期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1978
卷号:75
期号:6
页码:2649-2653
DOI:10.1073/pnas.75.6.2649
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:A strategy for the proteolytic fragmentation of human IgM has been developed. This method is called "cold pepsin digestion" because of its unique feature of achieving restricted peptic cleavages at 4 degrees and pH 4.0. Cold pepsin digestion has been applied successfully to produce an Fv fragment from 14 human IgM proteins. The Fv fragment consists of the heavy chain variable domain (VH) and the light chain variable domain (VL) held together by strong noncovalent interaction. Thus, each Fv fragment contains one intact antigen-binding site and represents the minimal active fragment derivable from an antibody molecule. A series of other structurally and functionally important fragments were also isolated and characterized. Two basic digestion pathways were recognized; these mainly reflect the relative accessibility of five sets of major interdomain cleavage sites.