG), and phloretin) on the muscle quality (color, texture, water holding capacity (WHC)) of rice-field eel slices during refrigeration storage at 4 °C for up to 7 days was investigated, and the underlying mechanism was elucidated by the integrated microbiome and metabolomics, in addition to Elisa and Low-Field Nuclear Magnetic Resonance (LF-NMR). After 7 days of storage, the WHC, shear force, and a* decreased by 11.39%, 34.37%, and 49.20% in treated samples, and by 19.18%, 38.38%, and 54.87% in control samples, respectively. The addition of the composite preservative significantly increased Hexokinase, Pyruvate kinase, and Creatine kinase, while it decreased the total viable count (TVC), total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substance (TBARS), and Lactic acid. Preservative treatment maintained the moisture content of the eel slices during storage and prevented bright red oxymyoglobin from transforming into brown metmyoglobin. Microbiota composition (especially Pseudomonas) and metabolic pathways (including amino acid and its metabolites, nucleotide and its metabolite, and organic acid and its derivatives, etc.) were obviously altered by the preservative treatment. Pseudomonas, tryptophan-aspartic acid (Trp-Asp), D-Glucose 6-phosphate, Succinic Acid, Biliverdin 1, 5-Diaminopentane, and Tyramine, etc., are potential biomarkers for the quality changes of eel slices during refrigeration. These findings provide an in-depth understanding of the improvement of the eel slice quality during refrigeration storage by the composite preservative. Full article
(This article belongs to the Section Foods of Marine Origin)
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16 pages, 1076 KiB  
Article
Effects of Dietary Rhodotorula Yeast Culture Supplementation on Physicochemical Properties, Antioxidant Capacity, Shelf Life, and Flavor Substance of the Longissimus dorsi Muscle in Fattening Lambs
by Guang Yang, Meiru Chen, Xinyu Lu, Gaowei Zhang, Ke Wang, Xiangtan Su and Aiqin Gao
Agriculture 2025, 15(12), 1265; https://doi.org/10.3390/agriculture15121265 - 11 Jun 2025
Viewed by 1127
Abstract
This study evaluated the effects of dietary Rhodotorula yeast culture (RYC) supplementation on carcass traits, meat quality, antioxidant capacity, shelf life, and flavor substance in fattening lambs. Twenty-four three-month-old male Dorper × Han crossbred sheep (body weight: 36 ± 4 kg) were randomly [...] Read more.
This study evaluated the effects of dietary Rhodotorula yeast culture (RYC) supplementation on carcass traits, meat quality, antioxidant capacity, shelf life, and flavor substance in fattening lambs. Twenty-four three-month-old male Dorper × Han crossbred sheep (body weight: 36 ± 4 kg) were randomly assigned to four groups: R0 (basal diet), R10 (basal diet + 10 g RYC/day), R20 (basal diet + 20 g RYC/day), and R40 (basal diet + 40 g RYC/day). The experiment lasted 75 days. Compared to the control group, the R10, R20, and R40 groups exhibited significant reductions in shear force (p < 0.01), malondialdehyde levels (p < 0.01), and day-15 total volatile basic nitrogen values (p < 0.05), along with significant increases in glutathione peroxidase activity (p < 0.05) and total umami-taste amino acid content (p < 0.01). The R20 group also demonstrated significant increases in backfat thickness, muscle crude protein content, and total antioxidant capacity (p < 0.05). These results indicate that dietary supplementation with 20 g RYC improves physicochemical properties, antioxidant capacity, shelf life, and flavor compounds in fattening lambs. Full article
(This article belongs to the Section Agricultural Product Quality and Safety)
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17 pages, 1977 KiB  
Article
Biochemical and Functional Characterization of E. coli Aminopeptidase N: A New Role as a 6-Monoacetylmorphine Hydrolase
by Xiabin Chen, Yishuang Li, Jianzhuang Yao, Xiaoxuan Li, Hualing Li, Zelin Wu, Qi Hu, Nuo Xu, Tingjun Hou, Jiye Wang and Shurong Hou
Biomolecules 2025, 15(6), 822; https://doi.org/10.3390/biom15060822 - 5 Jun 2025
Viewed by 550
Abstract
6-monoacetylmorphine (6-MAM), a primary active metabolite of heroin that reaches the human brain, plays a crucial role in producing heroin-associated physiological and lethal effects. Therefore, 6-MAM has emerged as a key target for alleviating the adverse consequences of heroin abuse. In this study, [...] Read more.
