CGI-58/ABHD5 is a coenzyme A-dependent lysophosphatidic acid acyltransferase.
Mutations in human CGI-58/ABHD5 cause Chanarin-Dorfman syndrome (CDS), characterized by excessive storage of triacylglycerol in tissues. CGI-58 is an alpha/beta-hydrolase fold enzyme expressed in all vertebrates. The carboxyl terminus includes a highly conserved consensus sequence (HXXXXD) for acyltransferase activity. Mouse CGI-58 was expressed in Escherichia coli as a fusion protein with two amino terminal 6-histidine tags. Recombinant CGI-58 displayed acyl-CoA-dependent acyltransferase activity to lysophosphatidic acid, but not to other lysophospholipid or neutral glycerolipid acceptors. Production of phosphatidic acid increased with time and increasing concentrations of recombinant CGI-58 and was optimal between pH 7.0 and 8.5. The enzyme showed saturation kinetics with respect to 1-oleoyl-lysophosphatidic acid and oleoyl-CoA and preference for arachidonoyl-CoA and oleoyl-CoA. The enzyme showed slight preference for 1-oleoyl lysophosphatidic acid over 1-palmitoyl, 1-stearoyl, or 1-arachidonoyl lysophosphatidic acid. Recombinant CGI-58 showed intrinsic fluorescence for tryptophan that was quenched by the addition of 1-oleoyl-lysophosphatidic acid, oleoyl-CoA, arachidonoyl-CoA, and palmitoyl-CoA, but not by lysophosphatidyl choline. Expression of CGI-58 in fibroblasts from humans with CDS increased the incorporation of radiolabeled fatty acids released from the lipolysis of stored triacylglycerols into phospholipids. CGI-58 is a CoA-dependent lysophosphatidic acid acyltransferase that channels fatty acids released from the hydrolysis of stored triacylglycerols into phospholipids.
Rutgers Center for Lipid Research, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
Gabriela
G
Montero-Moran
Jorge M
JM
Caviglia
Derek
D
McMahon
Alexis
A
Rothenberg
Vidya
V
Subramanian
Zhi
Z
Xu
Samuel
S
Lara-Gonzalez
Judith
J
Storch
George M
GM
Carman
Dawn L
DL
Brasaemle
D051103:1-Acylglycerol-3-Phosphate O-Acyltransferase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000214:Acyl Coenzyme A / Q000378:metabolism*; D000217:Acyltransferases / Q000378:metabolism*; D020816:Amino Acid Motifs; D000818:Animals; D002478:Cells, Cultured; D015870:Gene Expression; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D050356:Lipid Metabolism / Q000235:genetics; D008052:Lipid Metabolism, Inborn Errors / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D008246:Lysophospholipids / Q000378:metabolism*; D051379:Mice; D056510:Position-Specific Scoring Matrices; D011485:Protein Binding; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity; D013577:Syndrome
D000214:Acyl Coenzyme A; D008246:Lysophospholipids; D011994:Recombinant Proteins; D000217:Acyltransferases; D051103:1-Acylglycerol-3-Phosphate O-Acyltransferase; C439972:ABHD5 protein, human; C492986:Abhd5 protein, mouse; C018764:2-acylglycerophosphate acyltransferase