Homotropic Cooperative Binding of the First Component of Guinea Pig Complement to Rabbit IgG-Erythrocyte Complexes: A Possible Allosteric Effect*
AUTOR(ES)
Thompson, James J.
RESUMO
Binding of the activated first component of guinea pig complement to immune complexes formed between dinitrophenylated erythrocytes and rabbit IgG antibody to 2,4-dinitrophenylhapten has been studied quantitatively. Cooperative binding was observed; it in volves no interactions between the domains on the erythrocyte surface that bind the activated first component of complement, or between the activated complement molecules in solution. By curve-fitting methods, we find that the data are consistent with an allosteric model, which assumes 10 binding sites per domain, a low allosteric equilibrium constant, and virtually exclusive binding to one of the isomers.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=389511Documentos Relacionados
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