Work

Secondary extended mannan side chains and attachment of the arabinan in mycobacterial lipoarabinomannan

Year: 2020

Type: article

Abstract: Mycobacterial lipoarabinomannan (LAM) in an essential cell envelope lipopolysaccharide anchored both to the plasma and outer membranes. To understand critical biological questions such as the biosynthesis, spatial organization of LAM within the cell envelope, structural remodeling during growth, and display or lack of display of LAM-based antigenicity all requires a basic understanding of the primary structure of the mannan, arabinan and how they are attached to each other. Herein, using enzymatic digestions and high-resolution mass spectrometry, we show that the arabinan component of LAM is attached at the non-reducing end of the mannan rather than to internal regions. Further, we show the presence of secondary extended mannan side chains attached to the internal mannan region. Such findings lead to a significant revision of the structure of LAM and lead to guidance of biosynthetic studies and to hypotheses of the role of LAM both in the periplasm and outside the cell as a fundamental part of the dynamic mycobacterial cell envelope.

Source: Communications Chemistry

DOI: 10.1038/s42004-020-00356-3

Authors: Shiva K. Angala, Wei Li, Claudia M. Boot, Mary Jackson, Michael R. McNeil

Institution: Colorado State University

Language: English

Topic: Tuberculosis Research and Epidemiology

Subfield: Infectious Diseases

Field: Medicine

Domain: Health Sciences

Open Access status: gold

Estimated APC paid: $3,290

Funders: National Institutes of Health, National Institute of Allergy and Infectious Diseases