Variation of the glycosylation of human pancreatic bile-salt-dependent lipase.
Glycoproteins of human pancreatic juice were characterized by means of lectins after electrophoresis and electrotransfer to nitrocellulose membranes. For the detected glycoproteins, only a 100-kDa glycoprotein varied in the pancreatic juice from a normal patient (i.e. without any pancreatic disorder) compared to the pancreatic juice from a patient suffering from chronic pancreatitis. This protein, which is the only protein in human pancreatic juice which is O-glycosylated and N-glycosylated, was identified as the bile-salt-dependent lipase. Among the glycosylated proteins present in human pancreatic juice, only the glycosylation of bile-salt-dependent lipase differs between individuals. The enzyme was isolated either from normal or pathological human pancreatic juices. The purified variants have an identical molecular mass and amino-acid composition. As suspected from lectin affinity studies, the oligosaccharide composition differs between the variants. The structure of the N-linked oligosaccharides of the variant from the pancreatic juice of a normal donor correlated with complete processing and maturation of a complex-type N-glycan. Alteration of the maturation process can be detected for a bile-salt-dependent-lipase variant from a patient suffering with chronic pancreatitis, since the carbohydrate composition is compatible with the predominance of hybrid or high-mannose-type structures. The amount of sugar involved in O-glycosylation associated with the peanut agglutinin reactivity suggests the presence of 12-14 minimal Gal beta 1-->3GalNac-->T/S O-glycan structures which are sialylated and fucosylated. The amount of sugar involved in the O-linked oligosaccharide structure appears to be unchanged in the variants isolated from the pathological pancreatic juice.
Mas
E
E
INSERM U260, Faculté de Médecine, Marseille, France.
Abouakil
N
N
Roudani
S
S
Franc
J L
JL
Montreuil
J
J
Lombardo
D
D
D001647:Bile Acids and Salts / Q000378:metabolism*; D015153:Blotting, Western; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D006031:Glycosylation; D006801:Humans; D037102:Lectins; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D010189:Pancreatic Juice / Q000201:enzymology*
D001647:Bile Acids and Salts; D002241:Carbohydrates; D037102:Lectins; D008049:Lipase