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Electroporation of Mycobacteria
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Electroporation of Mycobacteria

Published on: May 23, 2008

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Protein Export into and across the Atypical Diderm Cell Envelope of Mycobacteria

Vincent J C van Winden1, Edith N G Houben2, Miriam Braunstein3

  • 1Department of Medical Microbiology and Infection Control, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands.

Microbiology Spectrum
|August 11, 2019
PubMed

Insights

Mycobacteria possess a unique double-membrane cell envelope requiring specialized protein export. This review covers conserved (Sec, Tat) and specialized (SecA2, type VII) secretion pathways, highlighting research needs for outer membrane transport.

Area of Science:

  • Microbiology
  • Cell Biology
  • Bacterial Pathogenesis

Background:

  • Mycobacteria feature a complex, high-GC Gram-positive cell envelope with an outer membrane.
  • This unique structure necessitates specialized protein export mechanisms for extracellular secretion.

Purpose of the Study:

  • To review the four known protein export pathways in mycobacteria.
  • To summarize recent advancements in understanding these pathways over the past 15 years.
  • To identify critical research gaps in mycobacterial protein export.

Main Methods:

  • Literature review of protein export pathways in mycobacteria.
  • Analysis of conserved (Sec, Tat) and specialized (SecA2, type VII) secretion systems.
  • Synthesis of research progress and future directions.

Main Results:

  • Four protein export pathways identified: Sec, Tat, SecA2, and type VII secretion.
  • Significant progress in understanding SecA2 and type VII pathways in mycobacteria.
  • Conserved Sec and Tat pathways also play roles in mycobacterial protein export.

Conclusions:

  • Mycobacterial protein export relies on both conserved and specialized pathways.
  • Further research is crucial to elucidate protein transport across the mycobacterial outer membrane.
  • Understanding these pathways is key to targeting mycobacterial infections.

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