title: Isolation and characterization of a trypsin inhibitor from the seeds of kohlrabi (Brassica napus var. rapifera) belonging to the napin family of storage proteins.
abstract: A trypsin inhibitor with a Km of 5 x 10(-5) M has been isolated from kohlrabi (Brassica napus var. rapifera). Subtilisin DY is inhibited only weakly and chymotrypsin not at all. The inhibitor is closely related to napin as determined by amino acid sequence analysis which also showed the inhibitor to be polymorphous. The inhibitor has been further characterized by means of molecular weight determination using SDS gel-electrophoresis and by amino acid analysis, fluorimetry as well as circular dichroism. A simplified method for purification of napins is given.
authors.affiliation: Department of Chemistry, Carlsberg Laboratory, Copenhagen Valby.
authors.forename: I B
authors.initials: IB
authors.lastname: Svendsen
authors.forename: D
authors.initials: D
authors.lastname: Nicolova
authors.forename: I
authors.initials: I
authors.lastname: Goshev
authors.forename: N
authors.initials: N
authors.lastname: Genov
mesh_terms: D055516:2S Albumins, Plant; D000595:Amino Acid Sequence; D001937:Brassica / Q000201:enzymology*; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D013381:Subtilisins / Q000037:antagonists & inhibitors; D014361:Trypsin Inhibitors / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D055516:2S Albumins, Plant; D010940:Plant Proteins; D014361:Trypsin Inhibitors; C050363:napin protein, Brassica napus; C069599:trypsin inhibitor protein, Brassica napus; D013381:Subtilisins; D002918:Chymotrypsin