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The mammalian cell entry operon 1 (mce1) of mycobacterium leprae and mycobacterium tuberculosis

H G Wiker1, E Spierings, M A Kolkman

  • 1Institute of Immunology, University of Oslo, The National Hospital, Oslo, N-0027, Norway.

Microbial Pathogenesis
|August 24, 1999
PubMed

Insights

Mycobacterium tuberculosis and Mycobacterium leprae share functional mammalian cell entry (mce1) operons. These operons are crucial for mycobacteria

Area of Science:

  • Microbiology
  • Genomics
  • Molecular Biology

Background:

  • The Mycobacterium tuberculosis H37Rv genome contains four mammalian cell entry (MTmce1-4) operons.
  • These operons are hypothesized to play a role in mycobacterial entry and survival within host cells.

Purpose of the Study:

  • To investigate the presence and functionality of a homologous operon in Mycobacterium leprae.
  • To correct sequencing errors in the identified Mycobacterium leprae mce1 operon.

Main Methods:

  • Comparative genomic analysis of Mycobacterium tuberculosis and Mycobacterium leprae.
  • Targeted sequencing to identify and correct sequence errors.

Main Results:

  • A homologous mce1 operon was identified in Mycobacterium leprae.
  • Sequence errors causing frame shifts in key genes were identified and corrected.
  • The corrected Mycobacterium leprae mce1 operon shows high homology to the Mycobacterium tuberculosis counterpart and encodes eight potential genes.

Conclusions:

  • Both Mycobacterium tuberculosis and Mycobacterium leprae mce1 operons are likely functional.
  • The mce1 operons in both species may be involved in host cell targeting by mycobacteria.

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