A bio-safe multiple antigenic peptide (MAP) enzyme-linked immunoassay for the detection of antibodies to infectious bronchitis virus in chickens

H-Y antigen-based immuno-segregation strategies for bovine X sperm enrichment

Insemination of sperm bearing X and Y chromosomes prior to sexual pre-selection significantly impacts the livestock industry economically. Fluorescence-activated cell sorting (FACS) is a widely accepted technology that sorts sperm with over 90 % accuracy. High costs and potential damage to sperm limit the application of flow cytometry. Consequently, flow cytometry has been replaced by less intrusive and more affordable immunological methods. The present study hypothesizes that antibodies raised against male-enhanced antigen-1 (MEA-1) peptide of Bos indicus will specifically bind to bovine Y sperm, thus assisting in the enrichment of X sperm. A solid surface strategy (SSS) was employed to enrich the X chromosome-bearing spermatozoa of Bos indicus, utilizing purified IgG anti-peptide (MEA P-1) antibodies alongside commercial Human MEA-1 antibodies for comparison. A quantitative SYBR green real-time PCR assay targeting the Y chromosome-specific SRY gene and the X chromosome-specific PLP gene was conducted to determine the ratio of X and Y sperm in the enriched semen samples. The solid surface strategy using commercially available Human MEA-1 antibodies and anti-MEA P-1 antibodies yielded 34.72 ± 6.74 (X: Y; 73:27) and 20.02 ± 4.08 (X: Y; 64:36) % of X sperm enrichment, respectively. The mean percentage of X chromosome content in an unsorted semen sample and cow bull blood was 50.53 ± 0.19 and 49.90 ± 1.27, respectively, aligning with an expected ratio of 1:1. The sperm viability analysis using computer-assisted semen analyzer (CASA) for motility parameters and the hypo-osmotic swelling (HOS) test showed acceptable sperm viability post-treatment with anti-MEA P-1 antibodies. The study evaluated the efficacy and utility of anti-peptide MEA P-1 antibodies as an alternate approach for bovine X sperm enrichment.

Designing, Synthesis and In Vitro Antimicrobial Activity of Peptide Against Biofilm Forming Methicillin Resistant Staphylococcus aureus

Increasing antimicrobial resistance and residue in an ecosystem is a huge threat to human as well as animal possibly inviting an uncontrollable outbreak and spoiling food. Use of alternative approaches in tackling the resistance problem has shown promising results in recent past. The present study was targeted to develop and evaluate the use synthetic peptide against biofilm forming methicillin resistant Staphylococcus aureus (MRSA). Peptide evaluation included determination of MIC, time kill kinetics, lysis activity, cell cytotoxicity assay, effect on biofilm formation, mechanism of action, thermo-stability and pH stability. Initially, a synthetic antimicrobial peptide, RWWKARIRL (ANLP-V3) was designed using bioinformatics tools and synthesized by solid phase synthesis using Fmoc chemistry. Peptide was found to exhibit antibacterial activity at 19.5 µg/mL concentration against both ATCC & clinical isolates of S. aureus. The time kill kinetic studies revealed > 99% inhibition of growth after 3 h at MIC, whereas 100% cell inhibition was seen at 2 h at 2 × MIC and 4 × MIC. No cytotoxicity was observed against mice RBCs as well as Vero cells at 2 × MIC. The AMP was found to be thermo-stable as well as pH stable at a wide range. Field emission scanning electron microscopy study demonstrates cell morphological alterations in AMP treated cells indicating membrane interacting nature of AMP. At MIC concentration, effective inhibition of biofilm formation in ATCC strains was seen. In conclusion, designed peptide might be effective antimicrobial agent against methicillin resistant biofilm forming S. aureus underlining possibilities of its preclinical development against mastitis in dairy animals.

