scholarly journals A cytoplasmic peptidoglycan amidase homologue controls mycobacterial cell wall synthesis

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Cara C Boutte ◽  
Christina E Baer ◽  
Kadamba Papavinasasundaram ◽  
Weiru Liu ◽  
Michael R Chase ◽  
...  
Keyword(s):  
Cell Wall ◽  
Antibiotic Tolerance ◽  
Bacterial Survival ◽  
Cell Wall Metabolism ◽  
Cell Wall Assembly ◽  
Enzymatic Function ◽  
Precursor Synthesis ◽  
Mycobacterial Cell Wall ◽  
Wall Assembly ◽  
Multiple Antibiotics

Regulation of cell wall assembly is essential for bacterial survival and contributes to pathogenesis and antibiotic tolerance in Mycobacterium tuberculosis (Mtb). However, little is known about how the cell wall is regulated in stress. We found that CwlM, a protein homologous to peptidoglycan amidases, coordinates peptidoglycan synthesis with nutrient availability. Surprisingly, CwlM is sequestered from peptidoglycan (PG) by localization in the cytoplasm, and its enzymatic function is not essential. Rather, CwlM is phosphorylated and associates with MurA, the first enzyme in PG precursor synthesis. Phosphorylated CwlM activates MurA ~30 fold. CwlM is dephosphorylated in starvation, resulting in lower MurA activity, decreased cell wall metabolism, and increased tolerance to multiple antibiotics. A phylogenetic analysis of cwlM implies that localization in the cytoplasm drove the evolution of this factor. We describe a system that controls cell wall metabolism in response to starvation, and show that this regulation contributes to antibiotic tolerance.

scholarly journals The mycobacterial cell wall partitions the plasma membrane to organize its own synthesis

2019 ◽  
Author(s):  
Alam García-Heredia ◽  
Takehiro Kado ◽  
Caralyn E. Sein ◽  
Julia Puffal ◽  
Sarah H. Osman ◽  
...  
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Membrane Domains ◽  
Peptidoglycan Biosynthesis ◽  
Cell Wall Assembly ◽  
Peptidoglycan Synthesis ◽  
Cell Wall Biogenesis ◽  
Mycobacterial Cell Wall ◽  
Wall Assembly ◽  
Made In

AbstractMany antibiotics target the assembly of cell wall peptidoglycan, an essential, heteropolymeric mesh that encases most bacteria. Different species have characteristic subcellular sites of peptidoglycan synthesis that they must carefully maintain for surface integrity and, ultimately, viability. In rod-shaped bacteria, cell wall elongation is spatially precise yet relies on a limited pool of lipid-linked precursors that generate and are attracted to membrane disorder. By tracking enzymes, substrates and products of peptidoglycan biosynthesis in Mycobacterium smegmatis, we show that precursors are made in plasma membrane domains that are laterally and biochemically distinct from sites of cell wall assembly. Membrane partitioning is required for robust, orderly peptidoglycan synthesis, indicating that these domains help template peptidoglycan synthesis. The cell wall-organizing protein DivIVA and the cell wall itself are essential for domain homeostasis. Thus, the peptidoglycan polymer feeds back on its membrane template to maintain an environment conducive to directional synthesis. We further show that our findings are applicable to rod-shaped bacteria that are phylogenetically distant from M. smegmatis, demonstrating that horizontal compartmentalization of precursors is a general feature of bacillary cell wall biogenesis.

scholarly journals Peptidoglycan precursor synthesis along the sidewall of pole-growing mycobacteria

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Alam García-Heredia ◽  
Amol Arunrao Pohane ◽  
Emily S Melzer ◽  
Caleb R Carr ◽  
Taylor J Fiolek ◽  
...  
Keyword(s):  
Cell Wall ◽  
Amino Acid ◽  
Label Cell ◽  
Cell Wall Assembly ◽  
Support Cell ◽  
Peptidoglycan Synthesis ◽  
Precursor Synthesis ◽  
Alanine Synthesis ◽  
A Site ◽  
Wall Assembly

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.

scholarly journals Lcp1 Is a Phosphotransferase Responsible for Ligating Arabinogalactan to Peptidoglycan in Mycobacterium tuberculosis

mBio ◽  
2016 ◽  
Vol 7 (4) ◽  
Author(s):  
James Harrison ◽  
Georgina Lloyd ◽  
Maju Joe ◽  
Todd L. Lowary ◽  
Edward Reynolds ◽  
...  
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Essential Gene ◽  
Cell Envelope ◽  
New Drugs ◽  
Cell Wall Assembly ◽  
Mycobacterial Cell ◽  
Unique Cell ◽  
Mycobacterial Cell Wall ◽  
Wall Assembly

