1INN: Crystal Structure Of D. Radiodurans Luxs, P21

BACKGROUND: Quorum sensing is the mechanism by which bacteria control gene expression in response to cell density. Two major quorum-sensing systems have been identified, system 1 and system 2, each with a characteristic signaling molecule (autoinducer-1, or AI-1, in the case of system 1, and AI-2 in system 2). The luxS gene is required for the AI-2 system of quorum sensing. LuxS and AI-2 have been described in both Gram-negative and Gram-positive bacterial species and have been shown to be involved in the expression of virulence genes in several pathogens. RESULTS: The structure of the LuxS protein from three different bacterial species with resolutions ranging from 1.8 A to 2.4 A has been solved using an X-ray crystallographic structural genomics approach. The structure of LuxS reported here is seen to have a new alpha-beta fold. In all structures, an equivalent homodimer is observed. A metal ion identified as zinc was seen bound to a Cys-His-His triad. Methionine was found bound to the protein near the metal and at the dimer interface. CONCLUSIONS: These structures provide support for a hypothesis that explains the in vivo action of LuxS. Specifically, acting as a homodimer, the protein binds a methionine analog, S-ribosylhomocysteine (SRH). The zinc atom is in position to cleave the ribose ring in a step along the synthesis pathway of AI-2.
PDB ID: 1INNDownload
MMDB ID: 16734
PDB Deposition Date: 2001/5/14
Updated in MMDB: 2017/10
Experimental Method:
x-ray diffraction
Resolution: 1.8  Å
Source Organism:
Similar Structures:
Biological Unit for 1INN: dimeric; determined by author and by software (PISA)
Molecular Components in 1INN
Label Count Molecule
Proteins (2 molecules)
Autoinducer-2 Production Protein Luxs(Gene symbol: DR_2387)
Molecule annotation
Chemicals (3 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB