Search Results (3,280)

The bactericidal permeability-increasing protein (BPI) and lipopolysaccharide binding protein (LBP) are fundamental to innate immunity. However, their functional diversity and evolutionary conservation in ecologically crucial invertebrates, such as oysters, remain largely understudied. In this study, we identify and characterize a novel homolog of BPI/LBP, designated as ChBPI/LBP in the Hong Kong oyster (Crassostrea hongkongensis). Through structural and phylogenetic analysis, we identify ChBPI/LBP as a distinct member of the BPI protein family, with a high isoelectric point (pI of 9.26), indicating potent cationic BPI-like bactericidal function. We found that ChBPI/LBP is constitutively highly expressed at mucosal sites such as the gills and is rapidly upregulated in hemocytes following a challenge with Aeromonas hydrophila. Recombinant ChBPI/LBP demonstrated potent and specific bactericidal activity against Gram-negative pathogens. These findings suggest that ChBPI/LBP is an important antimicrobial peptide (AMP) effector in the oyster’s immune response. This work provides novel perspectives on the evolutionary mechanisms of innate immunity in bivalves and may have implications for disease management in aquaculture. Full article

Ovarian cancer is a highly lethal disease. Tumors with a deficiency in the homologous recombination repair pathway (HRD) resulting from mutations in BRCA1/2 genes have a favorable response to platinum-based chemotherapy and targeted therapy with PARP inhibitors (PARPi) mediated by synthetic lethality. Promoter methylation of BRCA1/2 genes was previously associated with HRD, but little is known about whether it translates to clinical benefit. Here, we evaluated the prevalence of BRCA1/2 promoter methylation in HGSOC patients from Serbia and examined their clinicopathological characteristics and the effect on progression-free and overall survival. Using methylation-specific PCR, we screened for hypermethylation in the promoter region of BRCA1/2 genes in a cohort of 244 patients. We found fully methylated BRCA1 and BRCA2 promoter in 4.1% and 0.45% of patients, and 23.36% and 11.21% intermediately methylated cases, respectively. Full BRCA1/2 promoter methylation was significantly associated with younger age of onset (55 and 58 years, respectively) compared to BRCA1/2-mutated cases, suggestive of BRCAness phenotype. However, in the exploratory analysis of 68 patients with clinical follow-up, we did not find a strong survival advantage for BRCA1/2 methylated over BRCA1/2-intact cases, yet more moderate effects cannot be ruled out due to the cohort size. Full article

3D printing offers great potential for rapid and cost-effective fabrication of microfluidic lab-on-a-chip systems. Through a comparative approach, we implemented staggered herringbone mixer (SHM), Tesla mixer, and split and recombine mixer (SAR), along with a basic unperturbed channel into one chip and performed comparative mixing efficiency experiments. We also introduced a phaseguide-based, T-shaped stop structure at the Y-shaped inlets for bubble-free and parallel filling. The structures were analyzed with two poorly mixable dye solutions at flow rates ranging from 1 µL/min to 200 µL/min. The mixing efficiency was evaluated using optical gray value analysis and compared against diffusion-based mixing. The fluid-aligning phaseguides in the 3D-printed system were shown to work. Among the three different mixing structures tested, SHM exhibited the best mixing efficiency at all tested flow rates. Uniformly designed SHM structures contain a region of poor mixing between the two zones of turbulence. In a non-uniform design, fluid breakers were placed between two SHM units to redirect poorly mixed fluids to the edges, resulting in 100% mixing efficiency across all measured flow rates. These results, especially SHM with fluid breakers, support the development of cost-effective injection-molded lab-on-a-chip systems with improved mixing functionalities at close range instead of simple long-length meandric systems. Full article

