Amino acid sequence of the Bb fragment from human complement Factor B. Alignment of the cyanogen bromide-cleavage peptides.

The alignment of all the CNBr-cleavage peptides of fragment Bb from human Factor B (a component of the alternative pathway of complement) was determined. This was derived from cleavage of the fragment Bb at arginine residues by using trypsin and clostripain. Details of the isolation and amino acid sequences of these peptides are given. Together with previously published N-terminal sequences of the CNBr-cleavage peptides [Christie & Gagnon (1982) Biochem. J. 201, 555-567], this provides the amino acid sequence of the N-terminal half of fragment Bb.