Apoptin NLS2 homodimerization strategy for improved antibacterial activity and bio-stability

The emergence of antibiotic resistance prompts exploration of viable antimicrobial peptides (AMPs) designs. The present study explores the antimicrobial prospects of Apoptin nuclear localization sequence (NLS2)-derived peptide ANLP (PRPRTAKRRIRL). Further, we examined the utility of the NLS dimerization strategy for improvement in antimicrobial activity and sustained bio-stability of AMPs. Initially, the antimicrobial potential of ANLP using antimicrobial peptide databases was analyzed. Then, ANLP along with its two homodimer variants namely ANLP-K1 and ANLP-K2 were synthesized and evaluated for antimicrobial activity against Escherichia coli and Salmonella. Among three AMPs, ANLP-K2 showed efficient antibacterial activity with 12 µM minimum inhibitory concentration (MIC). Slow degradation of ANLP-K1 (26.48%) and ANLP-K2 (13.21%) compared with linear ANLP (52.33%) at 480 min in serum stability assay indicates improved bio-stability of dimeric peptides. The AMPs presented no cytotoxicity in Vero cells. Dye penetration assays confirmed the membrane interacting nature of AMPs. The zeta potential analysis reveals effective charge neutralization of both lipopolysaccharide (LPS) and bacterial cells by dimeric AMPs. The dimeric AMPs on scanning electron microscopy studies showed multiple pore formations on the bacterial surface. Collectively, proposed Lysine scaffold dimerization of Apoptin NLS2 strategy resulted in enhancing antibacterial activity, bio-stability, and could be effective in neutralizing the off-target effect of LPS. In conclusion, these results suggest that nuclear localization sequence with a modified dimeric approach could represent a rich source of template for designing future antimicrobial peptides.

Multiple antigenic peptide-based flow through dot-blot assay for simultaneous antibody detection of infectious bronchitis virus and Newcastle disease virus

The present study describes the development of a novel affordable and rapid visual dot-blot assay using synthetic multiple antigenic peptides (MAP) for simultaneous detection of antibodies to infectious bronchitis virus (IBV) and Newcastle disease virus (NDV). Antibody detection efficiencies of MAP peptides namely, NP1 MAP (Nucleoprotein IBV) and HN MAP (Haemagglutinin-neuraminidase NDV) were studied in solid-phase indirect peptide ELISA. In comparison with the commercial kit, the NP1 MAP showed 89.20% diagnostic sensitivity (DSn) and 85.90% diagnostic specificity (DSp) at 19.45% ROC cut-off. Similarly, HN MAP was evaluated and showed 89.70% DSn and 92.90% DSp at 19.90 % ROC cut-off. The peptides after evaluating their ELISA performance were further used to device a flow-through dot-blot assay (FT-DBA) for simultaneous detection of IBV and NDV antibodies. The kappa value for IBV by FT-DBA in comparison to commercial ELISA was 0.64 whereas for NDV, FT-DBA gave a kappa value of 0.68 in comparison to commercial ELISA indicating substantial agreement between the assays. In essence, the divergent MAP based diagnostic design could provide an alternative for antibody detection of IBV and NDV. Further, the FT-DBA approach could be used for low cost, rapid and pen-side detection of IBV and NDV antibodies simultaneously.

Recent advances in the biodegradation of azo dyes

As dye demand continues to rapidly increase in the food, pharmaceutical, cosmetic, paper, textile, and leather industries, an industrialization increase is occurring. Meanwhile, the degradation and removal of azo dyes have raised broad concern regarding the hazards posed by these dyes to the ecological environment and human health. Physicochemical treatments have been applied but are hindered by high energy and economic costs, high sludge production, and chemicals handling. Comparatively, the bioremediation technique is an eco-friendly, removal-efficient, and cost-competitive method to resolve the problem. This paper provides scientific and technical information about recent advances in the biodegradation of azo dyes. It expands the biodegradation efficiency, characteristics, and mechanisms of various microorganisms containing bacteria, fungi, microalgae, and microbial consortia, which have been reported to biodegrade azo dyes. In addition, information about physicochemical factors affecting dye biodegradation has been compiled. Furthermore, this paper also sketches the recent development and characteristics of advanced bioreactors.