Apple aroma is an important factor influencing consumers’ preferences. To understand the overall flavor characteristics of apples (Ruixue, Liangzhi, Grystal Fuji, and Guifei), volatile compounds and aroma profiles were investigated by headspace–gas chromatography–ion mobility spectrometry (HS-GC-IMS) combined with stir bar sorptive extraction (SBSE) and gas chromatography–mass spectrometry (GC-MS). The results showed that a total of 56 aroma compounds were identified by SBSE-GC-MS, and 39 aroma-active compounds were screened out using aroma intensity (AI) and odor activity value (OAV). Aroma recombination experiments showed enhanced ‘fruity’ and ‘sweet’ notes, whereas ‘floral’, ‘woody’, and ‘green’ aromas were weaker compared to the Crystal Fuji sample. Additionally, GC-IMS coupled with principal component analysis (PCA) was used to distinguish the apple samples, and partial least squares regression (PLSR) was applied to explore the correlation between sensory attributes and characteristic aroma compounds. The results indicated that Crystal Fuji exhibited the greatest correlation with the “woody” attribute, and Ruixue was highly correlated with “fruity”, “green”, and “sour” attributes, while butanoic acid, β-damascenone, butyl acetate, pentyl acetate, furfuryl alcohol, γ-decalactone, and vanillin had a significant impact on the “flower” and “sweet” attributes of Guifei. This study clarified the characteristic aroma composition of the four apple cultivars, providing data support for apple flavor quality evaluation and cultivar optimization. Full article

Enteroviruses (EVs) are small, non-enveloped RNA viruses that can cause diverse clinical outcomes, particularly severe in patients with primary immunodeficiency (PID) due to their impaired ability to clear infections. This study aimed to characterize EV excretion among 138 Tunisian PID patients over a five-year period, to identify circulating EV serotypes and assess their genetic diversity. A total of 558 stool samples were collected and analyzed by virus isolation and intratypic differentiation using RT-qPCR. Molecular typing was performed through Sanger sequencing of the VP1 region and whole genome sequencing using Next-Generation Sequencing (NGS) technologies. Phylogenetic analysis was conducted using the Maximum Likelihood (ML) method. EVs were detected in 55 stool samples from 23 patients. The excretion kinetics of EVs ranged between 30 and 946 days. Thirteen serotypes were identified, including one Poliovirus (PV) and twelve Non-Polio Enteroviruses (NPEVs), predominantly belonging to species B. Two previously unreported serotypes in Tunisia were detected: Coxsackievirus A5 (CVA5) and Echovirus type 19 (E19). In addition, five patients presented enhanced susceptibility to the excretion of successive EV serotypes, and one patient exhibited a co-infection. A possible recombination event was identified in one patient involving Coxsackievirus B5 (CVB5), Coxsackievirus A9 (CVA9) and Coxsackievirus B1 (CVB1) sequences. Phylogenetic analysis showed close genetic relationships with European, American and Asian strains. These findings underscore the dynamic nature of EV circulation and the importance of ongoing molecular surveillance to detect emerging serotypes and guide public health strategies. Full article

A total of 168 fecal samples were obtained from both diarrheic dogs exhibiting clinical symptoms and clinically healthy individuals across four provinces/cities in Northern Vietnam. Based on a polymerase chain reaction method, the Gyrovirus gala 1 (GyVg1) genome was found in 18 (10.71%) of 168 samples. Six representative GyVg1 genomes identified in Vietnam were each 2375 nucleotides long. They shared nucleotide identities of 94.98–98.62%. Whole genome phylogenetic analysis showed that the six obtained GyVg1 strains were grouped into two distinct lineages: GyVg1 I (2/6 strains) and GyVg1 II (4/6 strains). Vietnamese GyVg1 strains were genetically related to Chinese strains. Multiple residue replacements were identified in VP (VP1–VP3) proteins of the Vietnamese GyVg1 strains. A recombination event led to the emergence of the GyVg1/Dog/VNUA-06 recombinant strain. Overall, these observations indicate the presence of GyVg1 viruses in domestic dogs in the North of Vietnam. Full article

Micromixers are crucial for rapid and homogeneous mixing in lab-on-a-chip systems. This study presents a novel passive micromixer that synergistically combines a Zigzag channel with D-shaped obstacles to enhance mixing across a broad Reynolds number (Re) range of 0.1–50. The design leverages flow splitting, recombination, and the generation of localized high-velocity streams to effectively disrupt laminar flow. A comprehensive parametric study optimized key geometric parameters, including obstacle dimensions (b₂, a₂) and the number of mixing units (n). Results show that optimizing b₂ to 500 μm and increasing a₂ to 250 μm significantly enhances mixing efficiency. Mechanistic analysis reveals that centrifugal forces in the Zigzag channel work synergistically with obstacle-induced perturbations to stretch and fold the fluid interface, promoting transverse transport. The optimized mixer, fabricated and experimentally validated, achieves a high mixing index (>0.85) under all Re conditions. This work provides valuable design insights for developing efficient, compact micromixers for micro-total analysis systems. Full article

