Expression of Toll-like receptors (TLR), in lymphoid organ of black tiger shrimp (Penaeus monodon) in response to Vibrio harveyi infection

The Toll-like receptors (TLR), being pattern recognition molecules, are a powerful first line of defense in response to pathogen invasion. They are known to play a crucial role in detecting and binding to the microbial molecule and triggering a non-specific immune response. Quantitative real time PCR (qPCR) expression of the TLR gene was studied in healthy and Vibrio harveyi infected black tiger shrimp (Penaeus monodon). Lymphoid tissue expression of TLR in V. harveyi infected animals 24 h post injection showed statistically significant up regulation of the gene as compared to the control animals sham injected with phosphate buffered saline (PBS). The qPCR expression pattern of TLR at different time points in shrimp administered with the immunostimulant glucan for 6 days by oral feeding followed by challenge with V. harveyi showed statistically significant level at 48 h post bacterial challenge as compared to the control (immunostimulant treated) animals sham injected with PBS. The novelty of the study is that it elicits the role of TLRs as important response proteins of the innate immune system in the shrimp

Comparative genomic insights into Yersinia hibernica – a commonly misidentified Yersinia enterocolitica-like organism

Food-associated outbreaks linked to enteropathogenic Yersinia enterocolitica are of concern to public health. Pigs and their meat are recognized risk factors for transmission of Y. enterocolitica. This study aimed to describe the comparative genomics of Y. enterocolitica along with a number of misclassified Yersinia isolates, now constituting the recently described Yersinia hibernica. The latter was originally cultured from an environmental sample taken at a pig slaughterhouse. Unique features were identified in the genome of Y. hibernica, including a novel integrative conjugative element (ICE), denoted as ICEYh-1 contained within a 255 kbp region of plasticity. In addition, a zebrafish embryo infection model was adapted and applied to assess the virulence potential among Yersinia isolates including Y. hibernica

Molecular Characterization of Antimicrobial Drug Resistant Escherichia coli Isolated from the Environment at Dakshina Kannada, Karnataka

Escherichia coli are commonly found in the gastrointestinal tract of humans and other warm-blooded organisms. Since E. coli can be discharge through deposition of fecal material, it has become habituated to soil and water in the environment. Hence the present study was undertaken to isolate and identify E. coli from various environments (viz., cattle waste, piggery, poultry and sewage water) and to determine their antibiogram patterns to different group of antimicrobial agents. A total of 120 samples comprising cattle wastes (30), poultry droppings (30), piggery (30), sewage water/sediment (30) were collected from the Dakshina Kannada and analyzed for the presence of E. coli. Of total samples screened, 82 (68.3%) were found to be positive to E. coli and among the 82 E. coli strains, 25 were isolated from cattle wastes, 18 from piggery, 13 from poultry and 26 from sewage samples. The antibiogram pattern of these strains showed varied multi-drug resistance profile to the selected antibiotics. Of 82 strains, 19 (23.2%) were susceptible to all the antibiotics and 63 were resistant to at least one of the drug tested. The results from present study revealed the higher relative resistance pattern to the tested antibiotic among E. coli suggesting their potentiality in transferring MDR thereby posing public health concerns in treating problems