Structural highlights
Function
[LUXS_BACSU] Involved in the synthesis of autoinducer 2 (AI-2) which is secreted by bacteria and is used to communicate both the cell density and the metabolic potential of the environment. The regulation of gene expression in response to changes in cell density is called quorum sensing. Catalyzes the transformation of S-ribosylhomocysteine (RHC) to homocysteine (HC) and 4,5-dihydroxy-2,3-pentadione (DPD).[HAMAP-Rule:MF_00091]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
In bacteria, the regulation of gene expression in response to changes in cell density is called quorum sensing. The autoinducer-2 production protein LuxS, is involved in a novel quorum-sensing system and is thought to catalyse the degradation of S-ribosylhomocysteine to homocysteine and the autoinducer molecule 4,5-dihydroxy-2,3-pentadione. The crystal structure of Bacillus subtilis LuxS has been determined at 1.2 A resolution, together with the binary complexes of LuxS with S-ribosylhomocysteine and homocysteine to 2.2 and 2.3 A resolution, respectively. These structures show that LuxS is a homodimer with an apparently novel fold based on an eight-stranded beta-barrel, flanked by six alpha-helices. Each active site contains a zinc ion coordinated by the conserved residues His54, His58 and Cys126, and includes residues from both subunits. S-ribosylhomocysteine binds in a deep pocket with the ribose moiety adjacent to the enzyme-bound zinc ion. Access to the active site appears to be restricted and possibly requires conformational changes in the protein involving the movement of residues 125-129 and those at the N terminus. The structure contains an oxidised cysteine residue in the active site whose role in the biological process of LuxS has not been determined. The autoinducer-2 signalling pathway has been linked to aspects of bacterial virulence and pathogenicity. The structural data on LuxS will provide opportunities for targeting this enzyme for the rational design of new antibiotics.
The 1.2 A structure of a novel quorum-sensing protein, Bacillus subtilis LuxS.,Ruzheinikov SN, Das SK, Sedelnikova SE, Hartley A, Foster SJ, Horsburgh MJ, Cox AG, McCleod CW, Mekhalfia A, Blackburn GM, Rice DW, Baker PJ J Mol Biol. 2001 Oct 12;313(1):111-22. PMID:11601850[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Ruzheinikov SN, Das SK, Sedelnikova SE, Hartley A, Foster SJ, Horsburgh MJ, Cox AG, McCleod CW, Mekhalfia A, Blackburn GM, Rice DW, Baker PJ. The 1.2 A structure of a novel quorum-sensing protein, Bacillus subtilis LuxS. J Mol Biol. 2001 Oct 12;313(1):111-22. PMID:11601850 doi:10.1006/jmbi.2001.5027
