Cyanogen Bromide Fragments of Human Serum Albumin

作者：Rapier H. McMenamy, Howard M. Dintzis, Frank E. Watson · 发表于：Journal of Biological Chemistry · 年份：1971 · DOI：10.1016/s0021-9258(18)61998-2 · 被引用次数：87 · 研究领域：Protein Interaction Studies and Fluorescence Analysis、Hemoglobin structure and function、Mass Spectrometry Techniques and Applications

Abstract CNBr cleaves nonreduced human serum albumin into three large fragments, A, B, and C, which account for the total amino acid composition of albumin. Reduction and carboxamidomethylation of the free —SH groups produce four subfragments from A, identified according to their NH2-terminal amino acid residues as A-ProI (32 residues), A-AsxI (38 residues), A-ProII (109 residues), and A-Phe (92 residues). A small residue which contains no homoserine is unaccounted for in this sum of the subfragments in A. A-AsxI contains the COOH-terminal leucine of albumin. Reduction and carboxamidomethylation of fragment B produce two further subfragments, B-Ala (36 residues) and B-AspII (89 residues). These subfractions account for all amino acid residues in B. B-AspII contains the NH2-terminal Asp and free —SH group of albumin. Fragment C has only one peptide chain (164 residues) with an NH2-terminal Cys residue. Heterogeneity in disulfide linkages is evident in some preparations.