title: Glycosylated trypsin-like proteases from earthworm Eisenia fetida.
abstract: Although groups of earthworm proteases have been found by several laboratories, it is still unclear how many of the isolated trypsin-like fibrinolytic enzymes are in glycosylated form. Here, eight glycosylated fibrinolytic proteases (EfP-0-1, EfP-0-2, EfP-I-1, EfP-I-2, EfP-II-1, EfP-II-2, EfP-III-1 and EfP-III-2) were isolated from an earthworm species (Eisenia fetida) through a stepwise-purification procedure: ammonium sulfate precipitation, affinity chromatography on a Sepharose-4B column coupled with soybean trypsin inhibitor (SBTI), and ionic chromatography with a DEAE-Cellulose-52 column. Among the eight purified trypsin-like glyco-proteases, EfP-0-2 and EfP-II-2 were newly isolated isozymes. Glycoprotein staining of the proteases on native-PAGE with a Schiff's reagent (sodium meta-periodate) revealed that the eight proteases were glycoproteins. Measurements of the glycan content with sodium meta-periodate and glycoprotein-test reagent showed that these proteases had different carbohydrate contents. Dot-blotting assay with ConA suggested the oligosaccharides were composed of mannose residues.
authors.affiliation: College of Life Science, Hebei University, 180 Wusi East Road, Baoding City 071002, Hebei, China.
authors.forename: Jin Xia
authors.initials: JX
authors.lastname: Wu
authors.forename: Xiao Yu
authors.initials: XY
authors.lastname: Zhao
authors.forename: Rong
authors.initials: R
authors.lastname: Pan
authors.forename: Rong Qiao
authors.initials: RQ
authors.lastname: He
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D050260:Carbohydrate Metabolism; D004789:Enzyme Activation; D005340:Fibrinogen / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism; D006031:Glycosylation; D006868:Hydrolysis; D007527:Isoenzymes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D009835:Oligochaeta / Q000201:enzymology*; D010434:Pepsin A / Q000378:metabolism; D014357:Trypsin / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D006023:Glycoproteins; D007527:Isoenzymes; D005340:Fibrinogen; D014357:Trypsin; D010434:Pepsin A