ABSTRACT Mycobacterium tuberculosis , the etiological agent of tuberculosis (TB), has a unique cell envelope which accounts for its unusual low permeability and contributes to resistance against common antibiotics. The main structural elements of the cell wall consist of a cross-linked network of peptidoglycan (PG) in which some of the muramic acid residues are covalently attached to a complex polysaccharide, arabinogalactan (AG), via a unique α- l -rhamnopyranose–(1→3)-α- d -GlcNAc-(1→P) linker unit. While the molecular genetics associated with PG and AG biosynthetic pathways have been largely delineated, the mechanism by which these two major pathways converge has remained elusive. In Gram-positive organisms, the LytR-CpsA-Psr (LCP) family of proteins are responsible for ligating cell wall teichoic acids to peptidoglycan, through a linker unit that bears a striking resemblance to that found in mycobacterial arabinogalactan. In this study, we have identified Rv3267 as a mycobacterial LCP homolog gene that encodes a phosphotransferase which we have named Lcp1. We demonstrate that lcp1 is an essential gene required for cell viability and show that recombinant Lcp1 is capable of ligating AG to PG in a cell-free radiolabeling assay. IMPORTANCE Tuberculosis is an infectious disease caused by the bacterial organism Mycobacterium tuberculosis . Survival of M. tuberculosis rests critically on the integrity of its unique cell wall; therefore, a better understanding of how the genes and enzymes involved in cell wall assembly work is fundamental for us to develop new drugs to treat this disease. In this study, we have identified Lcp1 as an essential phosphotransferase that ligates together arabinogalactan and peptidoglycan, two crucial cell wall macromolecules found within the mycobacterial cell wall. The discovery of Lcp1 sheds new light on the final stages of mycobacterial cell wall assembly and represents a key biosynthetic step that could be exploited for new anti-TB drug discovery.

scholarly journals Phosphorylation on PstP regulates cell wall metabolism and antibiotic tolerance in Mycobacterium smegmatis

2019 ◽  
Author(s):  
Farah Shamma ◽  
Kadamba Papavinasasundaram ◽  
Samantha Y. Quintanilla ◽  
Aditya Bandekar ◽  
Christopher Sassetti ◽  
...  
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Mycobacterium Smegmatis ◽  
Control Cell ◽  
Model Organism ◽  
Mycolic Acid ◽  
Regulatory Function ◽  
Antibiotic Tolerance ◽  
Bacterial Survival ◽  
Cell Wall Metabolism

AbstractMycobacterium tuberculosis and its relatives, like many bacteria, have dynamic cell walls that respond to environmental stresses. Modulation of cell wall metabolism in stress is thought to be responsible for decreased permeability and increased tolerance to antibiotics. The signaling systems that control cell wall metabolism under stress, however, are poorly understood. Here, we examine the cell wall regulatory function of a key cell wall regulator, the Serine Threonine Phosphatase PstP, in the model organism Mycobacterium smegmatis. We show that the peptidoglycan regulator CwlM is a substrate of PstP. We find that a phospho-mimetic mutation, pstP T171E, slows growth, mis-regulates both mycolic acid and peptidoglycan metabolism in different conditions, and interferes with antibiotic tolerance. These data suggest that phosphorylation on PstP affects its activity against various substrates and is important in the transition between growth and stasis.ImportanceRegulation of cell wall assembly is essential for bacterial survival and contributes to pathogenesis and antibiotic tolerance in mycobacteria, including pathogens such as Mycobacterium tuberculosis. However, little is known about how the cell wall is regulated in stress. We describe a pathway of cell wall modulation in Mycobacterium smegmatis through the only essential Ser/Thr phosphatase, PstP. We showed that phosphorylation on PstP is important in regulating peptidoglycan metabolism in the transition to stasis and mycolic acid metabolism in growth. This regulation also affects antibiotic tolerance in growth and stasis. This work helps us to better understand the phosphorylation-mediated cell wall regulation circuitry in Mycobacteria.

