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13 pages, 6819 KB  
Article
Novel Hepatopancreas-Predominant C-Type Lectin (LvCTL) Contributes to Resistance Against Vibrio parahaemolyticus in Shrimp Litopenaeus vannamei
by Ning Fu, Mengxin Xing, Yuyu Wang, Linwei Yang, Di Wang, Taolin Fan, Bang Xiao and Shengwen Niu
Fishes 2026, 11(8), 480; https://doi.org/10.3390/fishes11080480 - 18 Aug 2026
Viewed by 277
Abstract
C-type lectins (CTLs) are important pattern recognition receptors (PRRs) involved in innate immune defense in crustaceans. In this study, a novel C-type lectin, designated LvCTL, was identified and functionally characterized from Litopenaeus vannamei. Sequence analysis revealed that the open reading frame (ORF) [...] Read more.
C-type lectins (CTLs) are important pattern recognition receptors (PRRs) involved in innate immune defense in crustaceans. In this study, a novel C-type lectin, designated LvCTL, was identified and functionally characterized from Litopenaeus vannamei. Sequence analysis revealed that the open reading frame (ORF) of LvCTL is 495 bp in length and encodes a 164-amino acid polypeptide containing a typical C-type lectin-like domain but lacking the classical carbohydrate-binding motifs. Notably, two novel EPF motifs were identified in the CTLD region, suggesting a potential non-canonical ligand recognition pattern. Phylogenetic analysis revealed that LvCTL clustered with other crustacean CTLs. Tissue expression analysis revealed that LvCTL exhibited the highest transcript level in the hepatopancreas. After immune stimulation, LvCTL expression in the hepatopancreas was significantly regulated by LPS, Vibrio parahaemolyticus, Staphylococcus aureus, WSSV and Poly(I: C), indicating its involvement in antimicrobial immune responses. RNA interference assays showed that knockdown of LvCTL significantly increased the bacterial burden and reduced the survival rate of shrimp after V. parahaemolyticus infection. Furthermore, recombinant LvCTL displayed broad bacterial binding activity to Gram-negative and Gram-positive bacteria and induced calcium-dependent agglutination of V. parahaemolyticus and S. aureus. Taken together, these results demonstrate that LvCTL functions as an important immune recognition molecule and contributes to antibacterial defense against V. parahaemolyticus in L. vannamei. These findings broaden our understanding of the functional diversity of shrimp CTLs and their contributions to crustacean innate immunity. Full article
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19 pages, 3444 KB  
Article
Characterization of the Complete Mitochondrial Genome of Cricula andrei (Lepidoptera: Saturniidae) and Comparison with Other Lepidoptera Species
by Xiangrong Meng, Wentao Yang, Yuan Liu, Yongqi Zhang, Die Luo, Siyu Wei, Yifan Guo and Cen Qian
Curr. Issues Mol. Biol. 2026, 48(7), 741; https://doi.org/10.3390/cimb48070741 - 21 Jul 2026
Cited by 1 | Viewed by 283
Abstract
As the second largest order of Insecta, Lepidoptera is an important component of the ecosystems. However, there are few data on the mitochondrial genomes of Saturniidae. Here, the complete mitochondrial genome of Cricula andrei was sequenced and characterized. It was 15,324 bp in [...] Read more.
As the second largest order of Insecta, Lepidoptera is an important component of the ecosystems. However, there are few data on the mitochondrial genomes of Saturniidae. Here, the complete mitochondrial genome of Cricula andrei was sequenced and characterized. It was 15,324 bp in length, containing 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs and a control region (AT-rich region). The control region had an AT content of 90.40%, and the conserved ATAGA sequence guided a 19 bp poly-T. Amino acid composition analysis showed that Ile, Leu, Phe and Asn were the most frequent amino acids, and codon usage analysis revealed a preference for A/U-ending codons. Phylogenetic trees constructed by Bayesian inference and Maximum likelihood methods indicated that C. andrei is grouped with C. trifenestrata and supported the current taxonomic placement of Cricula within the family. The enrichment of the mitochondrial genome database of Lepidoptera will help to better understand the genetic and evolutionary relationships of lepidopteran populations, as well as related taxonomic issues. Full article
(This article belongs to the Section Bioinformatics and Systems Biology)
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23 pages, 2313 KB  
Article
Effects of Amino Acid Point Mutations on the Local Hydrophobicity, Structural Stability, and Conformational Flexibility of P-Glycoprotein
by Alexandra Ioana Năstasie and Adriana Isvoran
Biomolecules 2026, 16(7), 1046; https://doi.org/10.3390/biom16071046 - 17 Jul 2026
Viewed by 493
Abstract
P-glycoprotein (P-gp, ABCB1) plays a central role in multidrug resistance and drug pharmacokinetics. In this study, an integrated computational analysis of point amino acid substitutions across the P-gp sequence was performed to evaluate their predicted pathogenicity and structural impact. Variant classification using AlphaMissense [...] Read more.
