HMM Summary Page: TIGR03462

Functionlycopene cyclase domain
Trusted Cutoff39.40
Domain Trusted Cutoff39.40
Noise Cutoff29.50
Domain Noise Cutoff29.50
Isology Typesubfamily_domain
HMM Length89
AuthorSelengut J
Entry DateJul 30 2007 2:02PM
Last ModifiedDec 21 2011 12:25PM
CommentThis domain is often repeated twice within the same polypeptide, as is observed in Archaea, Thermus, Sphingobacteria [1] and Fungi. In the fungal sequences, this tandem domain pair is observed as the N-terminal half of a bifunctional protein [2], where it has been characterized as a lycopene beta-cyclase and the C-terminal half is a phytoene synthetase. In Myxococcus and Actinobacterial genomes this domain appears as a single polypeptide, tandemly repeated and usually in a genomic context consistent with a role in carotenoid biosynthesis. It is unclear whether any of the sequences in this family truly encode lycopene epsilon cyclases. However a number are annotated as such. The domain is generally hydrophobic with a number of predicted membrane spanning segments and contains a distinctive motif (hPhEEhhhhhh). In certain sequences one of either the proline or glutamates may vary, but always one of the tandem pair appear to match this canonical sequence exactly.
ReferencesRN [1] RM PMID:16625353 RT A carotenoid synthesis gene cluster from Algoriphagus sp. KK10202C with a novel fusion-type lycopene beta-cyclase gene. RA Tao L, Yao H, Kasai H, Misawa N, Cheng Q RL Mol Genet Genomics. 2006 Jul;276(1):79-86. Epub 2006 Apr 20. RN [2] RM PMID:10951210 RT A bifunctional enzyme with lycopene cyclase and phytoene synthase activities is encoded by the carRP gene of Mucor circinelloides. RA Velayos A, Eslava AP, Iturriaga EA RL Eur J Biochem. 2000 Sep;267(17):5509-19.
Genome PropertyGenProp0758: lycopene biosynthesis from IPP (HMM)