A continuous fluorescence assay for lecithin cholesterol acyltransferase

✍ Scribed by Frank S. Bonelli; Katherine E. Kézdy; Ana Jonas

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 288 KB
• Volume: 166
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(87)90564-1

✦ Synopsis

A continuous fluorescence assay was adapted to the measurement of the phospholipase reaction of lecithin cholesterol acyltransferase (LCAT). The fluorescent phospholipid I-acyl-2-(N-4-nitrobenzo-2-oxa-I .3-diazole)aminocaproyl phosphatidylcholine (C,-NBD-PC) in micelle form reacted with LCAT to yield NBD-caproic acid. resulting in up to 5-fold increases in fluorescence in 30 min. The reaction rates were optimal in mixtures containing 0.1 M NaCl and 4 mM @-mercaptoethanol at 37°C. Apolipoprotein A-I did not activate the enzyme and bovine serum albumin bound monomeric substrate and interfered with the fluorescence assay. Under similar reaction conditions, bee venom phospholipase AZ was almost IOO-fold more reactive than LCAT. &z 1987 Acadrmlc PESS, hc.