Synthesis and anti-mycobacterial activity of glycosyl sulfamides of arabinofuranose

2016 ◽  
Vol 14 (5) ◽  
pp. 1748-1754 ◽  
Author(s):  
Kajitha Suthagar ◽  
Antony J. Fairbanks
Keyword(s):  
Cell Wall ◽  
Hydroxyl Group ◽  
Cell Wall Assembly ◽  
Mycobacterial Cell ◽  
Furanose Form ◽  
Mycobacterial Cell Wall ◽  
Wall Assembly

A series ofarabino N-glycosyl sulfamides, forced to adopt the furanose form by removal of the 5-hydroxyl group, were synthesised as putative isosteric mimics of decaprenolphosphoarabinose, the donor processed by arabinosyltransferases during mycobacterial cell wall assembly.

scholarly journals Control of Cell Wall Assembly by a Histone-Like Protein in Mycobacteria

2007 ◽  
Vol 189 (22) ◽  
pp. 8241-8249 ◽  
Author(s):  
Tomoya Katsube ◽  
Sohkichi Matsumoto ◽  
Masaki Takatsuka ◽  
Megumi Okuyama ◽  
Yuriko Ozeki ◽  
...  
Keyword(s):  
Cell Wall ◽  
Wall Structure ◽  
Regulation Mechanism ◽  
Mycolic Acids ◽  
Growth State ◽  
Cell Wall Assembly ◽  
Cell Wall Biogenesis ◽  
Covalently Linked ◽  
Mycobacterial Cell Wall ◽  
Wall Assembly

ABSTRACT Bacteria coordinate assembly of the cell wall as well as synthesis of cellular components depending on the growth state. The mycobacterial cell wall is dominated by mycolic acids covalently linked to sugars, such as trehalose and arabinose, and is critical for pathogenesis of mycobacteria. Transfer of mycolic acids to sugars is necessary for cell wall biogenesis and is mediated by mycolyltransferases, which have been previously identified as three antigen 85 (Ag85) complex proteins. However, the regulation mechanism which links cell wall biogenesis and the growth state has not been elucidated. Here we found that a histone-like protein has a dual concentration-dependent regulatory effect on mycolyltransferase functions of the Ag85 complex through direct binding to both the Ag85 complex and the substrate, trehalose-6-monomycolate, in the cell wall. A histone-like protein-deficient Mycobacterium smegmatis strain has an unusual crenellated cell wall structure and exhibits impaired cessation of glycolipid biosynthesis in the growth-retarded phase. Furthermore, we found that artificial alteration of the amount of the extracellular histone-like protein and the Ag85 complex changes the growth rate of mycobacteria, perhaps due to impaired down-regulation of glycolipid biosynthesis. Our results demonstrate novel regulation of cell wall assembly which has an impact on bacterial growth.

scholarly journals Phosphorylation on PstP regulates cell wall metabolism and antibiotic tolerance in Mycobacterium smegmatis

2020 ◽  
Author(s):  
Farah Shamma ◽  
Kadamba Papavinasasundaram ◽  
Samantha Y. Quintanilla ◽  
Aditya Bandekar ◽  
Christopher Sassetti ◽  
...  
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Mycobacterium Smegmatis ◽  
Control Cell ◽  
Model Organism ◽  
Mycolic Acid ◽  
Regulatory Function ◽  
Antibiotic Tolerance ◽  
Bacterial Survival ◽  
Cell Wall Metabolism

Mycobacterium tuberculosis and its relatives, like many bacteria, have dynamic cell walls that respond to environmental stresses. Modulation of cell wall metabolism in stress is thought to be responsible for decreased permeability and increased tolerance to antibiotics. The signaling systems that control cell wall metabolism under stress, however, are poorly understood. Here, we examine the cell wall regulatory function of a key cell wall regulator, the Serine Threonine Phosphatase PstP, in the model organism Mycobacterium smegmatis. We show that the peptidoglycan regulator CwlM is a substrate of PstP. We find that a phospho-mimetic mutation, pstP T171E, slows growth, mis-regulates both mycolic acid and peptidoglycan metabolism in different conditions, and interferes with antibiotic tolerance. These data suggest that phosphorylation on PstP affects its activity against various substrates and is important in the transition between growth and stasis. Importance Regulation of cell wall assembly is essential for bacterial survival and contributes to pathogenesis and antibiotic tolerance in mycobacteria, including pathogens such as Mycobacterium tuberculosis. However, little is known about how the cell wall is regulated in stress. We describe a pathway of cell wall modulation in Mycobacterium smegmatis through the only essential Ser/Thr phosphatase, PstP. We showed that phosphorylation on PstP is important in regulating peptidoglycan metabolism in the transition to stasis and mycolic acid metabolism in growth. This regulation also affects antibiotic tolerance in growth and stasis. This work helps us to better understand the phosphorylation-mediated cell wall regulation circuitry in Mycobacteria.

Sign in / Sign up

Export Citation Format

Share Document