PORCINE FIBRINOGEN GLYCOPEPTIDES - SUBSTRATES FOR DETECTING ENDO-BETA-N-ACETYLGLUCOSAMINIDASES F2 AND F3

Two different glycopeptides were isolated in high yield from a thermol ytic digest of porcine fibrinogen, Edman analysis established their se quences as Val-Gly-Asn(CHO)-Lys and Val-Gly-Glu-Asn(CHO)-Arg. These se quences are nearly identical to the two human fibrinogen glycopeptides , Val-Glu-Asn(CHO)-Lys (gamma-chain), and Met-Gly-Glu-Asn(CHO)-Arg (be ta-chain). The predominant carbohydrate moiety of both asialoglycopept ides was a biantennary oligosaccharide with a core alpha(1 --> 6)-link ed fucose as reported earlier (Da Silva et al. (1994) Arch. Biochem. B iophys. 312, 151-157). Both glycopeptides can be dansylated and used a s sensitive substrates for Flavobacterium meningo septicum endo-beta-N -acetylglucosaminidases F-2 and F-3. Porcine fibrinogen represents the best source for substrates with this oligosaccharide type that can be reliably produced in multimicromole quantities. (C) 1996 Academic Pre ss, Inc.