The hydrolase LpqI primes mycobacterial peptidoglycan recycling

Nat Commun. 2019 Jun 14;10(1):2647. doi: 10.1038/s41467-019-10586-2.

Abstract

Growth and division by most bacteria requires remodelling and cleavage of their cell wall. A byproduct of this process is the generation of free peptidoglycan (PG) fragments known as muropeptides, which are recycled in many model organisms. Bacteria and hosts can harness the unique nature of muropeptides as a signal for cell wall damage and infection, respectively. Despite this critical role for muropeptides, it has long been thought that pathogenic mycobacteria such as Mycobacterium tuberculosis do not recycle their PG. Herein we show that M. tuberculosis and Mycobacterium bovis BCG are able to recycle components of their PG. We demonstrate that the core mycobacterial gene lpqI, encodes an authentic NagZ β-N-acetylglucosaminidase and that it is essential for PG-derived amino sugar recycling via an unusual pathway. Together these data provide a critical first step in understanding how mycobacteria recycle their peptidoglycan.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylglucosaminidase / metabolism*
  • Antibiotics, Antitubercular / pharmacology
  • Bacterial Proteins / metabolism*
  • Cell Wall / chemistry
  • Cell Wall / metabolism
  • Drug Resistance, Bacterial
  • Microbial Sensitivity Tests
  • Muramic Acids / metabolism
  • Muramidase / pharmacology
  • Mycobacterium bovis / chemistry
  • Mycobacterium bovis / metabolism*
  • Mycobacterium tuberculosis / chemistry
  • Mycobacterium tuberculosis / metabolism*
  • Peptidoglycan / chemistry
  • Peptidoglycan / metabolism*

Substances

  • Antibiotics, Antitubercular
  • Bacterial Proteins
  • Muramic Acids
  • Peptidoglycan
  • N-acetylmuramic acid
  • Muramidase
  • Acetylglucosaminidase