P-glycoprotein (P-gp, ABCB1) plays a central role in multidrug resistance and drug pharmacokinetics. In this study, an integrated computational analysis of point amino acid substitutions across the P-gp sequence was performed to evaluate their predicted pathogenicity and structural impact. Variant classification using AlphaMissense and PolyPhen-2 revealed concordant predictions for a substantial subset of amino acid substitutions, with 21 variants consistently classified as benign and 13 as pathogenic, while discrepancies for other variants reflected methodological differences between the tools. Notably, substitutions located in transmembrane domains were more frequently predicted to be deleterious compared with those in cytoplasmic or extracellular regions, consistent with the structural and functional constraints imposed on membrane-spanning helices. Changes in local hydropathicity, average flexibility, protein stability (ΔΔG), hydrogen-bonding patterns, surface hydrophobicity and electrostatic potential distributions were also evaluated. Stability predictions obtained using I-Mutant2.0 and DynaMut2.0 indicated that many substitutions tend to destabilize P-gp, although differences in ΔΔG values were observed between methods due to distinct algorithmic approaches. Structural superposition analyses demonstrated generally minor backbone deviations, yet local alterations in surface hydrophobicity, electrostatic potential, and hydrogen bond networks were evident. These physicochemical perturbations, even when subtle, may influence conformational dynamics and coupling between nucleotide-binding and transmembrane domains. Overall, these findings suggest that single amino acid substitutions may alter the local structural environment of P-gp and could potentially influence its transport function. Full article
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24 pages, 2581 KB  
Article
Assessment of Enhanced Silicate Application for Improved Pest and Disease Resistance in Commercial Almond Production, Allowing for Sustainable Waste Management
by Manjula Nishantha Udagepolage Don, Singarayer Florentine, Chris Turville and Kithsiri Dassanayake
Horticulturae 2026, 12(7), 868; https://doi.org/10.3390/horticulturae12070868 - 16 Jul 2026
Viewed by 546
Abstract
The sustainable management of almond (Prunus dulcis) hulls and shells represents a major challenge for the global almond industry. Although almond hulls possess considerable nutritional value and can be used as livestock feed, concerns about pesticide residues limit their utilisation and [...] Read more.
The sustainable management of almond (Prunus dulcis) hulls and shells represents a major challenge for the global almond industry. Although almond hulls possess considerable nutritional value and can be used as livestock feed, concerns about pesticide residues limit their utilisation and pose environmental and economic disposal challenges. Therefore, alternative crop protection strategies that reduce reliance on chemical pesticides while maintaining productivity are required. Silicon has been widely reported to enhance plant resistance against biotic and abiotic stresses, improve nutrient utilisation, and increase crop productivity. This study evaluated the effects of an enhanced potassium silicate formulation applied through fertigation on pest and disease incidence, plant performance, and kernel yield in a commercial almond orchard over two consecutive growing seasons. The formulation contained potassium silicate (50% w/v), amino acids (42% w/v), Complex Polymeric Poly-Hydroxy Acid (CPPA) (1.5% w/v), and water. Treatments were applied twice per season at a rate of 30 L ha−1 and compared with a grower-standard management program. Silicon-treated trees exhibited significantly lower levels of microbial disease damage in both leaves and mature nuts compared with untreated controls. Across the two growing seasons, pest- and disease-related damage to nuts was reduced by up to 59%. Silicon treatment also resulted in substantial increases in oven-dried kernel weight, ranging from 19% to 33% across the evaluated almond varieties. No adverse effects were observed on flower-to-nut conversion, chlorophyll content, kernel nutritional quality, or leaf nutrient status. The findings demonstrate that enhanced potassium silicate fertigation can improve pest and disease resistance while increasing kernel yield in commercial almond production systems. The technology offers a promising strategy for reducing reliance on chemical pesticides and supporting the sustainable utilisation of almond by-products, including their use in livestock feed and bioenergy production. Full article
(This article belongs to the Section Plant Pathology and Disease Management (PPDM))
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25 pages, 5648 KB  
Article
PBAT Microplastics Modulate Oxidative Stress and Plant–Fungus Interactions in Wheat Under Metolachlor Exposure
by Olga Rusiecka and Przemysław Bernat
Appl. Sci. 2026, 16(13), 6569; https://doi.org/10.3390/app16136569 - 1 Jul 2026
Viewed by 295
Abstract
Microplastics (MPs) and pesticides increasingly co-occur in agricultural ecosystems, where they may jointly affect plant physiology and plant–microorganism interactions. This study investigated the individual and combined effects of biodegradable poly(butylene adipate-co-terephthalate) (PBAT), the herbicide metolachlor (MET), and the beneficial fungus Trichoderma harzianum KKP [...] Read more.
