Diversion of phagosome trafficking by pathogenic Rhodococcus equi depends on mycolic acid chain length.
Cell Microbiol
; 15(3): 458-73, 2013 Mar.
Article
em En
| MEDLINE
| ID: mdl-23078612
ABSTRACT
Rhodococcus equi is a close relative of Mycobacterium spp. and a facultative intracellular pathogen which arrests phagosome maturation in macrophages before the late endocytic stage. We have screened a transposon mutant library of R. equi for mutants with decreased capability to prevent phagolysosome formation. This screen yielded a mutant in the gene for ß-ketoacyl-(acyl carrier protein)-synthase A (KasA), a key enzyme of the long-chain mycolic acid synthesizing FAS-II system. The longest kasA mutant mycolic acid chains were 10 carbon units shorter than those of wild-type bacteria. Coating of non-pathogenic E. coli with purified wild-type trehalose dimycolate reduced phagolysosome formation substantially which was not the case with shorter kasA mutant-derived trehalose dimycolate. The mutant was moderately attenuated in macrophages and in a mouse infection model, but was fully cytotoxic.Whereas loss of KasA is lethal in mycobacteria, R. equi kasA mutant multiplication in broth was normal proving that long-chain mycolic acid compounds are not necessarily required for cellular integrity and viability of the bacteria that typically produce them. This study demonstrates a central role of mycolic acid chain length in diversion of trafficking by R. equi.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fagossomos
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Rhodococcus equi
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Interações Hospedeiro-Patógeno
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Macrófagos
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Ácidos Micólicos
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article