Open AccessFunctional Properties of Human Hemoglobin and Isolated Hemoglobin Chains Treated with Organic Mercurials
Author(s) -
Giardina Bruno,
Binotti Ines,
Amiconi Gino,
Antonini Eraldo,
Brunori Maurizio,
Mcmurray Cecil H.
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb01548.x
Subject(s) - hemoglobin , bohr effect , chemistry , oxygen , dissociation (chemistry) , oxygen–haemoglobin dissociation curve , dissociation constant , stereochemistry , biochemistry , organic chemistry , receptor
The functional properties of human hemoglobin and of isolated α‐ and β‐chains with free SH groups blocked by 2‐chloromercuri‐4‐nitrophenol, 4‐chloromercuri‐2‐nitrophenol and p ‐chloromercuribenzoate have been determined. The oxygen affinity of all the hemoglobin derivatives is slightly higher than that of the untreated protein; the shape of the oxygen equilibrium curve is pH dependent (except for p ‐chloromercuribenzoate reacted hemoglobin). The alkaline Bohr effect is similar to that of normal hemoglobin, but in the acid range it appears to be modified to a different extent in the various cases. Thus the properties of the modified hemoglobins appear to depend on the details of structure of the organic mercurial reacted with the β 93 ‐SH group. The results with isolated β‐chains show that the presence of the organic mercurials on F9(93), but not on G14(112) is associated with a decrease in oxygen affinity and a large increase in the oxygen dissociation velocity constant.