Microplastics (MPs) and pesticides increasingly co-occur in agricultural ecosystems, where they may jointly affect plant physiology and plant–microorganism interactions. This study investigated the individual and combined effects of biodegradable poly(butylene adipate-co-terephthalate) (PBAT), the herbicide metolachlor (MET), and the beneficial fungus Trichoderma harzianum KKP 534 on wheat (Triticum aestivum). Plant growth, physiological responses, chlorophyll content, cell membrane damage, antioxidant enzyme activities and selected metabolomic and lipidomic biomarkers were evaluated. High PBAT concentrations negatively affected wheat growth by reducing root and shoot length and increasing oxidative stress, as evidenced by elevated TBARS levels, increased antioxidant enzyme activities (POD, GST, CAT, and SOD), and enhanced membrane damage. Metabolomic and lipidomic analyses further revealed stress-associated changes in amino acid metabolism and membrane lipid remodelling. PBAT also adsorbed MET and 2,4-di-tert-butylphenol (DTBP), potentially altering their bioavailability and environmental behaviour. Although T. harzianum KKP 534 promoted plant growth and enhanced antioxidant responses under control conditions, these beneficial effects were attenuated in the presence of PBAT MP. The results suggest that biodegradable microplastics may influence plant–microbe interactions and modify pesticide dynamics under controlled conditions, highlighting the need for further studies in soil-based systems. Full article
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11 pages, 2000 KB  
Article
Molecular Characterization of Group II Interferon, IFNc, in Largemouth Bass (Micropterus salmoides) and Its Enhancement of Cell Viability Following Micropterus salmoides Rhabdovirus (MSRV) Infection
by Qihuan Zhang, Chang Wei, Jiashu Li, Yifei Wei, Jianfei Huang, Mingzhu Pan, Yang Xu and Zhitao Qi
Fishes 2026, 11(7), 376; https://doi.org/10.3390/fishes11070376 - 24 Jun 2026
Cited by 1 | Viewed by 425
Abstract
Interferons (IFNs) play vital roles in antiviral immunity, yet the functional diversity of type I IFNs in teleosts remains incompletely characterized. In this study, we identified and characterized a group II type I interferon, designated IFNc (MsIFNc), from largemouth bass (Micropterus salmoides [...] Read more.
Interferons (IFNs) play vital roles in antiviral immunity, yet the functional diversity of type I IFNs in teleosts remains incompletely characterized. In this study, we identified and characterized a group II type I interferon, designated IFNc (MsIFNc), from largemouth bass (Micropterus salmoides). The cDNA sequence of MsIFNc is 660 bp in length, encoding a 184-amino-acid polypeptide containing a signal peptide and four conserved cysteines predicted to form two disulfide bonds. Phylogenetic analysis confirmed its classification within the teleost IFNc subgroup. Tissue expression profiling revealed constitutive MsIFNc transcription in all examined tissues, with the highest levels in the liver, intestine, and spleen. Moreover, MsIFNc expression was significantly upregulated in the spleen following polyinosinic–polycytidylic acid (polyI:C) stimulation. Recombinant MsIFNc (rMsIFNc) was successfully expressed in Pichia pastoris and significantly enhanced the viability of primary hepatocytes infected with Micropterus salmoides rhabdovirus (MSRV). These results demonstrate that IFNc is an important component of the immune response in largemouth bass, providing a basis for understanding the function of fish IFNc. Full article
(This article belongs to the Special Issue Advances in the Immunology of Aquatic Animals)
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25 pages, 2647 KB  
Article
Enhanced Physico-Mechanical Properties of Sericin–PVA Composite Films with a Potential Antibacterial and Controlled Drug Release Features for Wound Dressing
by Kanono Comet Manesa, Simiso Dube and Mathew Muzi Nindi
Int. J. Mol. Sci. 2026, 27(12), 5216; https://doi.org/10.3390/ijms27125216 - 9 Jun 2026
Viewed by 362
Abstract
The application of silk sericin as a polymeric biomaterial has recently gained interest, although its film was found to be fragile, exhibiting brittleness when subjected to relatively slight stress, and it also displayed higher water solubility. This study focused on the enhanced physico-mechanical [...] Read more.
