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From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
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Transporters Involved in the Biogenesis and Functionalization of the Mycobacterial Cell Envelope

Mary Jackson1, Casey M Stevens2, Lei Zhang3

  • 1Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523-1682, United States.

Chemical Reviews
|November 10, 2020
PubMed

Insights

Mycobacteria

Area of Science:

  • Microbiology
  • Cell Biology
  • Biochemistry

Background:

  • Mycobacteria possess a complex, low-permeability cell envelope crucial for pathogenicity and antibiotic resistance.
  • This unique cell envelope structure presents challenges for nutrient uptake and the translocation of essential molecules.
  • Understanding mycobacterial cell envelope biogenesis is vital for developing new therapeutic strategies.

Purpose of the Study:

  • To review the transporters involved in assembling and functionalizing the mycobacterial cell envelope.
  • To highlight current knowledge and limitations in understanding the translocation of cell envelope components.
  • To describe mycobacterial strategies for nutrient import across their impermeable barrier.

Main Methods:

  • Literature review of studies on mycobacterial cell envelope transport systems.
  • Analysis of research on the translocation of (lipo)polysaccharides, (glyco)lipids, and secreted products.
  • Examination of mechanisms for nutrient import in mycobacteria.

Main Results:

  • Significant progress has been made in identifying transporters for cell envelope components.
  • Gaps remain in understanding the precise mechanisms of translocation across all cell envelope layers.
  • Mycobacteria employ specialized strategies to acquire nutrients through their impermeable outer layers.

Conclusions:

  • Transporter systems are key to the assembly and function of the mycobacterial cell envelope.
  • Further research is needed to fully elucidate these transport mechanisms and their therapeutic implications.
  • Understanding these processes can reveal novel targets for combating mycobacterial infections.

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