Genomic basis of antibiotic resistance in Vibrio parahaemolyticus strain JPA1

A multi-resistant strain of Vibrio parahaemolyticus was isolated from a tropical estuary in Rio de Janeiro, Brazil. Genome sequencing was conducted to establish the molecular basis of antibiotic resistance in this organism. The genetic content of this strain revealed it to be a non-virulent lineage that nevertheless possesses several antibiotic resistance determinants.

RAW TROPICAL OYSTERS AS VEHICLES FOR MULTIDRUG-RESISTANT Vibrio parahaemolyticus / Ostras tropicais cruas como fonte de Vibrio parahaemolyticus multirresistentes

The following study aimed to determine the antimicrobial susceptibility profile of Vibrio parahaemolyticus strains from fresh and frozen oysters Crassostrea rhizophorae sold in Fortaleza-Brazil. An antibiogram was performed on 87 isolates using nine antibiotics: gentamicin (Gen 10 µg), ampicillin (Amp 10 µg), penicillin G (Pen 10U), ciprofloxacin (Cip 5 µg), chloramphenicol (Chl 30 µg), nalidixic acid (Nal 30 µg), tetracycline (Tet 30 µg), vancomycin (Van 30 µg) and erythromycin (Ery 15 µg). All strains were resistant to at least one antibiotic, and 85 (97.7%) were multi-resistant, with predominance of the Van+ Pen+Amp resistance profile (n = 46). Plasmid resistance to Pen, Amp and Ery was detected. Thus, the risk that raw oyster consumption poses to the health of consumers is highlighted, due to the fact that these bivalves may host antibacterial-resistant microorganisms.

O presente estudo objetivou determinar o perfil de suscetibilidade a antimicrobianos de cepas de Vibrio parahaemolyticus oriundas de ostras “in natura” e congeladas comercializadas em Fortaleza-Brasil. Oitenta e sete (87) cepas foram submetidas ao antibiograma com emprego de nove antibióticos: gentamicina (Gen 10 µg), ampicilina (Amp 10 µg), penicilina G (Pen 10U), ciprofloxacin (Cip 5 µg), cloranfenicol (Clo 30 µg), ácido nalidíxico (Nal 30 µg), tetraciclina (Tet 30 µg), vancomicina (Van 30 µg) e eritromicina (Eri 15 µg). Todas as cepas mostram-se resistentes a pelo menos um antibiótico, e 85 (97,7%) apresentaram multirresistência, com predomínio do perfil Van+ Pen+Amp (n = 46). Foi detectada resistência plasmidial a Pen, Amp e Eri. Dessa forma, o risco que o consumo de ostras cruas representa para a saúde dos consumidores merece ser destacado, uma vez que esses bivalves podem ser veículos de transmissão de micro organismos multirresistentes a fármacos antibacterianos.

Characterization of Vibrio Parahaemolyticus isolated from oysters and mussels in São Paulo, Brazil / Caracterização de Vibrio parahaemolyticus isolados de ostras e mexilhões em São Paulo, Brasil

Vibrio parahaemolyticus is a marine bacterium, responsible for gastroenteritis in humans. Most of the clinical isolates produce thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) encoded by tdh and trh genes respectively. In this study, twenty-three V. parahaemolyticus, previously isolated from oysters and mussels were analyzed by PCR using specific primers for the 16S rRNA and virulence genes (tdh, trh and tlh) and for resistance to different classes of antibiotics and PFGE. Nineteen isolates were confirmed by PCR as V. parahaemolyticus. The tlh gene was present in 100 percent of isolates, the tdh gene was identified in two (10.5 percent) isolates, whereas the gene trh was not detected. Each isolate was resistant to at least one of the nine antimicrobials tested. Additionally, all isolates possessed the blaTEM-116 gene. The presence of this gene in V. parahaemolyticus indicates the possibility of spreading this gene in the environment. Atypical strains of V. parahaemolyticus were also detected in this study.

Vibrio parahaemolyticus é uma bactéria marinha, responsável por gastroenterite em humanos. A maioria dos isolados clínicos produzem hemolisina termoestável direta (TDH) e hemolisina TDH-relacionada (TRH) codificadas por genes tdh e trh, respectivamente. Neste estudo, vinte e três V. parahaemolyticus, previamente isolados de ostras e mexilhões foram analisados por PCR utilizando indicadores específicos para o gene 16S rRNA, genes de virulência (tdh, trh e tlh), resistência a diferentes classes de antibióticos, e PFGE. Dezenove isolados foram confirmados por PCR, como V. parahaemolyticus. O gene tlh estava presente em 100 por cento dos isolados, o gene tdh foi identificado em dois (10,5 por cento) dos isolados, enquanto que o gene trh não foi detectado. Cada isolado foi resistente a pelo menos um dos nove antibióticos testados. Além disso, todos os isolados apresentaram resultado positivo para o gene blaTEM-116. A presença deste gene em V. parahaemolyticus indica a possibilidade de propagação desse gene no ambiente. Cepas atípicas de V. parahaemolyticus foram também detectadas neste estudo.

[Effect of Zataria multiflora Boiss. essential oil on the behavior of Vibrio parahaemolyticus in salted fish]

Thyme [Zataria multiflora Boiss.] is one of the Iranian traditional spices and it has antimicrobial effect on the pathogenic bacteria which are agents for some current food borne intoxications. The aim of this study was to evaluate the antimicrobial activity of Zataria multiflora Boiss. essential oil on V. parahaemolyticus in salted [8% Nacl in tissue] silver carp. Effect of different concentrations of this Essential oil [0.0%, 0.045%, 0.135%, 0.405%, 0.810%] on behavior of V. parahaemolyticus in two temperatures [15, 25 C] was determined by evaluation of the bacterial growth in salted fish fillets. The essential oil in used concentrations had significant inhibitory effect on the growth of V. parahaemolyticus in salted fish compare with control treatment during the storage time [p<0.05]. There was no significant difference between all treatments. The results showed that Zataria multiflora Boiss. Essential oil had inhibitory effect on V. parahaemolyticus, therefore it can be considered as a natural preservative in salted fish

Detection of tdh and trh genes in Vibrio parahaemolyticus isolated from Corbicula moltkiana prime in West Sumatera, Indonesia.

The occurrence of Vibrio parahaemolyticus in raw Corbicula moltkiana Prime from Lake Singkarak and Pasar Raya Padang market and in cooked samples in West Sumatera, Indonesia, was studied. Thirteen raw and seven cooked bivalve samples were positive using CHROMAgar Vibrio medium. All 47 V parahaemolyticus isolates were positive for toxR gene but negative for trh. However, 36% (17/47) of V parahaemolyticus strains were positive for tdh gene. Antibiotic profiling showed that 76% and 38% of isolates from raw and cooked bivalves respectively were resistant to ampicillin. Using RAPD-PCR analysis, most of the strains were clustered according to their source of isolation but some of the strains from raw and cooked samples were clustered together. These results indicate that pathogenic V parahaemolyticus isolates are present in Corbicula moltkiana Prime in West Sumatera, Indonesia, suggesting that V parahaemolyticus may also be present in seafood in other regions of Indonesia.