Open AccesscDNA cloning of human‐milk bile‐salt‐stimulated lipase and evidence for its identity to pancreatic carboxylic ester hydrolase
Author(s) -
NILSSON Jeanette,
BLÄCKBERG Lars,
CARLSSON Peter,
ENERBÄCK Seven,
HERNELL Olle,
BJURSELL Gunnar
Publication year - 1990
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1990.tb19259.x
Subject(s) - lipase , biochemistry , complementary dna , hydrolase , esterase , biology , peptide sequence , triacylglycerol lipase , microbiology and biotechnology , open reading frame , carboxylesterase , catalytic triad , amino acid , monoacylglycerol lipase , cdna library , serine , enzyme , gene , endocannabinoid system , receptor
We have isolated and sequenced cDNA clones covering the entire coding sequence of human‐milk bile‐salt‐stimulated lipase, as well as 996 nucleotides of the 3′ end of the pancreatic enzyme carboxylic ester hydrolase. The deduced amino acid sequence of the lipase starts with a 23‐residue leader peptide. The open reading frame continues with 722 amino acid residues. The sequence contains in the C‐terminal part a proline‐rich repeat, 16 repeats of 11 amino acid residues each. The mRNA was estimated to be approximately 2500 nucleotides from Northern blot and of similar size in mammary and pancreatic tissues. Data obtained indicate that the lipase and the carboxylesterase are identical and coded for by the same gene. The cDNA is 2428 bases long, which indicates that a near full‐length copy of the transcript has been isolated. Comparisons with other enzymes show that the lipase is a new member of the supergene family of serine hydrolases. It is not only closely related (and in its N‐terminal half virtually identical) to lysophospholipase from rat pancreas and cholesterol esterase from bovine pancreas, but also shows a high degree of similarity to several esterases, e.g. acetylcholine esterase. In contrast, no such similarity could be found to typical lipases.