The application of silk sericin as a polymeric biomaterial has recently gained interest, although its film was found to be fragile, exhibiting brittleness when subjected to relatively slight stress, and it also displayed higher water solubility. This study focused on the enhanced physico-mechanical properties of the three films obtained by the crosslinking of sericin protein from three silkworm cocoons with poly (vinyl alcohol) (PVA) to reduce phase separation and solubilization of the films by promoting miscibility between sericin and PVA. The findings demonstrated how crosslinking with glutaraldehyde enhanced thermal stability and tensile strength and controlled the solubility of the three sericin–PVA films. The sericin from G. postica, G. rufobrunnea, and Argema mimosae is composed of serine, aspartic acid, and glutamic acid, which make up 80% of the total polar amino acids. X-ray diffraction (XRD) patterns showed that sericin–PVA films have semicrystalline features, representing amorphous and crystalline regions. The XRD results also indicated that the Saturniidae sericin–PVA film (Sat-SPF), Gonometa postica sericin–PVA film (GP-SPF), and Gonometa rufobrunnea sericin–PVA film (GR-SPF) have crystallinity percentages of 66.4%, 55.9%, and 17.7%, respectively. The moisture vapor transmission rate (MVTR) values observed in this study ranged from 991.2 to 5160 g/m2/24 h, indicating that these films can effectively regulate moisture levels in wounds. The swelling capacity of the three sericin–PVA composite films depends on the crosslinking density of their structures and was also found to be sensitive to the pH of the aqueous media, demonstrating their hydrophilic nature and potential use in drug delivery systems. The water vapor permeability of sericin–PVA films increased with higher environmental relative humidity (RH) and moisture content within the films. The elongation at break for GP-SPF (107.2% ± 3.1) and Sat-SPF (73.0% ± 4.1) was significantly higher than in GR-SPF (29.3% ± 2.3). However, their tensile strength and elastic modulus were lower than those of GR-SPF. These results show that the number of polar groups (amino and hydroxyl groups) from both sericin and PVA influences all the properties of the sericin–PVA composite films. The three sericin–PVA solutions were found to have antibacterial efficacy against three Gram-positive and one Gram-negative bacteria over 24 h. Scanning electron microscopy (SEM) images revealed a rough surface with a granular network pattern, which supports the potential use of sericin–PVA films for cell adhesion and proliferation, which are essential for biomedical wound dressing applications. Full article
(This article belongs to the Section Materials Science)
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17 pages, 3607 KB  
Article
Conformational Dynamics and Catalytic Behavior of Cysteine Proteases Immobilized on Alginate-Based Graft Copolymers: A Structure–Property Study
by Maria S. Lavlinskaya, Andrey V. Sorokin, Anastasia N. Dubovitskaya, Sofia S. Stepanova, Maxim S. Kondratyev, Marina G. Holyavka, Yuriy F. Zuev and Valeriy G. Artyukhov
Macromol 2026, 6(2), 40; https://doi.org/10.3390/macromol6020040 - 8 Jun 2026
Viewed by 670
Abstract
Cysteine proteases (bromelain, ficin, and papain) are widely used in biotechnology and medicine, but their application is limited by rapid autolysis and oxidative inactivation. This study aimed to develop effective supports for these enzymes based on graft copolymers of sodium alginate and poly( [...] Read more.