6-monoacetylmorphine (6-MAM), a primary active metabolite of heroin that reaches the human brain, plays a crucial role in producing heroin-associated physiological and lethal effects. Therefore, 6-MAM has emerged as a key target for alleviating the adverse consequences of heroin abuse. In this study, the proposed 6-MAM hydrolase E. coli aminopeptidase N (eAPN) was recombinantly produced, and its biochemical and functional profiles were investigated. eAPN’s biochemical properties, with respect to pH, metal ions, and temperature, and catalytic functions toward peptidase substrates and 6-MAM were thoroughly examined. Extensive experiments reveal that incorporation of an N-terminal His-tag notably affects eAPN’s aminopeptidase activity. This cost-effective recombinant eAPN exhibits favorable thermostability and optimal activity at pH 7.5. Kinetic analysis toward peptidase substrates reveals that eAPN preferentially cleaves peptides following amino acid residues in the order of Ala > Arg >> Met, Gly > Leu > Pro, indicating a preference for small or basic amino acid residues as substrates. Computational and experimental studies have, for the first time, discovered that eAPN is capable of catalyzing the hydrolysis of heroin and 6-MAM, which has shed light on its functional versatility and potential applications. This work elucidates the biochemical properties of eAPN and expands its catalytic functions, thereby laying the groundwork for a deep understanding and further reengineering of eAPN to enhance its activity toward 6-MAM for heroin detoxification. Full article
(This article belongs to the Section Enzymology)
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21 pages, 72960 KiB  
Article
Explainability of Protein Deep Learning Models
by Zahra Fazel, Camila P. E. de Souza, G. Brian Golding and Lucian Ilie
Int. J. Mol. Sci. 2025, 26(11), 5255; https://doi.org/10.3390/ijms26115255 - 29 May 2025
Viewed by 618
Abstract
Protein embeddings are the new main source of information about proteins, producing state-of-the-art solutions to many problems, including protein interaction prediction, a fundamental issue in proteomics. Understanding the embeddings and what causes the interactions is very important, as these models lack transparency due [...] Read more.
Protein embeddings are the new main source of information about proteins, producing state-of-the-art solutions to many problems, including protein interaction prediction, a fundamental issue in proteomics. Understanding the embeddings and what causes the interactions is very important, as these models lack transparency due to their black-box nature. In the first study of its kind, we investigate the inner workings of these models using XAI (explainable AI) approaches. We perform extensive testing (3.3 TB of total data) involving nine of the best-known XAI methods on two problems: (i) the prediction of protein interaction sites using the current top method, Seq-InSite, and (ii) the production of protein embedding vectors using three methods, ProtBERT, ProtT5, and Ankh. The results are evaluated in terms of their ability to correlate with six basic amino acid properties—aromaticity, acidity/basicity, hydrophobicity, molecular mass, van der Waals volume, and dipole moment—as well as the propensity for interaction with other proteins, the impact of distant residues, and the infidelity scores of the XAI methods. The results are unexpected. Some XAI methods are much better than others at discovering essential information. Simple methods can be as good as advanced ones. Different protein embedding vectors can capture distinct properties, indicating significant room for improvement in embedding quality. Full article
(This article belongs to the Section Biochemistry)
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25 pages, 5953 KiB  
Article
Evaluation of the Functional Properties and Edible Safety of Concocted Xanthii Fructus Protein
by Yuchen Dong, Zihao Wan, Fuguo Han, Xuemei Fan, Yanli Hao, Fang Wei and Qingfei Liu
Foods 2025, 14(11), 1913; https://doi.org/10.3390/foods14111913 - 28 May 2025
Viewed by 540
Abstract
Xanthii Fructus (XF) not only has medicinal function in traditional Chinese medicine (TCM) but also contains rich oil and protein. The aim of this research was to develop the edible value of its protein based on the investigation on the extraction, basic characteristics [...] Read more.
Xanthii Fructus (XF) not only has medicinal function in traditional Chinese medicine (TCM) but also contains rich oil and protein. The aim of this research was to develop the edible value of its protein based on the investigation on the extraction, basic characteristics and functions, safety, gut microbiota, and metabolomics, especially the effect of the concocting process. The proteins from raw and concocted XF were prepared using two methods: alkaline solubilization followed by acid precipitation and ammonium sulfate salting-out, respectively. The secondary structure and physicochemical properties of the proteins were characterized through spectroscopic analysis and property determination. The effects of alkaline and the concocting process on the proteins were systematically compared. The results indicated that the salting-out method could retain the protein activity better. Both alkali treatment and the concocting process altered the folding state of proteins. The toxicological results in mice indicated that a high dose (0.35 g/kg) of raw Xanthii Fructus protein (XFP) might cause damage to the liver and small intestine, and the concocting process could significantly alleviate the damage. The 16S rRNA sequencing technology was used to untangle their impact on gut microbiota in mice and the result showed that raw protein had a certain regulatory effect on Bifidobacterium, Rhodococcus, Lactococcus, and Clostridium, while the concocted protein had a smaller impact, mainly affecting Bacteroides and Bifidobacterium. The untargeted metabolomics using liquid chromatography-mass spectrometry (LC-MS) showed that the proteins of raw XF affected the metabolic level through cysteine and methionine metabolism, purine metabolism, amino sugar and nucleotide sugar metabolism pathways, and the concocted protein mainly involved histidine metabolism and purine metabolism pathways. Overall, XFP had potential development prospects, but the anti-nutritional factors might have some toxicity. The concocting process could significantly improve its safety, and the concocted proteins were worth developing as a food source. In the future, the processing conditions should be further optimized and more systematic investigation should be performed to ensure the safety of XF as a food source. Full article
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22 pages, 11465 KiB  
Article
The Effect of Different Processing Methods on Metabolite Profiles by Comparative Metabolomics in Kernels and Sprouted Seeds of Foxtail Millet
by Lingda Han, Qi Li and Xiaowen Wang
Foods 2025, 14(11), 1900; https://doi.org/10.3390/foods14111900 - 27 May 2025
Viewed by 452
Abstract
Foxtail millet attracts much attention for its rich nutrients and health benefits. However, ultra-polishing has greatly reduced its nutrition. Germination can enhance nutrition value. Nevertheless, knowledge of nutrient changes in kernels and sprouted grains under different polishing methods and at different germination stages [...] Read more.