Triticale (×Triticosecale Wittmack), a synthetic hybrid of wheat (Triticum spp.) and rye (Secale cereale), is a valuable dual-purpose crop for its high yield and stress tolerance. Introducing beneficial alien chromatin is crucial for expanding genetic diversity and improving cultivars. This study aimed to introduce Thinopyrum intermedium St genome chromatin into hexaploid triticale via trigeneric hybridization to develop novel germplasm. Six stable lines were selected from crosses between an octoploid wheat-Th. intermedium partial amphiploid line Maicao 8 and a hexaploid triticale cultivar Hashi 209. Agronomic traits were evaluated over two cropping seasons, revealing that the translocation lines exhibited superior agronomic performance compared to the parental triticales. These lines showed longer spikes, higher tiller numbers, and increased grain protein content, without compromising thousand-kernel weight. Cytogenetic analysis using sequential multicolor genomic in situ hybridization (smGISH), fluorescence in situ hybridization (FISH), and oligonucleotide probes, alongside validation with species-specific molecular markers, identified all six lines as St-R terminal translocation lines containing 14 rye chromosomes. Three lines carried a small terminal St segment on chromosome 1R, while the other three carried St segments on both 1RL and 4RS chromosomes. This work demonstrates that trigeneric hybridization is an effective strategy for inducing intergeneric recombination between Thinopyrum intermedium and rye chromosomes, leading to stable, small-segment terminal translocations. The developed St-R translocation lines represent a novel and valuable germplasm resource for enriching genetic diversity and breeding improved triticale cultivars with enhanced yield and quality traits. Full article

Collagenases can specifically degrade collagen, showing a wide application prospect in food, leather, waste utilization, biotechnology, and other industries. Currently, Hathewaya histolytica is commonly used in industry to produce collagenases, but its application is greatly limited by its pathogenicity. This study first identified five potential Pseudomonas-derived collagenases by sequence alignment. Bioinformatics tools were used to analyze their structures and functions. Heterologous expression of two P. chlororaphis-derived collagenases was achieved in E. coli, and their enzymatic properties were characterized. Bioinformatics analysis shows that the Pseudomonas-derived collagenases had low molecular weights (22.1~50.5 kDa) and good thermal stability (aliphatic index 73.73~88.81). Deletion of P. chlororaphis GP72ANO strain colP1 and colP2 genes had no significant effect on cell growth. The yields of collagenase ColP1 and ColP2 obtained from E. coli BL21(DE3) cultivation broth were 148 mg/L and 322 mg/L, respectively. The optimum temperature of each collagenase was 28 °C, and the soluble collagen activities of ColP1 and ColP2 were up to 42.64 U/mg and 21.21 U/mg, respectively. Collagenase ColP1 had the highest enzyme activity at pH 8, while collagenase ColP2 had the highest enzyme activity at pH 4. Metal ions such as Na⁺, K⁺, Mg²⁺, Ca²⁺, Ni²⁺, and Mn²⁺ inhibited the activity of collagenases to different degrees. This study successfully achieved recombinant expression and preliminary purification of Pseudomonas-derived collagenases in E. coli and explored their function and physicochemical properties. Full article

