Cloning and Nucleotide Sequence Analysis of the Ampicillin Resistance Gene on a Conjugative R Plasmid from the Fish PathogenPhotobacterium damselaesubsp.piscicida

Abstract

Abstract.-Transferable resistance to various drugs was investigated in strains of Photobacterium damselae subsp. piscicida from Japan. Drug resistance was transferred via two plasmids of 100 and 50 kilobases (kb) or three plasmids of 100, 50, and 40 kb. Resistance to ampicillin was transferred on the 50-kb plasmid. An ampicillin resistance gene in the 50-kb plasmid pPDP8517 from strain PP8517 was cloned from a 1.8-kb Hinc II fragment of the plasmid. The nucleotide sequence of the coding and flanking region of the ampicillin resistance gene was determined to be 1,736 base pairs. The nucleotide sequence identified an open reading frame (ORF) encoding 282 amino acid residues with a calculated molecular mass of 31,292 daltons. The ampicillin resistance gene's ORF was found to be a ␤-lactamase bearing low levels of amino acid identities (Ͻ63%) relative to other ␤-lactamases. This ORF was very high in amino acid identities with class A ␤-lactamases compared with those of class B, C, and D ␤-lactamases. Four important structural features were conserved in all class A ␤-lactamases present in the deduced amino acid sequence of the ampicillin resistance gene. These results suggest that the P. damselae subsp. piscicida ampicillin resistance gene is a class A ␤-lactamase encoded on an R plasmid that is distinctly different from other known ␤-lactamases. Moreover,

Interplay of a non-conjugative integrative element and a conjugative plasmid in the spread of antibiotic resistance via suicidal plasmid transfer from an aquaculture Vibrio isolate

“…Two hundred two CDSs (74.9%) showed similarity to the homologs from Vibrionaceae , and 178 CDSs (55.1%) showed relatively high similarity to the homologs from Vibrio nigripulchritudo , which is a new emerging shrimp pathogen (NC_010733) [ 23 ] ( S1 Dataset ). Fifteen CDSs showed similarity to the type IV secretion system components, and seven CDSs showed similarity to known ARGs, including tet (B), tet (M) [ 24 ], mef (C), mph (G) [ 25 ], sul 2 [ 26 ], catII [ 27 ], and a class A beta-lactamase gene [ 28 ], respectively. Except for catII , these ARGs were common to pAQU1 and pAQU1-like plasmids found in isolates at the same aquaculture site in Japan [ 4 , 11 ], and mef (C) and mph (G) have been identified in erythromycin-resistant isolates from an aquaculture site in Taiwan and a pig farm wastewater in Thailand [ 29 ].…”

Novel Conjugative Transferable Multiple Drug Resistance Plasmid pAQU1 from <i>Photobacterium damselae</i> subsp. <i>damselae</i> Isolated from Marine Aquaculture Environment

“…piscicida strains isolated from cultured yellowtail (33). CDS 084 encodes a 224 aminoacid protein that has the serine-threonine-phenylalanine-lysine (STFK) tetrad active site characteristic of serine beta-lactamases (21).…”

“…The phylogenetic relationship of this plasmid compared to other known groups of plasmids and integrative conjugative elements widely distributed among the species of Enterobacteriaceae and Vibrionaceae is discussed. Many reports have shown the prevalence of drug resistance among fish pathogens ( 6 , 24 , 33 ) and aquaculture environmental bacteria ( 15 , 38 ), whereas there is little information concerning the mechanism of their emergence. Our data provide useful insights into the molecular basis for the dissemination of drug resistance genes among bacteria in the aquaculture environment and their clinical impact.…”

Antimicrobial use in aquaculture re‐examined: its relevance to antimicrobial resistance and to animal and human health

“…A number of antimicrobial resistance genes appear to have been first detected in aquatic bacteria before being detected and disseminating among human and animal pathogens. These include some of the emerging plasmid‐mediated quinolone resistance (PMQR) genes found in aquatic Vibrio , Shewanella and Aeromonas (Table ) (Poirel et al ., 2005; 2012; Cattoir et al ., 2007; 2008; Xia et al ., ); new β‐lactamase genes from Photobacterium damselae (Table ) (Morii, ) and Oceanobacillus iheyensis (Toth et al ., ); a novel fosfomycin resistance determinant isolated from the aquatic environment (Xu et al ., 2011b); the widely disseminated emerging floR gene of human pathogens (Kim and Aoki, 1996a; Angulo, ; Arcangioli et al ., 1999; 2000; Bolton et al ., ; Cloeckaert et al ., 2000; 2001; Miranda and Rojas, ; Gordon et al ., ; Smith, 2008a,b; Cabello, ; Welch et al ., ; Fernández‐Alarcón et al ., ; Hall, ); and the chloramphenicol resistance genes catII , catB9 and catB2 from aquatic Photobacterium, Vibrio and Shewanella respectively (Roberts and Schwarz, ; Roberts et al ., ). Moreover, antimicrobial resistance gene variants including those for β‐lactams, aminoglycosides, tetracyclines, macrolides and heavy metals have been detected in the genome of the salmon pathogen Renibacteriun salmoninarum and the aquatic opportunistic human pathogen Stenotrophomonas maltophilia suggesting that these aquatic bacteria may be repositories for antimicrobial resistance genes (Crossman et al ., ; Wiens et al ., ).…”

“…Arcangioli et al (1999);Cloeckaert et al (2000);Gordon et al (2008);Smith (2008a,b);Cabello (2009);Welch et al (2009). j Morii (2004)Decousser et al (2001)…”