In silico epitope prediction and immunogenic analysis for penton base epitope-focused vaccine against hydropericardium syndrome in chicken.

Certain strains of fowl adenovirus serotype 4 (FAdV-4) of the family Adenoviridae are recognized to be the causative agents of Hydropericardium Syndrome (HPS) in broiler chicken. Despite the significantly spiking mortality in broilers due to HPS, not much effort has been made to design an effective vaccine against FAdV-4. The combination of immuno- and bioinformatics tools for immunogenic epitope prediction is the most recent concept of vaccine design. It reduces the time and effort required for hunting a potent vaccine candidate and is economical. Previously, we have reported the penton base protein of FAdV-4 to be a candidate for subunit vaccine against HPS. In the present study, we have computationally pre-screened promising B- and T-cell epitopes of the penton base. Multiple methods were employed for linear B-cell epitope identification; BepiPred and five other methods based on physicochemical properties of the amino acids. The penton base was homology modeled by means of Modeller 9.17 and after refinement of the model (by GalaxyRefine web server) ElliPro web tool was used to predict the discontinuous epitopes. NetMHCcons 1.1 and NetMHCIIpan 3.1 servers were used for the likelihood of peptide binding to Major Histocompatibility Complex (MHC) class I & II molecules respectively for T-cell epitope forecast. As a result, we identified the peptide stretch of 1-225  as the most promiscuous B- and T-cell epitope region in penton base Full Length (FL) protein sequence. Escherichia coli based expression vectors were generated containing cloned peptide stretch 1-225 (penton base1-225) and penton base FL gene sequence. The recombinant penton base1-225 and penton base FL proteins were expressed and purified using Escherichia coli-based expression system. Purification yield of penton base1-225 was 3-fold higher compared to penton base FL. These proteins were injected in chickens to determine their competence in protection against HPS. The results showed equal protection level of the two proteins and the commercial inactivated vaccine against FAdV-4 infection. The results suggest the peptide stretch 1-225 of penton base as a valuable candidate for developing an epitope-driven vaccine to combat HPS.

Synthesis, characterization, and antibacterial potential of silver nanoparticles synthesized from Coriandrum sativum L.

INTRODUCTION: Nanoparticles (NPs) have become very important owing to their various uses. In this research, an environmentally friendly biological technique was used to synthesize silver nanoparticles with Coriandrum sativum L. The objective of this research to use the source for the fabrication of silver NPs from C. sativum L., and to check the activity of the fabricated silver NPs was determined versus a couple of gram negative and a couple of gram positive bacteria in the presence of antibiotic viz. gentamicin to judge their impact. METHODOLOGY: A silver nitrate solution, which served as the reducing and capping agent, was mingled with coriander leaf extract. The solution's temperature and pH were maintained at 75°C and 8.6, respectively. The observed mean particle size (z-average) and polydispersity index were 390.2nm and 0.452, respectively. The synthesized Ag NPs were characterized using different techniques, including scanning electron microscopy (SEM), X-ray diffraction, and Fourier transmission infrared (FTIR) analysis. The globular shape of the silver nanoparticles was depicted in SEM illustrations. RESULTS: XRD data revealed the mean size of the particles was 11.9nm. The FTIR analysis showed the existence of various functional groups, including CO and OH. When their antibacterial ability was tested, it was found that the fabricated Ag NPs inhibited Bacillus subtilis, Pasteurella multocida, Enterobacter aerogenes, and Staphylococcus aureus, with a greater effect against B. subtilis and P. multocida compared to E. aerogenes and S. aureus. CONCLUSION: It has been concluded small silver NPs benefited from a higher surface area ratio, as shown by the results of experiments where smaller particles had a better bactericidal proficiency than large silver-based NPs. Silver-based NPs infiltrate bacterial cells, as well as interfere with their exterior membrane. Silver ions also have the potential to interact with bacterial DNA, inhibiting the reproductive system of the cell.