Structure of a bacterial quorum-sensing transcription factor complexed with pheromone and DNA.

Journal Article · Thu Jun 27 04:00:00 EDT 2002 · Nature

DOI:https://doi.org/10.1038/nature00833· OSTI ID:949631

Zhang, R; Pappas, T; Brace, J; Miller, P; Oulmassov, T; Molyneaux, J; Anderson, J; Bashkin, J; Winans, S; Joachimiak, A; Monsanto, Co

Many proteobacteria are able to monitor their population densities through the release of pheromones known as N-acylhomoserine lactones. At high population densities, these pheromones elicit diverse responses that include bioluminescence, biofilm formation, production of antimicrobials, DNA exchange, pathogenesis and symbiosis1. Many of these regulatory systems require a pheromone-dependent transcription factor similar to the LuxR protein of Vibrio fischeri. Here we present the structure of a LuxR-type protein. TraR of Agrobacterium tumefaciens was solved at 1.66 A as a complex with the pheromone N-3-oxooctanoyl-l-homoserine lactone (OOHL) and its TraR DNA-binding site. The amino-terminal domain of TraR is an {alpha}/{beta}/{alpha} sandwich that binds OOHL, whereas the carboxy-terminal domain contains a helix-turn-helix DNA-binding motif. The TraR dimer displays a two-fold symmetry axis in each domain; however, these two axes of symmetry are at an approximately 90 degree angle, resulting in a pronounced overall asymmetry of the complex. The pheromone lies fully embedded within the protein with virtually no solvent contact, and makes numerous hydrophobic contacts with the protein as well as four hydrogen bonds: three direct and one water-mediated.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 949631
• Report Number(s): ANL/BIO/JA-42727
• Journal Information: Nature, Journal Name: Nature Journal Issue: 6892 ; Jun. 27, 2002 Vol. 417
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

08 HYDROGEN
ASYMMETRY
BIOLUMINESCENCE
DIMERS
DNA
HYDROGEN
LACTONES
MONITORS
PATHOGENESIS
PHEROMONE
PRODUCTION
PROTEINS
SOLVENTS
SYMMETRY
TRANSCRIPTION FACTORS