Abstract
Rabbit factor H, a regulatory protein of complement, has a blocked N-terminus. After treatment with pyroglutamyl aminopeptidase, its N-terminus could be determined. The C-terminus of rabbit factor H was determined to be tyrosine by carboxypeptidase A treatment. The peptides produced by cyanogen bromide cleavage were purified by gel chromatography, followed by highperformance liquid chromatography. The N-terminal sequences of eight peptides thus purified were analyzed. When the sequence determined in this study was compared with that of mouse factor H derived from the complementary deoxyribonucleic acid (cDNA) sequence, which has recently been reported by Kristensen and Tack, 100 of the 167 residues were identical with those of mouse factor H (about 60% homology).