Foxtail millet attracts much attention for its rich nutrients and health benefits. However, ultra-polishing has greatly reduced its nutrition. Germination can enhance nutrition value. Nevertheless, knowledge of nutrient changes in kernels and sprouted grains under different polishing methods and at different germination stages is limited. Here, comparative metabolomics was used to detect metabolite changes in differently polished millets (Manually Polished Millet, MPM; Ultra-Polished Millet, UPM; Manually Ultra-Polished Millet, MUPM) and in sprouted grains with hot air drying (HAD) and freeze-drying (FD) at different germination times. Compared to whole grains, MPM, UPM, and MUPM had 306 to 720 down-regulated metabolites, reducing most antioxidants, essential amino acids, fatty acids, and vitamins in whole grains. For sprouted grains, metabolic activities were comprehensively activated. The early stages accumulated basic nutrients such as free and functional amino acids, small sugars, and essential fatty acids. The 16 h stage increased secondary antioxidant metabolites like flavonoids, and the 24 h germination generated more functional components such as sulfur-containing metabolites. More basic nutrients were preserved by FD in comparison to the reduced basic nutrients and increased antioxidant accumulation associated with HAD. This work systematically characterizes the metabolite changes in polished millets and sprouted grains, providing a reference for developing functional millet products. Full article
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20 pages, 5008 KiB  
Article
Integration of Transcriptomics and Metabolomics Reveals Mechanisms of High-Temperature Stress Tolerance in the Hepatopancreas of Penaeus monodon
by Li Liu, Peng Zhao, Lishi Yang, Yundong Li, Zhong Huang, Qibin Yang, Yukai Yang, Jianzhi Shi, Yibiao Chen and Jianhua Huang
Biology 2025, 14(6), 591; https://doi.org/10.3390/biology14060591 - 23 May 2025
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Abstract
High temperatures in summer often trigger disease outbreaks in shrimp, resulting in significant economic losses. To investigate the heat tolerance mechanisms of Penaeus monodon, juvenile tiger shrimp were subjected to a high-temperature stress of 38 °C for 144 h. The cumulative survival [...] Read more.
High temperatures in summer often trigger disease outbreaks in shrimp, resulting in significant economic losses. To investigate the heat tolerance mechanisms of Penaeus monodon, juvenile tiger shrimp were subjected to a high-temperature stress of 38 °C for 144 h. The cumulative survival rate of shrimp sharply decreased to 5.29% in the later 144 h. The heat-sensitive shrimps (S group) were collected in the first 24 h, while those that survived beyond 120 h were collected as the heat-tolerant group (T group). The hepatopancreas of two groups was subjected to transcriptomic and metabolomic analysis. The results revealed that, compared to the S group, the T group exhibited a total of 3527 DEGs, including 2199 upregulated and 1328 downregulated genes. Additionally, 353 DAMs were identified in the T group, with 75 metabolites showing increased levels and 278 metabolites displaying decreased levels. The results revealed that the mechanisms of heat tolerance involve energy supply strategies, immune system regulation, amino acid metabolism, and glutathione metabolism. Energy supply strategies include the digestion and absorption of carbohydrates and proteins, glycolysis/gluconeogenesis, fructose and mannose metabolism, and pyruvate metabolism, all of which collectively meet energy demands in high-temperature environments. The immune system is regulated by C-type lectin receptor pathways and IL-17 signaling pathways, which together coordinate innate immunity to prevent pathogen invasion. In amino acid metabolism, various glycogenic amino acids, such as histidine, phenylalanine, valine, and serine, are metabolized for energy, while excess ammonia is converted to γ-glutamyl-glutamate and L-glutamate to mitigate ammonia accumulation. Combined transcriptomic and metabolomic analyses further indicate that glutathione metabolism plays a crucial role in the adaptation of P. monodon to high-temperature environments. This study explains the high-temperature tolerance mechanism of P. monodon from the aspects of gene expression regulation and material metabolism regulation and also provides a scientific basis and basic data for the selection and breeding of new varieties of P. monodon with a high-temperature tolerance. Full article
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