IUBMB Enzyme Nomenclature


Accepted name: S-ribosylhomocysteine lyase

Reaction: S-(5-deoxy-D-ribos-5-yl)-L-homocysteine = L-homocysteine + (4S)-4,5-dihydroxypentan-2,3-dione

For diagram click here.

Other name(s): S-ribosylhomocysteinase; LuxS

Systematic name: S-(5-deoxy-D-ribos-5-yl)-L-homocysteine homocysteine-lyase [(4S)-4,5-dihydroxypentan-2,3-dione-forming]

Comments: Contains Fe2+. The 4,5-dihydroxypentan-2,3-dione formed spontaneously cyclizes and combines with borate to form an autoinducer (AI-2) in the bacterial quorum-sensing mechanism, which is used by many bacteria to control gene expression in response to cell density [2].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37288-63-4


1. Zhu, J., Dizin, E., Hu, X., Wavbreille, A.S., Park, J. and Pei, D. S-Ribosylhomocysteinase (LuxS) is a mononuclear iron protein. Biochemistry 42 (2003) 4717-4726. [PMID: 12705835]

2. Miller, M.B. and Bassler, B.L. Quorum sensing in bacteria. Annu. Rev. Microbiol. 55 (2001) 165-199. [PMID: 11544353]

[EC created 2004]

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