Diversity and antibiotic resistance patterns of enterobacteria isolated from seafood in Thailand

Abstract

Contamination with enterobacteria was detectable in 89% of seafood samples from three central seafood markets in Thailand. The average numbers obtained from the same type of seafood were between 1.3 ± 0.9 and 4.5 ± 1.3 log CFU/g per sample. Eighty-one strains and 16 species were distinguished based on ERIC-PCR patterns and TP-RAPD patterns, respectively. The highest prevalence (90% of strains) was resistant to penicillin G whereas none was resistant to gentamycin. In addition, 63% exhibited multidrug resistance. The 16S rDNA sequences of a representative strain from each species exhibited 99% identity to either one of six genera including Citrobacter, Enterobacter, Klebsiella, Providencia, Serratia, and Yersinia. Three β-lactamase genes including blaTEM, ampC, and shv were detected at the frequencies of 43%, 27%, and 24%, respectively. The representative strains possessing β-lactamase genes exhibited β-lactamase activity ranging from 1.96 ± 0.88 to 11.3 ± 0.37 μmol of hydrolyzed nitrocefin/min/mg protein. Diversidad y patrones de resistencia a los antibióticos en enterobacterias aisladas de mariscos en Tailandia RESUMEN En 80% de las muestras de mariscos tomadas en tres mercados centrales de mariscos de Tailandia fue posible detectar contaminación por enterobacterias. Las mediciones promedio de enterobacterias obtenidas en el mismo tipo de marisco fluctúan entre 1.3 ± 0.9 y 4.5 ± 1.3 log cfu/g por muestra. A partir de patrones ERIC-PCR y TP-RAPD se distinguieron 81 cepas y 16 especies, respectivamente. Un porcentaje más elevado de las cepas (90%) es resistente a la penicilina G y ninguna de ellas es resistente a la gentamicina. Asimismo, 63% de las mismas exhibe resistencia a múltiples drogas. Las secuencias 16S ADNr de una cepa representativa de cada una de las especies exhibieron 99% de identidad con uno de seis géneros, incluyendo Citrobacter, Enterobacter, Klebsiella, Providencia, Serratia y Yersinia. Por otra parte, se detectaron tres genes de β-lactamasa, entre los que se incluyen blaTEM, ampC, y shv, con frecuencias de 43%, 27% y 24%, respectivamente. En las cepas representativas que poseen genes de β-lactamasa la actividad de esta enzimaoscila entre 1.96 ± 0.88 y 11.3 ± 0.37 μmol de proteína de nitrocefina/min/mg hidrolizada.

Antibiotic-Resistant Bacteria in Green Turtle (Chelonia mydas) Rearing Seawater

“…Conversely, evaluation of antibiotic resistance patterns in juvenile loggerhead turtles in North Carolina revealed very high susceptibility rates to gentamicin [ 32 ]. Moreover, a study of antibiotic-resistant patterns of enterobacteria from seafood in the central areas of Thailand, where the seafood was mostly caught from the upper Gulf of Thailand, has reported non-detected bacterial isolates resistant to gentamicin [ 33 ]. This implies very low resistance rates of bacteria to gentamicin in the coastal seawater of the Sattahip area, a part of the upper Gulf of Thailand.…”

Identification, Characterization, and Virulence Gene Expression of Marine Enterobacteria in the Upper Gulf of Thailand

“…The 59 enterobacterial strains (58.4%) exhibited seven antibiotic resistance gene patterns while the remaining 42 strains yielded negative results for the presence of all ten β-lactamase genes. These three antibiotic genes were the same as those detected in 81 enterobacterial strains isolated from seafood in Thailand in which the blaTEM , ampC , and blaSHV genes were detected at the frequencies of 43%, 27%, and 24%, respectively [ 84 ].…”

Distribution and expression of virulence genes in potentially pathogenic bacteria isolated from seafood in Thailand

“…As reported in our previous publication, 89% (31/35) of these seafood samples contained presumptive enterobacteria, as estimated by total plate counts using violet red bile glucose (VRBG) agar. The average numbers of presumptive enterobacteria per sample ranged between 1.3 ± 0.2 and 5.4 ± 0.1 log CFU/g (Pongsilp & Nimnoi, 2018). Forty-two presumptive isolates from three media were selected from different seafood species and collection sites.…”