Synthesized by expressing natural collagen sequences in specific hosts, recombinant collagen exhibits multiple advantages, encompassing a higher content of bioactive domains, enhanced antioxidant activity, the absence of viral pathogens, favorable hydrophilicity, reproducible production, and low immunogenicity. Consequently, it has found extensive use in applications ranging from biomaterials and pharmaceuticals to skincare. This review systematically explores various expression systems for recombinant collagen, including those utilizing Escherichia coli, Pichia pastoris, plants, insect baculovirus, and mammalian cells. It provides a detailed comparison of their differences and commonalities in terms of production efficiency, post-translational modification capability, and cost-effectiveness. Key separation and purification techniques for recombinant collage-notably precipitation, affinity chromatography, ion-exchange chromatography, and gel filtration chromatography are further introduced, with an in-depth analysis of the applicable scenarios and purification outcomes for each method. Finally, the review comprehensively summarizes the characterization methods for both the physicochemical properties and biological functions of recombinant collagen. For physicochemical properties, techniques covered include scanning electron microscopy, micro-differential thermal analysis, circular dichroism spectroscopy, SDS-PAGE, mass spectrometry, and Fourier-transform infrared spectroscopy. For biological functions, the focus is on its roles and the corresponding assessment methods in processes such as cell proliferation, migration, adhesion, and wound healing. Building upon this comprehensive overview, current challenges facing recombinant collagen are identified, and future directions are proposed, emphasizing the need to reduce R&D costs, refine testing methods for cosmetic products, and improve safety evaluation protocols to advance the field. Full article

Natural bioactive peptides have emerged as pivotal candidates in modern science due to their multifaceted biological activities and versatile applications across biomedicine, biotechnology, and nutraceuticals. These molecules exhibit a broad pharmacological spectrum including antimicrobial, antiplatelet, antioxidant, antihypertensive, and antitumor properties, positioning them as potent therapeutic agents and essential functional food constituents. Compared to synthetic alternatives, their inherent structural diversity, biocompatibility, and biodegradability offer a superior safety profile by minimizing systemic toxicity and adverse effects. This review provides a comprehensive analysis of the primary natural reservoirs of these peptides, which encompass terrestrial flora and fauna as well as marine organisms and microorganisms, while elucidating their complex mechanisms of action and structure–function relationships. Furthermore, we evaluate contemporary methodologies for peptide identification and optimization, such as high-throughput proteomics, computational modeling, and strategic chemical modifications aimed at enhancing metabolic stability and bioavailability. Although bottlenecks in extraction, scalable production, and proteolytic susceptibility persist, recent breakthroughs in recombinant technology and rational design are facilitating their industrial translation. Finally, we discuss future perspectives focused on the synergy between artificial intelligence, nanotechnology, and sustainable circular economy strategies to maximize the therapeutic accessibility and functional efficacy of natural peptides. Full article

The considerable HIV-1 genetic diversity has several implications for viral adaptive and evolutionary capabilities. Its genetic diversity is due to its high mutational rates derived from the error-prone viral reverse transcriptase activity, which generates highly heterogeneous viral populations. Moreover, genetic diversity can also increase due to intra- or intersubtype viral genomic recombination following multiple infections. This study examines HIV-1 intersubtype recombinant viruses and their increased genomic diversity over a 12-month period in five individuals from São Paulo state, Brazil. We collected peripheral blood mononuclear cells once every three months from selected participants at five distinct visits. Molecular clones of 1.15 Kbp fragments of the Pol polyprotein, spanning the protease and a portion of the reverse transcriptase (RT) genes, were generated by bulk PCR. Pol sequences were used for evolutionary analysis, including phylogenetics (using TnT), genetic diversity (using Highlighter), and hypermutation frequency (using Hypermut). Recombination detection experiments were conducted with a jumping profile-hidden Markov model (jpHMM), SimPlot++, and RDP5. We observed great genetic diversity and frequent recombination events in all patients. Furthermore, most of the patients presented hypermutations. These findings highlight the dynamic nature of HIV-1 genetic diversity, driven by frequent recombination and hypermutation, which can accelerate viral adaptation and diversification, underscoring the challenges for treatment, prevention, and disease control. Full article

