2uuu
From Proteopedia
alkyldihydroxyacetonephosphate synthase in P212121
Structural highlights
FunctionADAS_DICDI Catalyzes the exchange of an acyl for a long-chain alkyl group and the formation of the ether bond in the biosynthesis of ether phospholipids. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedEther phospholipids are essential constituents of eukaryotic cell membranes. Rhizomelic chondrodysplasia punctata type 3 is a severe peroxisomal disorder caused by inborn deficiency of alkyldihydroxyacetonephosphate synthase (ADPS). The enzyme carries out the most characteristic step in ether phospholipid biosynthesis: formation of the ether bond. The crystal structure of ADPS from Dictyostelium discoideum shows a fatty-alcohol molecule bound in a narrow hydrophobic tunnel, specific for aliphatic chains of 16 carbons. Access to the tunnel is controlled by a flexible loop and a gating helix at the protein-membrane interface. Structural and mutagenesis investigations identify a cluster of hydrophilic catalytic residues, including an essential tyrosine, possibly involved in substrate proton abstraction, and the arginine that is mutated in ADPS-deficient patients. We propose that ether bond formation might be orchestrated through a covalent imine intermediate with the flavin, accounting for the noncanonical employment of a flavin cofactor in a nonredox reaction. The crucial step in ether phospholipid biosynthesis: structural basis of a noncanonical reaction associated with a peroxisomal disorder.,Razeto A, Mattiroli F, Carpanelli E, Aliverti A, Pandini V, Coda A, Mattevi A Structure. 2007 Jun;15(6):683-92. PMID:17562315[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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