Coordination of peptidoglycan synthesis and outer membrane constriction during Escherichia coli cell division

Elife. 2015 May 7;4:e07118. doi: 10.7554/eLife.07118.

Abstract

To maintain cellular structure and integrity during division, Gram-negative bacteria must carefully coordinate constriction of a tripartite cell envelope of inner membrane, peptidoglycan (PG), and outer membrane (OM). It has remained enigmatic how this is accomplished. Here, we show that envelope machines facilitating septal PG synthesis (PBP1B-LpoB complex) and OM constriction (Tol system) are physically and functionally coordinated via YbgF, renamed CpoB (Coordinator of PG synthesis and OM constriction, associated with PBP1B). CpoB localizes to the septum concurrent with PBP1B-LpoB and Tol at the onset of constriction, interacts with both complexes, and regulates PBP1B activity in response to Tol energy state. This coordination links PG synthesis with OM invagination and imparts a unique mode of bifunctional PG synthase regulation by selectively modulating PBP1B cross-linking activity. Coordination of the PBP1B and Tol machines by CpoB contributes to effective PBP1B function in vivo and maintenance of cell envelope integrity during division.

Keywords: E. coli; cell division; cell envelope; infectious disease; microbiology; outer membrane; peptidoglycan.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Division / physiology*
  • Cell Membrane / metabolism
  • Cell Membrane / physiology*
  • Chlorophenols
  • DNA Primers / genetics
  • Escherichia coli / physiology*
  • Escherichia coli Proteins / metabolism*
  • Galactosides
  • Gene Knockout Techniques
  • Image Processing, Computer-Assisted
  • Membrane Proteins / metabolism*
  • Microscopy, Fluorescence
  • Penicillin-Binding Proteins / metabolism
  • Peptidoglycan / biosynthesis*
  • Peptidoglycan Glycosyltransferase / metabolism
  • Plasmids / genetics
  • Serine-Type D-Ala-D-Ala Carboxypeptidase / metabolism

Substances

  • Chlorophenols
  • DNA Primers
  • Escherichia coli Proteins
  • Galactosides
  • Membrane Proteins
  • Penicillin-Binding Proteins
  • Peptidoglycan
  • YbgF protein, E coli
  • chlorophenol red galactopyranoside
  • Peptidoglycan Glycosyltransferase
  • penicillin-binding protein 1B, E coli
  • Serine-Type D-Ala-D-Ala Carboxypeptidase