Introduction and objective: The aims of this study were to search for the presence of bacteria in sea snails (Rapana venosa) by using culturomics and Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and the antibiotic resistance/susceptibility of the sea snails.
Material and methods: The anti-microbial susceptibilities of Gram-negative bacteriawas assessed by the Kirby-Bauer disk diffusion method, the presence of the mcr genes (mcr-1 to -5), the major carbapenemase and β-lactamase resistant genes in Gram-negative bacteria, using mPCR method and 16S rRNA sequence analysis of A. hydrophila isolates.
Results: Bacterial growth accounted for 100% and 94.2% in the samples of intestine and meat, respectively, in the snails. The main organisms identified by MALDI-TOF MS were A. salmonicida subsp. salmonicida at 33.7%, followed by Raoultella ornithinolytica at 9.6% (10/104) and Staphylococcus warneri at 7.7% in meat and intestine samples. Aeromonas hydrophila/punctata (caviae), Aeromonas sobria, Klebsiella aerogenes, Klebsiella oxytoca, Raoultella planticola, Shewanella putrefaciens and Vibrio vulnificus are intrinsic or chromosomally-mediated resistant against ampicillin. No mcr genes (mcr-1 to -5), the major carbapenemase and β-lactamase resistant genes were found. Aeromonas salmonicida subsp. salmonicida showed very low levofloxacin and meropenem resistance levels at 2.9%. When the sequence was searched in the Blast database, the genome of A. hydrophila/punctata (caviae) isolate showed high similarity with the A. hydrophila sequences.
Conclusions: Conclusions. The findings obtained not only provide data about the proportion of bacteria in the gut and meat of the sea snails and their antibiotic resistance/susceptibility, but also show the absence of carbapenemase, colistin, and β-lactamase resistant genes among bacterial isolates from sea snail gut microbes.
Keywords: Carbapenem; MALDI-TOF MS; colistin; resistance genes; sea snail.