Skip to main content
padlock icon - secure page this page is secure

Free Content Interaction between two murein (peptidoglycan) synthases, PBP3 and PBP1B, in Escherichia coli

Download Article:
 Download
(PDF 597.4 kb)
 
Summary

The murein (peptidoglycan) sacculus is an essential polymer embedded in the bacterial envelope. The Escherichia coli class B penicillin-binding protein (PBP) 3 is a murein transpeptidase and essential for cell division. In an affinity chromatography experiment, the bifunctional transglycosylase-transpeptidase murein synthase PBP1B was retained by PBP3-sepharose when a membrane fraction of E. coli was applied. The direct protein–protein interaction between purified PBP3 and PBP1B was characterized in vitro by surface plasmon resonance. The interaction was confirmed in vivo employing two different methods: by a bacterial two-hybrid system, and by cross-linking/co-immunoprecipitation. In the bacterial two-hybrid system, a truncated PBP3 comprising the N-terminal 56 amino acids interacted with PBP1B. Both synthases could be cross-linked in vivo in wild-type cells and in cells lacking FtsW or FtsN. PBP1B localized diffusely and in foci at the septation site and also at the side wall. Statistical analysis of the immunofluorescence signals revealed that the localization of PBP1B at the septation site depended on the physical presence of PBP3, but not on the activity of PBP3. These studies have demonstrated, for the first time, a direct interaction between a class B PBP (PBP3) and a class A PBP (PBP1B) in vitro and in vivo, indicating that different murein synthases might act in concert to enlarge the murein sacculus during cell division.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Document Type: Research Article

Affiliations: 1: Mikrobielle Genetik, Universität Tübingen, D-72076 Tübingen, Auf der Morgenstelle 28, Germany. 2: Centre d'Ingénierie des Protéines, Institut de Chimie B6a, Université de Liège, B-4000 Sart Tilman, Belgium. 3: Swammerdam Institute for Life Sciences, Molecular Cytology, Kruislaan 316, 1098 SM Amsterdam, the Netherlands.

Publication date: August 1, 2006

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more