Association of the extended-spectrum beta-lactamase gene blaTLA-1 with a novel ISCR element, ISCR20.
ABSTRACT The bla(TLA-1) gene encoding an extended-spectrum beta-lactamase was identified in 11 enterobacterial isolates from Mexico City, Mexico. This gene was located on different plasmids and plasmid types with different sizes and incompatibility groups. It was associated with a novel insertion sequence, ISCR20, encoding a putative transposase that shared only 20% amino acid identity with the most closely related transposase of ISCR1. The ISCR20 element provided specific promoter sequences for expression of the bla(TLA-1) gene.
Full-textDOI: · Available from: Béatrice Berçot, Feb 10, 2014
SourceAvailable from: María Guadalupe Miranda-Novales[Show abstract] [Hide abstract]
ABSTRACT: To determine the frequency of the gene qacEdelta1 and characterize the resistance to biocides of extended-spectrum beta-lactamases producing enterobacteriaceae (ESBL-PE) obtained from clinical isolates causing nosocomial infections. In total 59 ESBL-PE causing nosocomial infections were included: Klebsiella pneumoniae (35) and Enterobacter cloacae (24). Minimal inhibitory concentration (MIC) was tested for chlorhexidine (CHX) and benzalkonium chloride (CLBZ) by agar dilution technique. Amplification of the SHV, TLA-1 and qacEdelta1 genes were performed by PCR using specific primers and plasmid identification was done by alkaline lysis method. Matting experiments were obtained on solid agar method. Chlorhexidine-resistance was found in 100% of the ESBL-PE and benzalkonium chloride-resistance in 80%. In 68% of the biocides-resistant strains the qacEdelta1 gene was present. The 66% of resulting transconjugants were resistant to CHX and the gene qacEdelta1 was detected in 55%. The qacEdelta1 gene of antiseptic resistance is widespread in the EP-ESBL and can be transferred horizontally. Thus it is advisable to use combinations of antiseptics, as recommended in the literature, to avoid selection of multiresistant bacteria in hospitals, causing nosocomial infections.Revista de investigacion clinica; organo del Hospital de Enfermedades de la Nutricion 64(6 Pt 1):535-40. · 0.31 Impact Factor
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ABSTRACT: Introduction: Bacterial resistance to antibiotics is a worldwide public health concern. Research priorities for the study and control of this emerging problem include country-wide surveillance. Objective: To review and comment on the contributions by Mexican investigators towards a greater understanding of the mechanisms of bacterial antibiotic resistance. Materials and methods: A comprehensive search of the medical literature on Medline/PubMed between 1973 and July 2013 was performed. Results: The contributions of Mexican investigators have included descriptions of resistance in enteric pathogens, such as Salmonella Typhi, publications on the production of extended spectrum beta-lactamases, metallo-beta-lactamases, and carbapenemases, resistance mechanisms of Pseudomonas aeruginosa , and the evolution of resistance in Gram-positive pathogens, including Streptococcus pneumoniae , Staphylococcus aureus , and Enterococcus spp. Conclusion: The Mexican literature on mechanisms of bacterial resistance is relevant for the development of plans to control the antibiotic resistance crisis.Biomédica: revista del Instituto Nacional de Salud 04/2014; 34(Suppl 1):181-190. DOI:10.1590/S0120-41572014000500021 · 0.62 Impact Factor
Biomédica: revista del Instituto Nacional de Salud 08/2013; 34:181. DOI:10.7705/biomedica.v34i0.2142 · 0.62 Impact Factor