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A lipase is an enzyme that catalyzes the hydrolysis of fats (lipids). Lipases are a subclass of the esterases. Lipases perform essential roles in the digestion, transport and processing of dietary lipids (e.g. triglycerides, fats, oils) in most, if not all, living organisms. Genes encoding lipases are even present in certain viruses. Most lipases act at a specific position on the glycerol backbone of lipid substrate (A1, A2 or A3)(small intestine). For example, human pancreatic lipase (HPL), which is the main enzyme that breaks down dietary fats in the human digestive system, converts triglyceride substrates found in ingested oils to monoglycerides and two fatty acids. Several other types of lipase activities exist in nature, such as phospholipases and sphingomyelinases, however these are usually treated separately from "conventional" lipases. Some lipases are expressed and secreted by pathogenic organisms during the infection. In particular, ''Candida albicans'' has a large number of different lipases, possibly reflecting broad lipolytic activity, which may contribute to the persistence and virulence of ''C. albicans ''in human tissue. ==Structure and catalytic mechanism== Although a diverse array of genetically distinct lipase enzymes are found in nature, and represent several types of protein folds and catalytic mechanisms, most are built on an alpha/beta hydrolase fold and employ a chymotrypsin-like hydrolysis mechanism using a catalytic triad consisting of a serine nucleophile, a histidine base, and an acid residue (usually aspartic acid). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lipase」の詳細全文を読む スポンサード リンク
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