Genotypes and phenotypes of methicillin‐resistant staphylococci isolated from shrimp aquaculture farms

Abstract

Summary The population of methicillin‐resistant (MR) staphylococci in aquatic environment is rarely investigated. Here, we characterized a collection of MR staphylococci recovered from shrimp aquaculture farms (n = 37) in Kerala, India. A total of 261 samples yielded 47 MR isolates (16 S. aureus, 13 S. haemolyticus, 11 S. epidermidis, 3 S. saprophytics and 2 each of S.intermedius and S. kloosii). Multi‐drug resistance was evident in 72.3% of the isolates, with resistance mainly towards erythromycin (78.7%), norfloxacin and trimethoprim‐sulfamethoxazole (53.2%), and gentamicin (34%). Major resistance genes identified included mecA (100%), ermC (38.3%), aacA‐aphD (21.3%), tetK (14.9%) and tetM (21.3%). Almost 60% of the isolates carried type V SCCmec (Staphylococcal Cassette Chromosome mec), and the remaining harboured untypeable SCCmec elements. Comprehensive genotyping of the methicillin‐resistant Staphylococcus aureus isolates revealed high prevalence of ST772‐t345‐V (sequence type‐spa type‐SCCmec type) (75%), followed by minor representations of ST6657‐t345‐V and ST3190‐t12353. The isolates of S. haemolyticus and S. epidermidis were genotypically diverse as shown by their pulsed‐field gel electrophoresis (PFGE) profiles. Genes encoding staphylococcal enterotoxins were observed in 53.2% of the isolates. Various genes involved in adhesion and biofilm formation were also identified. In conclusion, our findings provide evidence that shrimp aquaculture settings can act as reservoirs of methicillin‐resistant staphylococci.

Facile Synthesis and Application of Ag-NPs for Controlling Antibiotic-ResistantPseudomonas spp. and Bacillus spp. in a Poultry Farm Environment

“…Te PCR confrmed bacterial species were subjected to determination of antibiotic resistance pattern phenotypically using 12 commercial antibiotics from diferent classes and groups such as gentamycin, ampicillin, cefxime, aztreonam, vancomycin, doxycycline, linezolid, erythromycin, chloramphenicol, trimethoprim, levofoxacin, and moxifoxacin following the disc difusion methods [127]. Bacillus spp.…”

Facile synthesis of CuONPs using Citrus limon juice for enhancing antibacterial activity against methicillin-resistant Staphylococcus aureus, beta-lactamase and tetracycline-resistant Escherichia coli

“…7a) indicates the presence of methicillin-resistant S. aureus , 47 as confirmed previously. 80,81 The amplified bands at 643 bp and 577 bp for blaTEM-1 (Fig. 7b) and tetA (Fig.…”

Molecular and Functional Characterization of a Short-Type Peptidoglycan Recognition Protein, Ct-PGRP-S1 in the Giant Triton Snail Charonia tritonis

“…We could speculate that in the process of aquaculture, they may be at risk of bacterial infection, especially the Vibrio, since there are many reports of bacterial infection causing a massive economic loss in the aquaculture industry [ 47 , 48 , 49 , 50 ]. Meanwhile, various aquatic animals have suffered from S. aureus infections [ 51 , 52 , 53 , 54 , 55 ]. In the present study, co-incubation assay revealed that recombinant Ct-PGRP-S1 was proven to have antibacterial activity against V. alginolyticus and S. aureus by direct contact, reflecting the importance of Ct-PGRP-S1 in the antibacterial defense of C. tritonis and providing important evidence to suggest that amidase-active PGRPs may function as the key effectors to promote antibacterial response in hosts.…”