Quorum-sensing signal binding results in dimerization of TraR and its release from membranes into the cytoplasm
- 2 October 2000
- journal article
- Published by Springer Nature in The EMBO Journal
- Vol. 19 (19) , 5212-5221
- https://doi.org/10.1093/emboj/19.19.5212
Abstract
Promoter binding by TraR and LuxR, the activators of two bacterial quorum‐sensing systems, requires their cognate acyl‐homoserine lactone (acyl‐HSL) signals, but the role the signal plays in activating these transcription factors is not known. Soluble active TraR, when purified from cells grown with the acyl‐HSL, contained bound signal and was solely in dimer form. However, genetic and cross‐linking studies showed that TraR is almost exclusively in monomer form in cells grown without signal. Adding signal resulted in dimerization of the protein in a concentration‐dependent manner. In the absence of signal, monomer TraR localized to the inner membrane while growth with the acyl‐HSL resulted in the appearance of dimer TraR in the cytoplasmic compartment. Affinity chromatography indicated that the N‐terminus of TraR from cells grown without signal is hidden. Analysis of heterodimers formed between TraR and its deletion mutants localized the dimerization domain to a region between residues 49 and 156. We conclude that binding signal drives dimerization of TraR and its release from membranes into the cytoplasm.Keywords
This publication has 47 references indexed in Scilit:
- Modulating quorum sensing by antiactivation: TraM interacts with TraR to inhibit activation of Ti plasmid conjugal transfer genesMolecular Microbiology, 1999
- Dimerization of the Agrobacterium tumefaciens VirB4 ATPase and the effect of ATP‐binding cassette mutations on the assembly and function of the T‐DNA transporterMolecular Microbiology, 1999
- Octopine-type Ti plasmids code for a mannopine-inducible dominant-negative allele of traR, the quorum-sensing activator that regulates Ti plasmid conjugal transferMolecular Microbiology, 1998
- Repressor fusions as a tool to study protein–protein interactionsStructure, 1995
- TraI, a LuxI homologue, is responsible for production of conjugation factor, the Ti plasmid N-acylhomoserine lactone autoinducer.Proceedings of the National Academy of Sciences, 1994
- GroESL proteins facilitate binding of externally added inducer by luxR protein‐containing E. coli cellsJournal of Bioluminescence and Chemiluminescence, 1993
- Conjugation factor of Agrobacterium tumefaciens regulates Ti plasmid transfer by autoinductionNature, 1993
- Agrobacterium conjugation and gene regulation by N-acyl-L-homoserine lactonesNature, 1993
- Two types of abnormal genes for plasminogen in families with a predisposition for thrombosis.Proceedings of the National Academy of Sciences, 1991
- Agrobacterium tumefaciens DNA and PS8 Bacteriophage DNA Not Detected in Crown Gall TumorsProceedings of the National Academy of Sciences, 1974