Peptidoglycan precursor synthesis along the sidewall of pole-growing mycobacteria

eLife

Benjamin M Swarts¹  Sarah R Rundell²  Taylor J Fiolek²  M Sloan Siegrist²  Jeffrey C Wagner³  Hoong Chuin Lim⁴  Amol Arunrao Pohane⁵  Caleb R Carr⁵  Emily S Melzer⁵  Alam García-Heredia⁶  Yasu S Morita⁶ 

[1] Department of Microbiology, University of Massachusetts, Amherst, United States;Department of Chemistry and Biochemistry, Central Michigan University, Mount Pleasant, United States;Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, United States;Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States;Department of Microbiology, University of Massachusetts, Amherst, United States;Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, United States;

关键词: mycobacterium tuberculosis;    peptidoglycan;    cell wall;    metabolic labeling;    d-amino acid;    mycomembrane;   

DOI  :  10.7554/eLife.37243

来源: DOAJ

【 摘 要 】

Rod-shaped mycobacteria expand from their poles, yet d-amino acid probes label cell wall peptidoglycan in this genus at both the poles and sidewall. We sought to clarify the metabolic fates of these probes. Monopeptide incorporation was decreased by antibiotics that block peptidoglycan synthesis or l,d-transpeptidation and in an l,d-transpeptidase mutant. Dipeptides complemented defects in d-alanine synthesis or ligation and were present in lipid-linked peptidoglycan precursors. Characterizing probe uptake pathways allowed us to localize peptidoglycan metabolism with precision: monopeptide-marked l,d-transpeptidase remodeling and dipeptide-marked synthesis were coincident with mycomembrane metabolism at the poles, septum and sidewall. Fluorescent pencillin-marked d,d-transpeptidation around the cell perimeter further suggested that the mycobacterial sidewall is a site of cell wall assembly. While polar peptidoglycan synthesis was associated with cell elongation, sidewall synthesis responded to cell wall damage. Peptidoglycan editing along the sidewall may support cell wall robustness in pole-growing mycobacteria.

【 授权许可】

Unknown