Studies on the lipase of Chromobacterium viscosum. IV. Substrate specificity of a low molecular weight lipase.

Abstract

Substrate specificity of lipase B (low molecular weight) of Chromobacterium viscosum was studied. It was suggested that the apparent substrate specificity for emulsions of single triglyceride was affected by the physical state of the emulsion. At a lower temperature, triglycerides of medium-chain fatty acids were good substrates, while at higher temperatures, triglycerides of long-chain fatty acids became better substrates. It was concluded from the data on hydrolysis of methyl esters of fatty acid and the mixture of a series of single triglyceride that lipase B had a specificity to long-chain and unsaturated fatty acid esters, but the esters of stearic acid were not good substrates. Further, it was suggested that the mixture of a series of single triglycerides was more appropriate than the single substrates for studies on the substrate specificity of lipase. Lipase B was capable of hydrolyzing the fatty acid ester bonds at the 2-position of triglycerides as well as the 1- and 3-positions at the same rate.