Cysteine proteases (bromelain, ficin, and papain) are widely used in biotechnology and medicine, but their application is limited by rapid autolysis and oxidative inactivation. This study aimed to develop effective supports for these enzymes based on graft copolymers of sodium alginate and poly(N-vinylpyrrolidone) (SA-g-PVP) and to elucidate the structure–property relationships governing immobilization efficiency, catalytic activity, and storage stability. Copolymers were synthesized via radical solution polymerization under optimized conditions. Enzymes were immobilized by physical adsorption, and the resulting complexes were characterized by Fourier-transform infrared (FTIR) spectroscopy, protein content assays, proteolytic and amidase activity measurements, and molecular docking. The graft copolymer with a smaller particle size in solution provided a larger accessible surface area, leading to higher bromelain and papain loading. Ficin showed the opposite trend due to its unique surface amino acid composition. Immobilization dramatically increased storage stability: half-life values for bromelain, ficin, and papain reached up to 20, 14, and 14 days, respectively, compared to 1–3 days for the free enzymes. Molecular docking revealed that the dense polymer shell stabilizes the enzyme tertiary structure by forming multiple contacts with internal cavities and tunnels, thereby preventing autolysis and conformational unfolding. Collectively, these findings demonstrate that SA-g-PVP copolymers are promising, non-toxic supports for cysteine proteases, with ficin showing up to 100% activity recovery, making them suitable for food, cosmetic, and biomedical applications. Full article
(This article belongs to the Special Issue Advanced Functional Biomacromolecules in Biosensing)
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21 pages, 2054 KB  
Review
Polymeric Delivery System for mRNA Therapeutics: Design Principles and Recent Advances
by Sidi Bao, Irene Rose Reuben, Josie Ward, Wenxin Wang and Xianqing Wang
Genes 2026, 17(6), 646; https://doi.org/10.3390/genes17060646 - 31 May 2026
Cited by 1 | Viewed by 1265
Abstract
Messenger RNA (mRNA) therapeutics are redefining treatment approaches in vaccines, cancer immunotherapy, protein replacement, and gene editing. Lipid nanoparticles have enabled early clinical successes, but they can be limited by liver-dominant biodistribution, long-term storage stability, and systemic tolerability. Polymeric delivery systems offer a [...] Read more.
Messenger RNA (mRNA) therapeutics are redefining treatment approaches in vaccines, cancer immunotherapy, protein replacement, and gene editing. Lipid nanoparticles have enabled early clinical successes, but they can be limited by liver-dominant biodistribution, long-term storage stability, and systemic tolerability. Polymeric delivery systems offer a versatile alternative, with tunable physicochemical properties enabling precise control over mRNA complexation, protection, release, and targeting. This review examines recent progress across polyethyleneimine derivatives, poly(β-amino ester)s, poly(amino acid)s, polyesters, dendrimers, charge-altering releasable transporters, and lipid-polymer hybrids. We highlight strategies such as structural modification, stimuli-responsive designs, and high-throughput polymer screening that enhance stability, reduce cytotoxicity, and enable organ- or cell-specific delivery. Addressing challenges in immunogenicity, biodistribution, and manufacturing scalability will be pivotal to translating these innovations into safe and effective mRNA therapeutics. Full article
(This article belongs to the Section RNA)
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25 pages, 4157 KB  
Article
Phosphate-Surface-Modified Silica Nanoparticles for 5-Fluorouracil as a Prolonged Drug Delivery System
by Aleksandra Lis, Arkadiusz Surażyński, Przemysław Koźmiński and Paweł Szymański
Pharmaceuticals 2026, 19(5), 802; https://doi.org/10.3390/ph19050802 - 21 May 2026
Cited by 1 | Viewed by 510
Abstract
Background/Objectives: This paper describes the synthesis of silica nanoparticles (SiNPs) and their surface modification with amino and phosphate groups (SiNPs-NH2-PO3). The functionalized nanoparticles were subsequently loaded with the anticancer drug 5-fluorouracil (SiNPs-NH2-PO3-5-FLU) and further modified [...] Read more.
