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The hydrolase LpqI primes mycobacterial peptidoglycan recycling.

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 ?-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.

SUBMITTER: Moynihan PJ

PROVIDER: S-EPMC6572805 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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The hydrolase LpqI primes mycobacterial peptidoglycan recycling.

Moynihan Patrick J PJ Cadby Ian T IT Veerapen Natacha N Jankute Monika M Crosatti Marialuisa M Mukamolova Galina V GV Lovering Andrew L AL Besra Gurdyal S GS

Nature communications 20190614 1

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 tuberculosi ...[more]

PMID: 31201321

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