Peptide chemotaxis in E. coli involves the Tap signal transducer and the dipeptide permease
Abstract
Bacterial chemotaxis provides a simple model system for the more complex sensory responses of multicellular eukaryotic organisms1. In Escherichia coli, methylation and demethylation of four related membrane proteins, the methyl-accepting chemotaxis proteins (or MCPs), is central to chemotactic sensing and signal transduction2. Three of these proteins, Tar, Tsr and Trg, have been assigned specific roles in chemotaxis. However, the role of the fourth MCP, Tap, has remained obscure3. We demonstrate here that Tap functions as a conventional signal transducer, enabling the cell to respond chemotactically to dipeptides. This provides the first evidence of specific bacterial chemotaxis towards peptides. Peptide taxis requires the function of a periplasmic component of the dipeptide permease. This protein represents the first example of a periplasmic chemoreceptor that does not have a sugar substrate.
- Publication:
-
Nature
- Pub Date:
- May 1986
- DOI:
- 10.1038/321253a0
- Bibcode:
- 1986Natur.321..253M