Differential fadE28 expression associated with phenotypic virulence of Mycobacterium tuberculosis

T. H.J. Lam, K. Y. Yuen, P. L. Ho, K. C. Wong, W. M. Leong, Ka Wai Helen Law, X. H. Weng, W. H. Zhang, S. Chen, W. C. Yam

Research output: Journal article publicationJournal articleAcademic researchpeer-review

11 Citations (Scopus)

Abstract

Ability to persist in human macrophages is central to the virulence of Mycobacterium tuberculosis and is not invariable among various strains. Differential gene expression that is associated with phenotypic virulence may provide additional information of virulent genes involved in the pathogenesis of M. tuberculosis, which is not fully elucidated. Three hypervirulent strains of M. tuberculosis isolated from patients suffering with tuberculous meningitis were shown to grow more rapidly inside human macrophages in a previous study. In the current investigation, expression of 7 mycobacterial genes (fadE28, mce1A, mymA, acr, sigA, sugC, and Rv3723) of these strains during ex vivo macrophage challenge and in vitro acid shock was quantified by real-time PCR. Using rrs gene as a normalisation gene, fadE28 gene exhibited differential gene expression that is associated with phenotypic virulence, whereas the other 6 genes showed indistinguishable expression patterns. Up-regulation of fadE28 gene in the hypervirulent strains may account for virulence by increasing the efficiency of beta-oxidation, which is important for the persistence in macrophages as M. tuberculosis uses fatty acids preferably inside phagosome of macrophages. The fadE28 gene, together with its adjacent genes may also be critical in the process of lipid modification that could facilitate parasitism in human macrophages.
Original languageEnglish
Pages (from-to)12-17
Number of pages6
JournalMicrobial Pathogenesis
Volume45
Issue number1
DOIs
Publication statusPublished - 1 Jul 2008
Externally publishedYes

Keywords

  • Differential gene expression
  • fadE28
  • Hypervirulent strain
  • Mycobacterium tuberculosis

ASJC Scopus subject areas

  • Microbiology
  • Infectious Diseases

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