Specificity of diacylglycerol acyltransferase from bovine mammary gland, liver and adipose tissue towards acyl-CoA esters.
1. Microsomal diacylglycerol acyltransferase from bovine lactating mammary gland, liver and adipose tissue was capable of acylating microsomal-bound 1,2-dipalmitolyglycerol with acyl-CoA of chain length C4--C18. 2. The activity of the liver and adipose enzymes towards butyryl-CoA and hexanoyl-CoA relative to longer-chain acyl-CoA was similar to that of the mammary enzyme. The Km and V values of the three enzymes with butyryl-CoA and hexanoyl-CoA were similar, except for the V values of the adipose enzyme which were higher. 3. Microsomal diacylglycerol acyltransferase from mammary gland and liver of non-ruminants was also capable of utilizing butyryl-CoA. 4. These results indicate that the unique presence of short-chain acids in ruminant milk triacylglycerols is not caused by differences in specificity between the diacylglycerol acyltransferase from ruminant mammary and other tissues.
D000214:Acyl Coenzyme A / Q000378:metabolism; D000217:Acyltransferases / Q000378:metabolism*; D000273:Adipose Tissue / Q000201:enzymology*; D000818:Animals; D002417:Cattle; D004075:Diglycerides; D005260:Female; D008099:Liver / Q000201:enzymology*; D008321:Mammary Glands, Animal / Q000201:enzymology*; D008861:Microsomes / Q000201:enzymology; D008970:Molecular Weight; D011817:Rabbits; D013045:Species Specificity; D013379:Substrate Specificity
D000214:Acyl Coenzyme A; D004075:Diglycerides; D000217:Acyltransferases