In:
Microbiology Spectrum, American Society for Microbiology, Vol. 7, No. 4 ( 2019-07-19)
Abstract:
Mycobacteria, including the infamous pathogen Mycobacterium tuberculosis , are high-GC Gram-positive bacteria with a distinctive cell envelope. Although there is a typical inner membrane, the mycobacterial cell envelope is unusual in having its peptidoglycan layer connected to a polymer of arabinogalactan, which in turn is covalently attached to long-chain mycolic acids that help form a highly impermeable mycobacterial outer membrane. This complex double-membrane, or diderm, cell envelope imparts mycobacteria with unique requirements for protein export into and across the cell envelope for secretion into the extracellular environment. In this article, we review the four protein export pathways known to exist in mycobacteria: two conserved systems that exist in all types of bacteria (the Sec and Tat pathways) and two specialized systems that exist in mycobacteria, corynebacteria, and a subset of low-GC Gram-positive bacteria (the SecA2 and type VII secretion pathways). We describe the progress made over the past 15 years in understanding each of these mycobacterial export pathways, and we highlight the need for research to understand the specific steps of protein export across the mycobacterial outer membrane.
Type of Medium:
Online Resource
ISSN:
2165-0497
DOI:
10.1128/microbiolspec.GPP3-0043-2018
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2019
detail.hit.zdb_id:
2807133-5
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