Pancreatic Cholesteryl Esterase in Health and Disease
Pancreatic cholesterol esterase, also called carboxyl ester lipase or bile salt-dependent lipase (BSDL, E. C. 3. 1. 1.13), catalyzes the hydrolysis of ester substrates as well as some phospholipids and lysophospholipids. In addition, the bile salt-dependent lipase is the unique enzyme in the pancreatic juice capable of hydrolyzing fat-soluble-vitamins and cholesteryl esters. This latter function strongly suggests that BSDL is important for catalyzing the lymphatic absorption of dietary cholesterol and fat-soluble vitamins. BSDL from the rat, dog, pig, bovine and human pancreas has been purified to homogeneity. The molecular mass differs significantly among species: human BSDL 100 kDa; dog 87–93 kDa; pig 80–90 kDa; bovine BSDL occurs predominantly as a 72 kDa protein; and that of the rat is 67 kDa. Recently, the full-length cDNA of pancreatic BSDL from different species has been cloned and sequenced[4–6]. Jacobson et al. have reported that rat BSDL is a glycosylated protein which contains a potential N-linked glycosylation site at Asn at position 187, [4–6], this site is conserved in the bovine and human protein. The sugar composition of the human pancreatic BSDL agrees with the presence one N-linked oligosaccharide of complex or hybrid type and of 0-linked oligosaccharides. The transfer en bloc of the precursor dolichol-pyrophosphate oligomannoside is essential for the setting up of the active conformation and secretion of the enzyme. The trimming and the processing of the highmannose structure does not affect either the enzyme activity or its secretion.
KeywordsAcute Pancreatitis Pancreatic Juice Human Pancreas Pancreatic Pathology Benign Liver Disease
Unable to display preview. Download preview PDF.
- 9.N. Abouakil, E. Mas, N. Bruneau, A. Benajiba, and D. Lombardo, Bile-Salt Dependent Lipase Biosynthesis in Rat Pancreatic AR 4-2 J Cells: Essential requirement of N-linked oligosaccharide for secretion and expression of a fully active enzyme. J. Biol. Chem. in pressGoogle Scholar
- 13.T. Sugo, E. Mas, N.Abouakil, T. Endo, M.J. Escribano, A. Kobata, and D. Lombardo, The Structure of N-linked Oligosaccharides of Human Pancreatic Bile-salt Dependent Lipase. Eur. J. Biochem. in pressGoogle Scholar
- 14.E. Mas, N.Abouakil, S. Roudani, J-L. Franc, J. Montreuil and D. Lombardo, Variation of the Glycosylation of Human Pancreatic Bile-salt Dependent Lipase. Eur. J. Biochem. in pressGoogle Scholar