Background/Objectives: This paper describes the synthesis of silica nanoparticles (SiNPs) and their surface modification with amino and phosphate groups (SiNPs-NH2-PO3). The functionalized nanoparticles were subsequently loaded with the anticancer drug 5-fluorouracil (SiNPs-NH2-PO3-5-FLU) and further modified with PEG2000 (SiNPs-NH2-PO3-5-FLU-PEG2000). Methods: In this study, a one-step, two-phase, sol–gel method carried out at room temperature was used to synthesize the nanoparticles. The size and surface zeta potential of the created SiNPs were determined by DLS measurements. HPLC was used to determine the amount of drug loaded into silica nanoparticles and the drug release profile in two different pH environments (slightly acidic and physiological). Based on physicochemical characteristics, the SiNPs-NH2-PO3-5-FLU and SiNPs-NH2-PO3-5-FLU-PEG2000 formulations were chosen for comprehensive characterization. The cytotoxicity of the studied complexes was assessed in MCF7 breast cancer cells, while their ability to induce apoptosis in those cells was examined using specific immunofluorescence markers: active caspase-7, active poly(ADP-ribose) polymerase (PARP), and p53 protein. Results: Our findings demonstrate that SiNPs-NH2-PO3-5-FLU can induce a stronger apoptotic response than free 5-FLU at equivalent concentrations. We observed that drug release occurs not only under physiological conditions but is further enhanced in a mildly acidic environment (pH 5.0), characteristic of the tumor microenvironment. Conclusions: Most 5-fluorouracil formulations are administered as injectable solutions, resulting in systemic exposure and significant adverse effects. However, their encapsulation within nanoparticles could favor preferential drug release in the acidic tumor microenvironment, thus supporting targeted therapy and reducing toxicity to healthy tissues. Moreover, PEGylation of the nanoformulation allows prolonged and controlled release. Full article
(This article belongs to the Section Pharmaceutical Technology)
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15 pages, 2527 KB  
Article
Genome Characterization of a Novel Hepe-like Virus and a Rhabdovirus Identified in Macrosteles fascifrons
by Danfeng Ge, Zhi Ni, Jingya Wang, Qianqian Li, Yuting Jia, Xinyu Wei, Chuanhao Hu, Ruijun Fan, Wangxing Yang, Shishuai Lin, Zhiyuan Wu, Renyi Liu and Jiajing Xiao
Insects 2026, 17(5), 479; https://doi.org/10.3390/insects17050479 - 8 May 2026
Viewed by 576
Abstract
Macrosteles fascifrons, a representative aster leafhopper frequently detected in rice-growing environments, is an economically significant insect that inhabits rice fields and plays a role in the ecology of crop pests and disease transmission. To expand the understanding of viral diversity associated with [...] Read more.
Macrosteles fascifrons, a representative aster leafhopper frequently detected in rice-growing environments, is an economically significant insect that inhabits rice fields and plays a role in the ecology of crop pests and disease transmission. To expand the understanding of viral diversity associated with the aster leafhopper, we analyzed its virome using deep transcriptome sequencing. In addition to several previously reported viruses, we identified two previously unreported RNA viruses, tentatively designated as Macrosteles fascifrons hepe-like virus 1 (MfHV1) and Macrosteles fascifrons rhabdovirus 1 (MfRV1). The complete genome sequences of both genomes were obtained using overlapping RT-PCR and rapid amplification of cDNA ends. Excluding the poly(A) tail, the genome of MfHV1 is 6688 nucleotides in length and exhibits a genomic organization characteristic of the family Hepeviridae, comprising three major open reading frames (ORFs) that encode a putative nonstructural polyprotein, a capsid protein, and a small accessory protein. The ORF encoding the capsid protein partially overlaps with the ORF encoding the small accessory protein, a genomic feature commonly observed in hepe-like viruses. The genome of MfRV1 is 14,984 nucleotides in length and displays the canonical genomic organization of the family Rhabdoviridae. An additional accessory ORF was identified between the putative M and G genes. Phylogenetic analysis based on polyprotein sequences placed MfHV1 within the Hepeviridae, most closely related to insect-associated hepe-like viruses, whereas MfRV1 clustered within the subfamily Deltarhabdovirinae. According to ICTV guidelines, virus classification is based on a combination of sequence divergence, phylogenetic relationships, and genome organization. MfHV1 and MfRV1 share low amino acid sequence identities with known viruses (maximum 36.07% for the MfHV1 polyprotein and 47.7% for the MfRV1 RNA-dependent RNA polymerase). Based on sequence divergence, genome organization, and phylogenetic placement, these viruses are classified as putative novel members of their respective families. This study expands the diversity of virus-associated sequences detected in M. fascifrons and provides additional genomic resources for understanding insect-associated RNA viruses. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
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16 pages, 3356 KB  
Article
Molecular Characterization and In Vitro Functional Analysis of a 1-Cys Peroxiredoxin 6 from the Whiteleg Shrimp Penaeus vannamei
by Gunasekara Chathura Wikumpriya, W. S. P. Madhuranga and Chan-Hee Kim
Genes 2026, 17(4), 428; https://doi.org/10.3390/genes17040428 - 6 Apr 2026
Viewed by 1371
Abstract
Background/Objectives: Peroxiredoxins (Prxs) are key antioxidant enzymes involved in cellular redox homeostasis. Prx6 is a multifunctional member of the Prx family that has been reported in other organisms to possess glutathione peroxidase and phospholipase A2 (PLA2)-related activities. However, the structural [...] Read more.
