HPLC profile of lysylendopeptidase digests of Bβ-chain. The lysylendopeptidase digests of PE-Bβ chains derived from normal fibrinogen and fibrinogen Niigata were injected on to a Cosmosil 5C18P column (4.6 × 150 nm), and the peptides were eluted with a linear gradient from 0% to 40% acetonitril in 100 minutes. Three peaks, Niigata K47 (*), Niigata K49 (**), and normal K48 (**), were collected and subjected to N-terminal amino acid sequence analysis.