Filamentous fungi are widely used in biotechnological processes because they secrete significant amounts of protein, use inexpensive nutrient media, and are predictably scalable in technological processes. Penicillium verruculosum B1-537 (now renamed Talaromyces verruculosus) produces large amounts of secreted protein (up to 70 g/L) and is used for large-scale enzyme production. Although P. verruculosum has an excellent protein expression system under the control of a strong cbh1 promoter, some heterologous enzymes such as Aspergillus awamori glucoamylase (aaGlaA) are still produced in insufficient quantities (15–20% of the total secreted protein), and this limits the application of enzyme preparations derived from P. verruculosum strains in the alcohol industry for the enzymatic treatment of grain starch together with α-amylase. One of the well-known approaches to addressing this is signal peptide replacement to increase protein expression. Therefore, the aim of this study was to investigate the effectiveness of signal peptide replacement. Various signal peptides (SPs), which were previously used for other well-expressed heterologous proteins, such as xylanases, β-glucosidases, and others, were analyzed to determine their effect on aaGlaA secretion. Five plasmids containing signal peptide sequences fused to the glaA gene were constructed and used to transform P. verruculosum. The resulting strains were cultured and screened for protein content and glucoamylase activity. Copy number analysis was performed on the most productive strains. The best one was an SP of homologous glucoamylase in P. verruculosum (pvGlaA). The use of this particular SP increased the secretion of heterologous aaGlaA by 2.5 times when cultivating recombinant strains on cellulose-containing fermentation media for P. verruculosum. Thus, SP replacement is a useful way to increase expression levels in the P. verruculosum expression system. Application of this method in P. verruculosum could address some productivity issues and enable the large-scale production of other industrial and food enzymes. Full article

Ge-doped CIGSe absorbers were fabricated using a two-step process of depositing sputtered stacked Ge-doped CIGSe precursors and selenization annealing. The effects of Ge doping on the crystallinity as well as defects of CIGSe absorbers and the performance of CIGSe buffer-free solar cells were investigated. The results show that Ge doping significantly promotes the grain growth of CIGSe absorbers. Due to Ge loss via volatilization during selenization annealing, Ge residue is undetectable in Ge-doped absorbers. Ge doping offers an effective approach to improve CIGSe crystallinity without introducing notable impurity phases or Ge-related defects. However, Ge doping also induces Se loss, and excessive Se vacancy defects adversely affect the performance of the absorber. In addition, Ge doping increases the contact potential difference at CIGSe grain boundaries and is beneficial for reducing carrier recombination at these sites. Analysis of recombination rates in Ge-doped CIGSe buffer-free solar cells reveals that the combined effects of enhanced crystallinity and optimized electrical properties at grain boundaries effectively suppress the recombination in the space charge region, at the interface, and in the quasi-neutral region, leading to improved device performance. Full article

Sexual size dimorphism (SSD) refers to the phenomenon where males and females of the same species exhibit differences in overall or partial body size, and it is widespread among mammals, birds, reptiles, and fish. Notably, this dimorphism is significantly influenced by the sexually dimorphic secretion of growth hormone (gh), a key pituitary-derived growth regulator. Commonly, the secretion of gh is positively regulated by glucagon family members such as growth hormone-releasing hormone (ghrh) and adenylate cyclase-activating polypeptide 1 (adcyap1). To explore the stimulators for pituitary hormones (especially gh) in the teleost, we performed genome-wide identification and functional characterization of the glucagon family on Chinese tongue sole (Cynoglossus semilaevis) that exhibits typical female-biased sexual size dimorphism. Four members of adcyap1/vasoactive intestinal polypeptide(vip)/ghrh family and ten members of their receptor family were identified. Expression pattern analysis revealed high expression of adenylate cyclase-activating polypeptide 1b (adcyap1b) and its receptors in the brain. Moreover, two alternative splice variants for the adcyap1b gene were discovered, resulting from the skipping of exon 4. Following the acquisition of the two eukaryotic recombinant protein splice variants (ADCYAP1b_tv1 and ADCYAP_tv2) from HEK 293T cells, incubation experiments were conducted using C. semilaevis pituitary cell line. The results demonstrated that both variants promoted the expression of gh, pro-opiomelanocortin (pomc), and corticoliberin (crh), but ADCYAP1b_tv1 had a significantly stronger effect and uniquely stimulated prolactin (prl) and somatolactin (sl). This study demonstrates a functional divergence between the two ADCYAP1b splice variants in teleosts, with ADCYAP1b_tv1 acting as a more potent and versatile pituitary hormone stimulator. Further research on their receptor-binding affinity and downstream signaling pathways would be valuable for exploring the mechanism underlying sexual size dimorphism. Full article