Background/Objectives: Peroxiredoxins (Prxs) are key antioxidant enzymes involved in cellular redox homeostasis. Prx6 is a multifunctional member of the Prx family that has been reported in other organisms to possess glutathione peroxidase and phospholipase A2 (PLA2)-related activities. However, the structural and immunological roles of 1-Cys Prx6 in crustaceans remain poorly understood. This study aimed to identify and characterize a Prx6 gene from Penaeus vannamei (PvPrx6) and to evaluate its potential involvement in antioxidant defense. Methods: PvPrx6 cDNA was identified and analyzed using bioinformatics and AlphaFold2 modeling. Tissue distribution and transcriptional responses to lipopolysaccharide (LPS), poly(I:C), and peptidoglycan (PGN) were examined by RT-qPCR. Recombinant PvPrx6 (rPvPrx6) was expressed in Escherichia coli, and its antioxidant activity was evaluated in vitro using a metal-catalyzed oxidation (MCO) assay. Results: PvPrx6 encodes a 219-amino-acid protein containing conserved AhpC/TSA and 1-Cys Prx domains. Sequence comparison and 3D modeling revealed conserved peroxidase (Thr41, Cys44, Arg127) and residues (His23, Lys29, Asp135) corresponding to the reported PLA2-associated motif. Structural analysis suggested that Lys29 occupies a position corresponding to the Ser32 residue of human Prx6, although this did not imply functional equivalence. PvPrx6 transcripts were highly expressed in the lymphoid organ and hepatopancreas and were significantly induced at 12 h following immune challenge. rPvPrx6 exhibited dose-dependent protection against hydroxyl radical-mediated DNA damage under the experimental conditions. Conclusions: Collectively, these findings suggest that PvPrx6 retains conserved structural characteristics of Prx6 proteins and may contribute to antioxidant defense in P. vannamei. However, further studies are required to validate its enzymatic activity and in vivo functional roles. Full article
(This article belongs to the Special Issue Genetic Insights into Immunity and Pathogen Resistance)
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29 pages, 4262 KB  
Article
Synthesis of Azatide Dipeptide Analogs and Their Stability and Reactivity in 98% w/w Sulfuric Acid
by Sara Seager, Maxwell D. Seager, Ton Visser, Bartjan Koning, Jim van Wiltenburg, Martin Poelert and Janusz J. Petkowski
Molecules 2026, 31(7), 1196; https://doi.org/10.3390/molecules31071196 - 3 Apr 2026
Viewed by 729
Abstract
Life as we know it depends on peptide and nucleic acid polymers built from a limited set of backbone residues, yet planetary environments beyond Earth motivate consideration of alternative chemical frameworks for genetic- and protein-like polymers. In this context, we synthesize four azatide [...] Read more.
Life as we know it depends on peptide and nucleic acid polymers built from a limited set of backbone residues, yet planetary environments beyond Earth motivate consideration of alternative chemical frameworks for genetic- and protein-like polymers. In this context, we synthesize four azatide dipeptide analogs (Alaa-Glya (1), Glya-Alaa (2), Glya-Glya (3), and Alaa-Alaa (4)) as candidate backbone motifs for non-standard biologically relevant polymers. We then systematically assess their stability and reactivity in 98% w/w sulfuric acid, a solvent relevant to Venusian cloud chemistry. We assess the stability of the azatides via 1H and 13C NMR spectroscopy supported with ELSD-LCMS. We monitor the stability of the compounds over periods from hours to two weeks at room temperature and at elevated temperatures (50–80 °C). All four azatides readily dissolve in 98% w/w D2SO4 and are generally stable at room temperature. Glya-Alaa (2) shows no detectable degradation over a two-week incubation in 98% w/w sulfuric acid. The other three azatide analogs display only minor decomposition. ELSD-LCMS measurements qualitatively confirm the NMR results, revealing only minor-to-moderate loss of parent compounds after two weeks at room temperature. At higher temperatures, representative of the lower Venusian cloud deck, the stability of the azatides decreases dramatically. All four compounds undergo significant decomposition at 50 °C and completely degrade within one to two weeks at 80 °C. Our findings indicate that azatides, despite being generally stable in concentrated sulfuric acid at room temperature, lack the thermal stability that might be required to serve as viable backbone motifs for biological polymers in environments spanning the full temperature range of Venusian clouds. Full article
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18 pages, 3745 KB  
Article
Amino-Functionalized Poly(2-Ethyl-2-Oxazoline)-Ran-Poly[2-(3-Butenyl)-2-Oxazoline] Copolymers Used as Non-Viral Vectors for Nucleic Acid Delivery: Impact of Polymer Structure and Composition
by Denitsa Hristova, Natalia Oleszko-Torbus, Maria Petrova, Agnieszka Kowalczuk, Iva Ugrinova, Stanislav Rangelov and Emi Haladjova
Polymers 2026, 18(4), 536; https://doi.org/10.3390/polym18040536 - 22 Feb 2026
Cited by 1 | Viewed by 929
Abstract
In this work, we designed non-viral gene delivery vector systems based on three poly(2-ethyl-2-oxazoline)-ran-poly[2-(3-butenyl)-2-oxazoline] copolymers functionalized by primary, secondary, and tertiary amino groups. The impact of copolymer structure and composition was sought through the examination of basic physicochemical and biological parameters. The complexation [...] Read more.
