Novel in-genome based analysis demonstrates the evolution of OmpK37, antimicrobial resistance gene from a potentially pathogenic pandrug resistant Klebsiella pneumoniae MS1 isolated from healthy broiler feces.

Antimicrobial resistance transmission from farm animals to humans is a critical health concern and hence a detailed molecular surveillance is essential for tracking the spread and consequent evolution of antimicrobial resistance. In this study, a pan-drug resistant Klebsiella pneumoniae MS1 strain was isolated from a healthy broiler farm and studied. From the results of the study, MS1 was found to be is resistant to 18 tested antibiotics and has a high-risk to be pathogenic to humans with a probability of 0.80. The whole genome sequencing data of MS1 was used to predict the presence of antimicrobial resistance genes and pathogenicity. The genome analysis has revealed MS1 to have 34 AMR genes. Out of these, the AMR gene OmpK37 codes for an important protein involved in cell permeability and hence in antibiotic resistance. Further analysis was carried out by using an in-genome analysis method to understand the evolution of OmpK37 and the underlying reason for the emergence of resistance. From the detailed analysis, the current study could demonstrate for the first time the evolution of OmpK37 from OmpC. Though structurally OmpK37 was very similar to other porins present in MS1, it was found to have higher mutability as a distinguishing feature which makes it an important protein in monitoring the evolving resistances in microorganisms.

Predicting Human Risk with Multidrug Resistant Enterobacter hormaechei MS2 having MCR 9 Gene Isolated from the Feces of Healthy Broiler Through Whole-Genome Sequence-Based Analysis.

The zoonotic spread of antimicrobial resistance (AMR) and the associated infections are becoming a major threat to the human population worldwide. Strategies to identify the potential pathogen dissemination by seemingly healthy livestock are at a nascent stage and it is of significant importance to monitor environmental evolution of AMR. In this study, a multidrug resistant strain (MDR) of Enterobacter hormaechei MS2 isolated from the feces of healthy broiler chicken has been characterized by whole-genome sequencing-based method. Here, the isolate was primarily subjected to antimicrobial susceptibility testing followed genome sequencing and analysis. From the antimicrobial susceptibility testing result, the strain was found to be resistant to multiple classes of drugs including the colistin which is an important  last resort drug used to treat infectious diseases. The resistome prediction of genomic data further revealed the presence of 7 perfect and 26 strict hits including those for MCR-9 and FosA2. The pathogenicity prediction has also demonstrated the strain to have the potential to be a human pathogen with 0.72 probability. The phylogenetic analysis has also supported the zoonotic potential of the strain due to its clustering with isolates from both human and livestock-associated host groups. The results of the study suggest the need for a strong surveillance system to identify the opportunistic zoonotic pathogens to prevent a silent AMR menace mediated by them. Carriage of multi-drug resistant strains in the livestock gut microbiome is also a serious concern as it has high AMR transmissibility through contact and supply chain activities.

Biofilm and Biocontrol Modulation of Paenibacillus sp. CCB36 by Supplementation with Zinc Oxide Nanoparticles and Chitosan Nanoparticles.

Endophytic bacteria with multi-trait plant beneficial features have applications to enhance agricultural productivity by supporting the plant growth, yield, and disease resistance. In this study, Paenibacillus sp. CCB36 was isolated from the rhizome of Curcuma caesia Roxb., and its biofilm formation and antifungal properties have been evaluated in the presence of nanoparticles. Chitosan nanoparticles (CNPs) were synthesized and characterized by UV-visible spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, high-resolution-transmission electron microscopic (HR-TEM) analysis, scanning electron microscopic (SEM) analysis, and dynamic light scattering (DLS). The effect of zinc oxide nanoparticles (ZnONPs) and CNPs on biofilm formation of Paenibacillus sp. CCB36 was evaluated by tissue culture plate assay. ZnONPs reduced its biofilm formation and was found to get modulated in the presence of CNPs as revealed by atomic force microscopy (AFM). Hence, CNPs were selected for further studies. Interestingly, biocontrol property of Paenibacillus sp. CCB36 against Rhizoctonia solani was also found to get enhanced when supplemented with chitosan nanoparticles. The results of the study indicate application of nanoparticles to improve colonization and active functioning of endophytic bacteria which can have significant application in agriculture.

Application of novel zinc oxide reinforced xanthan gum hybrid system for edible coatings.

Zinc oxide (ZnO) encapsulated xanthan-based edible coating has been demonstrated in this paper for its main attribute of displaying superior anti-bacterial properties. The fabrication of microparticles was carried out through emulsion solvent evaporation route where ZnO particles get adsorbed onto xanthan gum matrix. Morphological analysis through TEM showed a flower like appearance for ZnO and core-shell morphology was observed for the hybrid system. The FT-IR analysis showed the successful encapsulation of ZnO into xanthan. To ensure the developed materials to be harmless for fruits and vegetables, the biocompatibility studies such as toxicity assay and blood compatibility studies were carried out. The results established that the hybrid microparticles were compatible to the blood cells and featured excellent cell viability upon treatment with human fibroblast cells. Finally a significant finding of this biocompatible hybrid coating on apples and tomatoes was the negligible weight loss for both in comparison to their uncoated fruits and vegetables under ambient conditions.