Mobile class A β-lactamase gene .

Despite increasing reports, class A β-lactamases of environmental bacteria remain very poorly characterized, with limited understanding of their transmission patterns. To address this knowledge gap, we focused on a recently designated GMA family β-lactamase gene, , found in marine bacterial genera such as . This study shows that gammaproteobacterial mobile class A β-lactamase is specialized for penicillin degradation, and is frequently linked to strand-biased circularizing integrative elements (SEs) in sequences in the RefSeq/GenBank database.

Retrospective identification of pathogenic mycobacterial species in fish: YM-3, isolated from a yellowtail fish in 1986 in Kochi, Japan.

The complete genome sequence of mycobacterial strain YM-3, isolated from cultured yellowtail in 1986, was determined. The strain was , a closely related subspecies of , so the strain was isolated earlier than the first report of the subspecies in 2005.

Host range of strand-biased circularizing integrative elements: a new class of mobile DNA elements nesting in Gammaproteobacteria.

Background: The strand-biased circularizing integrative elements (SEs) are putatively non-mobilizable integrative elements for transmitting antimicrobial resistance genes. The transposition mode and the prevalence of SEs in prokaryotes remain vague.

Results: To corroborate the transposition mode and the prevalence of SEs, hypothetical transposition intermediates of an SE were searched for in genomic DNA fractions of an SE host.

Atypical integrative element with strand-biased circularization activity assists interspecies antimicrobial resistance gene transfer from Vibrio alfacsensis.

The exchange of antimicrobial resistance (AMR) genes between aquaculture and terrestrial microbial populations has emerged as a serious public health concern. However, the nature of the mobile genetic elements in marine bacteria is poorly documented. To gain insight into the genetic mechanisms underlying AMR gene transfer from marine bacteria, we mated a multidrug-resistant Vibrio alfacsensis strain with an Escherichia coli strain, and then determined the complete genome sequences of the donor and the transconjugant strains.

Genetic Environment Surrounding in Clinical Isolates of Shewanella algae Clade and Enhanced Expression of in a Carbapenem-Resistant Isolate.

Although spp. are most frequently isolated from marine environments; more rarely, they have been implicated in human infections. spp.

Characterization of Prototheca CYP51/ERG11 as a possible target for therapeutic drugs.

Unlabelled: Prototheca spp. are achlorophyllous algae, ubiquitous in nature. An increasing number of human and animal cases of Prototheca infection (protothecosis) are reported, and antifungal azoles, which inhibit sterol 14α-demethylase (CYP51/ERG11) involved in ergosterol biosynthesis, have empirically been used for the treatment of protothecosis.

Development of biliary stent applying the antibacterial activity of silver: A literature review.

Background: Endoscopic transpapillary stenting is commonly performed in patients with obstructive jaundice caused by a biliary stricture. Although the plastic stent (PS) is widely used for biliary drainage because of the low-cost and easy procedure, patency is short after placement in the bile duct because of the small diameter. Dysfunction of PS is primarily caused by biliary sludge that forms as a result of bacterial adhesion and subsequent biofilm formation on the inner surface of the stent.

The novel mef(C)-mph(G) macrolide resistance genes are conveyed in the environment on various vectors.

Background: The novel tandem genes mef(C) and mph(G) have been reported in marine bacteria in Japan. This paper aimed to characterise the extent of environmental distribution of mef(C) and mph(G) as well as their dissemination and persistence in aquatic bacterial communities.

Methods: Erythromycin-resistant bacteria were isolated from Japan, Taiwan and Thailand aquaculture sites.

Various pAQU plasmids possibly contribute to disseminate tetracycline resistance gene tet(M) among marine bacterial community.

Emergence of antibiotic-resistant bacteria in the aquaculture environment is a significant problem for disease control of cultured fish as well as in human public health. Conjugative mobile genetic elements (MGEs) are involved in dissemination of antibiotic resistance genes (ARGs) among marine bacteria. In the present study, we first designed a PCR targeting traI gene encoding essential relaxase for conjugation.

Novel conjugative transferable multiple drug resistance plasmid pAQU1 from Photobacterium damselae subsp. damselae isolated from marine aquaculture environment.

The emergence of drug-resistant bacteria is a severe problem in aquaculture. The ability of drug resistance genes to transfer from a bacterial cell to another is thought to be responsible for the wide dissemination of these genes in the aquaculture environment; however, little is known about the gene transfer mechanisms in marine bacteria. In this study, we show that a tetracycline-resistant strain of Photobacterium damselae subsp.

Differences of genetic diversity and antibiotics susceptibility of Pseudomonas aeruginosa isolated from hospital, river and coastal seawater.

