[Ala214,38] Aprotinin: Preparation by Partial Desulphurization of Aprotinin by Means of Raney Nickel and Comparison with Other Aprotinin Derivatives

Abstract

Treatment of aprotinin with Raney nickel in the presence or absence of denaturants yielded .**GRAPHIC**. Aprotinin and .**GRAPHIC**. aprotinin were separated by ion exchange chromatography at pH 8 using Cm-Sepharose, fast flow. .**GRAPHIC**. aprotinin is a proteinase inhibitor, but it possesses lower affinities than aprotinin, for the enzymes trypsin, .alpha.-chymotrypsin, pancreatic kallikrein and plasmin as reflected by higher Ki values .**GRAPHIC**. aprotinin is slowly degraded by trypsin. The optical activity of .**GRAPHIC**. aprotininin different solvents is quite similar to that of aprotinin, or that of its hydrolysis products, [seco-15/16]aprotinin or [di-seco-15/16,39/40]-aprotinin. This is taken as good evidence for analogous molecular conformations of all these substrates.