Association of the extended-spectrum β-lactamase gene bla TLA-1with a novel ISCR element, ISCR20

Service de Bactériologie-Virologie, INSERM U914 Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Assistance Publique-Hôpitaux de Paris, Faculté de Médecine et Université Paris-Sud, Le Kremlin-Bicêtre, France.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.48). 09/2010; 54(9):4026-8. DOI: 10.1128/AAC.00075-10
Source: PubMed


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.

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Available from: Béatrice Berçot, Feb 10, 2014
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