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Analysis of expression profile of mce operon genes (mce1, mce2, mce3 operon) in different Mycobacterium tuberculosis

Pratibha Singh1, V M Katoch2, K K Mohanty3

  • 1Department of Microbiology & Molecular Biology, National JALMA Institute for Leprosy & Other Mycobacterial Diseases (ICMR), Agra, India.

The Indian Journal of Medical Research
|July 6, 2016
PubMed
Abstract

Insights

Mycobacterium tuberculosis mammalian cell entry (mce) operon genes show increased expression in the stationary growth phase, suggesting a role in pathogen survival and adaptation. This study analyzed mce gene trends across different M. tuberculosis isolates and growth stages.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Tuberculosis Research

Background:

  • Mycobacterium tuberculosis possesses four mammalian cell entry (mce) operons involved in virulence.
  • The complex expression patterns of mce operons are not fully understood.
  • Previous studies focused on in vitro growth phases, but not across different M. tuberculosis isolates.

Purpose of the Study:

  • To investigate the expression patterns of selected mce operon genes in different M. tuberculosis isolates.
  • To compare mce operon gene expression across early exponential and stationary growth phases.
  • To understand the role of mce operons in M. tuberculosis adaptation and survival.

Main Methods:

  • Real-time quantitative PCR was used to monitor transcriptional profiles.
  • Selected mce operon genes (mce1A, mce1D, mce2A, mce2D, mce3A, mce3C) were analyzed.
  • Expression was studied in MDR and sensitive M. tuberculosis isolates during early exponential and stationary phases.

Main Results:

  • All studied mce operon genes exhibited reduced expression in the initial growth phase.
  • A substantial increase in mce operon gene expression was observed in the later growth phase.
  • mce1 operon genes showed higher expression compared to mce2 and mce3 operons in the stationary phase.

Conclusions:

  • Mce operon gene expression is dependent on the growth phase.
  • Mce operon genes likely contribute to M. tuberculosis survival during adverse conditions, such as the stationary phase.
  • Understanding differential gene expression aids in comprehending M. tuberculosis adaptation strategies.

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