In this work, we designed non-viral gene delivery vector systems based on three poly(2-ethyl-2-oxazoline)-ran-poly[2-(3-butenyl)-2-oxazoline] copolymers functionalized by primary, secondary, and tertiary amino groups. The impact of copolymer structure and composition was sought through the examination of basic physicochemical and biological parameters. The complexation ability of copolymers with plasmid DNA was studied by ethidium bromide quenching assay. The polyplex particles size and ζ-potential were determined by dynamic and electrophoretic light scattering. The release ability of copolymers was assessed by competitive displacement of DNA using dextran sulfate. The biological performance of amino-functionalized poly(2-ethyl-2-oxazoline)-ran-poly[2-(3-butenyl)-2-oxazoline] based gene delivery systems was evaluated, and their behavior under various environmental conditions, such as pH and ionic strength, was investigated. Cytotoxicity was assessed in two human lung-derived cell lines, and the ability of the copolymers to mediate plasmid DNA delivery and expression was examined. The resulting polyplex nanoparticles exhibited the ability to release DNA molecules and sensitivity to alterations in pH and ionic strength. All systems showed high biocompatibility and were able to mediate plasmid DNA delivery, resulting in detectable EGFP expression in vitro. The vector properties were found to be driven by a multifactorial interplay among hydrophobic character, thermoresponsive behavior, polymer mobility, charge accessibility, intracellular environmental responsiveness, secondary structure effects, etc. The copolymer bearing primary amino groups displayed a distinct balance between DNA binding and release, characterized by moderate complex stability and enhanced sensitivity to environmental changes. These findings provide mechanistic insight into how amino functionality and polymer structure influence the structure–property–behavior relationships of polyoxazoline-based non-viral gene delivery systems. Full article
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16 pages, 3673 KB  
Article
Generation of Schlafen 8-Specific Antibodies
by Juan Carlos Silva-Espinoza, Mauricio I. Rodriguez Rodriguez, Claire Eunise Perucho, Brian A. Terrazas, Carlos Valenzuela, Stephany Palos Vargas, Andrea Carlin, Diana L. Prospero, Giulio Francia and Manuel Llano
Antibodies 2026, 15(1), 16; https://doi.org/10.3390/antib15010016 - 21 Feb 2026
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Abstract
Background/Objectives: Schlafen (SLFN) 8 and SLFN9 are mouse members of the Schlafen protein family, believed to have arisen through a gene duplication event. The physiological roles of these proteins remain poorly defined, in part due to the absence of reliable, commercially available [...] Read more.
Background/Objectives: Schlafen (SLFN) 8 and SLFN9 are mouse members of the Schlafen protein family, believed to have arisen through a gene duplication event. The physiological roles of these proteins remain poorly defined, in part due to the absence of reliable, commercially available antibodies for their detection. Methods: To develop specific antibodies, we performed an amino acid sequence alignment of these proteins and identified a thirteen amino acids long peptide predicted by AlphaFold modeling and hydropathicity analysis to be surface-exposed in both SLFN proteins. The SLFN8 peptide was conjugated to KLH and used to immunize mice, employing Poly(I:C) as an adjuvant. Results: We verified the anti-SLFN8 antibody specificity in mouse tissues, engineered human cells, and recombinant proteins by different immunodetection techniques, including Western blotting, immunoprecipitation, immunohistochemistry, and ELISA. Furthermore, splenocytes from immunized mice were used to generate hybridomas that secreted IgG antibodies with SLFN8-peptide specificity, as assumed by ELISA. Conclusions: Our results demonstrate that the identified peptide is highly immunogenic and capable of eliciting antibodies that distinguish between these two exceedingly similar proteins in a broad group of immunodetection techniques. Full article
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