The effect of fatty acid chain length on the rate of arylester hydrolysis by various albumins.
A series of synthetic chromogenic and fluorogenic substrates for monitoring the arylesterase-like activity of albumins from various sources has been studied. Except for ovalbumin, all displayed enzyme-like activity. The acetate, butyrate, caprylate, laurate, and palmitate esters of a coumarin dye were found to be efficiently hydrolyzed within the pH range 8.8-9.8, with the non-enzymatic rate being highest for acetate and lowest for laurate. The latter is considered to be the substrate of choice because it is cleaved most quickly by the proteins tested. A considerable increase in hydrolytic activity was observed upon addition of detergents, but not of Ca and Mg ions, while addition of 1 equivalent of lauric acid to BSA resulted in a 30% decrease in its activity. The results are interpreted in terms of the well-known affinity of albumins for long chain fatty acids and provide the basis for a sensitive determination of small amounts of albumins.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002264:Carboxylic Acids / Q000097:blood*; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology; D004952:Esters / Q000097:blood*; D005227:Fatty Acids / Q000097:blood*; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D012709:Serum Albumin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013379:Substrate Specificity
D002264:Carboxylic Acids; D002593:Cetrimonium Compounds; D004952:Esters; D005227:Fatty Acids; D012709:Serum Albumin; D008274:Magnesium; D002118:Calcium; D000077286:Cetrimonium