The gene encoding P27 lipoprotein and a putative antibiotic-resistance gene form an operon in Mycobacterium

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Analysis of the Lipid Composition of Mycobacteria by Thin Layer Chromatography
07:42

Analysis of the Lipid Composition of Mycobacteria by Thin Layer Chromatography

Published on: April 16, 2021

F Bigi1, A Alito1, M I Romano1

  • 1Instituto de Biotecnologı́a1 and Instituto de Patobiologı́a2, CICV-INTA, PO Box 77, Castelar, Argentina.

Microbiology (Reading, England)
|April 28, 2000
PubMed

Insights

The P27/P55 operon in Mycobacterium tuberculosis complex members is transcribed from two distinct promoters in Mycobacterium bovis BCG. This finding advances our understanding of gene regulation in pathogenic mycobacteria.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • P27 is an antigenic membrane lipoprotein found in the Mycobacterium tuberculosis complex.
  • P27 and a putative antibiotic transporter (P55) are encoded by genes that form an operon.

Purpose of the Study:

  • To identify and characterize the promoter region of the P27/P55 operon.
  • To determine the transcription initiation points and promoter sequences in Mycobacterium bovis BCG.

Main Methods:

  • Northern blotting and RT-PCR were used to confirm the operon structure.
  • Deletion analysis in Mycobacterium smegmatis identified the promoter region.
  • Primer extension analysis in Mycobacterium bovis BCG mapped transcription initiation sites.

Main Results:

  • The P27 and P55 genes form an operon.
  • Two transcription initiation points were identified 76 bp and 87 bp upstream of the ATG codon in M. bovis BCG.
  • The identified promoter sequences exhibited 66% similarity to known mycobacterial promoters.

Conclusions:

  • The P27/P55 operon in M. bovis BCG is transcribed from at least two promoters.
  • This study characterizes the transcriptional regulation of a key operon in pathogenic mycobacteria.

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