Regulation of bacterial cell wall growth

• Published in: The FEBS journal 2017-03, Vol.284 (6), p.851-867
• Main Authors: Egan, Alexander J. F., Cleverley, Robert M., Peters, Katharina, Lewis, Richard J., Vollmer, Waldemar
• Format: Article
• Language: English
• Subjects: Antibiotics; Bacteria; Cell Membrane - genetics; Cell Membrane - metabolism; Cell membranes; Cell size; Cell Wall - genetics; Cell Wall - metabolism; Cell walls; Cellular biology; Cytoskeleton; Cytoskeleton - genetics; Cytoskeleton - metabolism; divisome; elongasome; Enzymes; Escherichia coli - genetics; Escherichia coli - growth & development; Growth conditions; Kinases; Mechanical properties; Metabolism; Multienzyme complexes; Multienzyme Complexes - genetics; penicillin‐binding protein; peptidoglycan; Peptidoglycan - biosynthesis; Peptidoglycan - metabolism; Peptidoglycans; Phosphorylation; Protein biosynthesis; Protein interaction; Protein Interaction Maps - genetics; protein phosphorylation; Proteins; Saccule; Scaffolding; Synthesis
• ISSN: 1742-464X; 1742-4658
• DOI: 10.1111/febs.13959

During growth and propagation, a bacterial cell enlarges and subsequently divides its peptidoglycan (PG) sacculus, a continuous mesh‐like layer that encases the cell membrane to confer mechanical strength and morphological robustness. The mechanism of sacculus growth, how it is regulated and how it is coordinated with other cellular processes is poorly understood. In this article, we will discuss briefly the current knowledge of how cell wall synthesis is regulated, on multiple levels, from both sides of the cytoplasmic membrane. According to the current knowledge, cytosolic scaffolding proteins connect PG synthases with cytoskeletal elements, and protein phosphorylation regulates cell wall growth in Gram‐positive species. PG‐active enzymes engage in multiple protein–protein interactions within PG synthesis multienzyme complexes, and some of the interactions modulate activities. PG synthesis is also regulated by central metabolism, and by PG maturation through the action of PG hydrolytic enzymes. Only now are we beginning to appreciate how these multiple levels of regulating PG synthesis enable the cell to propagate robustly with a defined cell shape under different and variable growth conditions. We review how bacterial cell wall growth is regulated on multiple levels. We outline the assembly of synthesis complexes through protein scaffolding and how dynamic protein–protein interactions control cell wall growth. We also discuss other regulatory inputs including phosphorylation of key regulatory proteins, cell wall maturation and coordination of cell wall growth with central metabolism through sensing nutrient availability.