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2uuu
From Proteopedia
ALKYLDIHYDROXYACETONEPHOSPHATE SYNTHASE IN P212121
Overview
Ether 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.
About this Structure
2UUU is a Single protein structure of sequence from Dictyostelium discoideum. Full crystallographic information is available from OCA.
Reference
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 Page seeded by OCA on Sun May 4 17:31:47 2008
Categories: Alkylglycerone-phosphate synthase | Dictyostelium discoideum | Single protein | Aliverti, A. | Carpanelli, E. | Coda, A. | Mattevi, A. | Mattiroli, F. | Pandini, V. | Razeto, A. | Biosynthesis of phospholipid | Fad | Flavin | Flavoprotein | Lipid synthesis | Peroxisomal disorder | Peroxisome | Plasmalogen | Rhizomelic chondrodysplasia punctata | Transferase
