Targeting and translocation of two lipoproteins in Escherichia coli via the SRP/Sec/YidC pathway

J Biol Chem. 2004 Jul 23;279(30):31026-32. doi: 10.1074/jbc.M403229200. Epub 2004 May 12.

Abstract

In Escherichia coli, two main protein targeting pathways to the inner membrane exist: the SecB pathway for the essentially posttranslational targeting of secretory proteins and the SRP pathway for cotranslational targeting of inner membrane proteins (IMPs). At the inner membrane both pathways converge at the Sec translocase, which is capable of both linear transport into the periplasm and lateral transport into the lipid bilayer. The Sec-associated YidC appears to assist the lateral transport of IMPs from the Sec translocase into the lipid bilayer. It should be noted that targeting and translocation of only a handful of secretory proteins and IMPs have been studied. These model proteins do not include lipoproteins. Here, we have studied the targeting and translocation of two secretory lipoproteins, the murein lipoprotein and the bacteriocin release protein, using a combined in vivo and in vitro approach. The data indicate that both murein lipoprotein and bacteriocin release protein require the SRP pathway for efficient targeting to the Sec translocase. Furthermore, we show that YidC plays an important role in the targeting/translocation of both lipoproteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism
  • Amino Acid Sequence
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Bacteriocins / metabolism
  • Cross-Linking Reagents
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Lipoproteins / genetics
  • Lipoproteins / metabolism*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Molecular Sequence Data
  • SEC Translocation Channels
  • SecA Proteins
  • Sequence Homology, Amino Acid
  • Signal Recognition Particle / genetics
  • Signal Recognition Particle / metabolism

Substances

  • Bacterial Proteins
  • Bacteriocins
  • Cross-Linking Reagents
  • Escherichia coli Proteins
  • Lipoproteins
  • Membrane Transport Proteins
  • SEC Translocation Channels
  • Signal Recognition Particle
  • YIDC protein, E coli
  • cloacin DF13-encoded bacteriocin release protein, E coli
  • Adenosine Triphosphatases
  • SecA Proteins