Abstract
The increase of antimicrobial resistant strains is leading to an emerging threat to public health. Pathogenic Vibrio are responsible for human and animal illness. The Enterobacteriaceae family includes microorganisms that affect humans, causing several infections. One of the main causes of human infection is related to the ingestion of undercooked seafood. Due to their filter-feeding habit, marine invertebrates, such as clams, are known to be a natural reservoir of specific microbial communities. In the present study, Vibrionaceae and coliforms microorganisms were isolated from clams. A microbial susceptibility test was performed using the disk diffusion method. From 43 presumptive Vibrio spp. and 17 coliforms, three Vibrio spp. with MICs to colistin >512 mg L−1 were found. From the 23 antimicrobial resistance genes investigated, only the three isolates that showed phenotypic resistance to colistin contained the mcr-1 gene. Genotypic analysis for virulence genes in EB07V indicated chiA gene presence. The results from the plasmid cure and transformation showed that the resistance is chromosomally mediated. Biochemical analysis and MLSA, on the basis of four protein-coding gene sequences (recA, rpoB, groEL and dnaJ), grouped the isolates into the genus Vibrio but distinguished them as different from any known Vibrio spp.
Highlights
Accepted: 3 February 2022The genus Vibrio contains more than 130 species [1,2] and includes both non-pathogenic and pathogenic species, being highly genetically diverse [3,4]
The Colony-Forming Units (CFUs) per g of molluscs, of Vibrio spp. and coliforms were determined for each clam species isolated at different locations
When attempting to cure the isolates, no differences were observed when the number of growing colonies in medium Mueller-Hinton agar (MHA) with and without colistin were compared (Figure S1). These results indicate that the observed resistance to colistin in all three isolates is chromosomally mediated
Summary
Accepted: 3 February 2022The genus Vibrio contains more than 130 species [1,2] and includes both non-pathogenic and pathogenic species, being highly genetically diverse [3,4]. Non-pathogenic Vibrio, on the other hand, are not associated with human illnesses, and are, not routinely identified [9] These so-called “marine species” or “marine vibrios”, have been frequently isolated, receiving more attention in recent years since they have an important role in specific ecological niches and belong to autochthonous marine microbial communities [4]. These niches are often fish farms, where antibiotics are frequently used, and Vibrio can become reservoirs of antimicrobial resistance genes [10,11]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call