Pseudomonas aeruginosa is an opportunistic pathogen, and ubiquitously found in natural environments. However, details on difference between clinical and environmental isolates have not been reported enough. In this study, we defined existence of marine specific genogroup and different drug susceptibility among isolates from clinical, river and coastal seawaters.

Occurrence of two genotypes of tetracycline (TC) resistance gene tet(M) in the TC-resistant bacteria in marine sediments of Japan.

The tetracycline (TC) resistance gene tet(M) was monitored in bacteria isolated from Japanese coastal and off-shore marine sediments. The high rate of occurrence of TC resistant (TC(r)) bacteria (120 microg mL(-1) TC) was observed at frequency ranges between 0.0-0.

Detection of the sul1, sul2, and sul3 genes in sulfonamide-resistant bacteria from wastewater and shrimp ponds of north Vietnam.

To assess the presence and distribution of the sul genes (sul1, sul2, and sul3) and plasmids in human-mediated environments of north Vietnam, we examined a total of 127 sulfonamide-resistant (SR) bacterial isolates from four shrimp ponds (HNAQs), a city canal (HNCs) and three fish ponds that received wastewater directly from swine farms (HNPs). Results from the SR isolates revealed that sul genes were most frequently detected in the HNPs (92.0%), followed by HNCs (72.

Molecular evidence for the ancient origin of the ribosomal protection protein that mediates tetracycline resistance in bacteria.

The ribosomal protection proteins (RPPs) mediate the resistance to tetracycline (TC) in Gram-positive and Gram-negative bacteria. The RPPs display sequence similarity to translation elongation factors, EF-G/EF-2 and EF-Tu/EF-1alpha. To determine the evolutionary origin of the RPPs, we constructed a composite phylogenetic tree of the RPPs, EF-G/EF-2 and EF-Tu/EF-1alpha.

The diversity of multi-drug resistance profiles in tetracycline-resistant Vibrio species isolated from coastal sediments and seawater.

In this study we examined the multi-drug resistance profiles of the tetracycline (TC) resistant genus Vibrio to determine its susceptibility to two beta-lactams, ampicillin (ABPC), and mecillinam (MPC), as well as to macrolide, erythromycin (EM). The results showed various patterns of resistance among strains that were isolated from very close geographical areas during the same year, suggesting diverse patterns of drug resistance in environmental bacteria from this area. In addition, the cross-resistance patterns suggested that the resistance determinants among Vibrio spp.

Degradation of tributyltin in microcosm using Mekong River sediment.

The degradation of tributyltin (TBT) and changes of bacterial number and community structures were investigated in microcosms using the sediment collected from the Mekong River, Vietnam. Concentrations of TBT in sediments were less than 0.62 ng/g (dry wt), lower than those reported from other areas.

16S rRNA mutations that confer tetracycline resistance in Helicobacter pylori decrease drug binding in Escherichia coli ribosomes.

Tetracycline resistance in clinical isolates of Helicobacter pylori has been associated with nucleotide substitutions at positions 965 to 967 in the 16S rRNA. We constructed mutants which had different sequences at 965 to 967 in the 16S rRNA gene present on a multicopy plasmid in Escherichia coli strain TA527, in which all seven rrn genes were deleted. The MICs for tetracycline of all mutants having single, double, or triple substitutions at the 965 to 967 region that were previously found in highly resistant H.

Incidence of antibiotic resistance in Campylobacter jejuni isolated in Alberta, Canada, from 1999 to 2002, with special reference to tet(O)-mediated tetracycline resistance.

Of 203 human clinical isolates of Campylobacter jejuni from Alberta, Canada (1999 to 2002), 101 isolates (50%) were resistant to at least 64 microg of tetracycline/ml, with four isolates exhibiting higher levels of tetracycline resistance (512 microg/ml). In total, the MICs for 37% of tetracycline-resistant isolates (256 to 512 microg/ml) were higher than those previously reported in C. jejuni (64 to 128 microg/ml).

Occurrence of tetracycline resistance genes tet(M) and tet(S) in bacteria from marine aquaculture sites.

Occurrence of tetracycline resistance genes encoding ribosomal protection proteins was examined in 151 tetracycline-resistant bacterial isolates from fish and seawater at coastal aquaculture sites in Japan and Korea. The tet(M) gene was detected in 34 Japanese and Korean isolates, which included Vibrio sp., Lactococcus garvieae, Photobacterium damsela subsp.

New Mg2+-dependent oxytetracycline resistance determinant tet 34 in Vibrio isolates from marine fish intestinal contents.

A new oxytetracycline (OTC) resistance (Otc(r)) determinant, Tet 34, was cloned from chromosomal DNA of Vibrio sp. no. 6 isolated from intestinal contents of cultured yellowtail (Seriola quinqueradiata).