conditional gene expression in mycobacterium abscessus条件在脓肿分枝杆菌基因表达.pdf

Conditional Gene Expression in Mycobacterium abscessus ´ 1,2 1,2 1,2{ 3 1,2 Melanie Cortes , Anil Kumar Singh , Jean-Marc Reyrat , Jean-Louis Gaillard , Xavier Nassif , Jean- Louis Herrmann3* ´ ´ ´ 1 Universite Paris Descartes, Faculte de medecine, Paris, France, 2 INSERM (U-1002), Paris, France, 3 EA 3647 Physiopathologie et diagnostic des infections microbiennes, ´ ˆ ´ Universite Versailles St Quentin, and Laboratoire de Microbiologie, Hopital Raymond Poincare, AP-HP, Garches, France Abstract Mycobacterium abscessus is an emerging human pathogen responsible for lung infections, skin and soft-tissue infections and disseminated infections in immunocompromised patients. It may exist either as a smooth (S) or rough (R) morphotype, the latter being associated with increased pathogenicity in various models. Genetic tools for homologous recombination and conditional gene expression are desperately needed to allow the study of M. abscessus virulence. However, descriptions of knock-out (KO) mutants in M. abscessus are rare, with only one KO mutant from an S strain described so far. Moreover, of the three major tools developed for homologous recombination in mycobacteria, only the one based on expression of phage recombinases is working. Several conditional gene expression tools have recently been engineered for Mycobacterium tuberculosis and Mycobacterium smegmatis, but none have been tested yet in M. abscessus. Based on previous experience with genetic tools allowing homologous recombination and their failure in M.