Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1991-3-20
pubmed:abstractText
The binding of carbon dioxide to human hemoglobin cross-linked between Lys alpha 99 residues with bis(3,5-di-bromosalicyl) fumarate was measured using manometric techniques. The binding of CO2 to unmodified hemoglobin can be described by two classes of sites with high and low affinities corresponding to the amino-terminal valines of the beta and alpha chains, respectively (Perrella, M., Kilmartin, J. V., Fogg, J., and Rossi-Bernardi, L. (1975b) Nature 256, 759-761. The cross-linked hemoglobin bound less CO2 than native hemoglobin at all CO2 concentrations in deoxygenated and liganded conformations, and the ligand-linked effect was reduced. Fitting the data to models of CO2 binding suggests that only half of the expected saturation with CO2 is possible. The remaining binding is described by a single affinity constant that for cross-linked deoxyhemoglobin is about two-thirds of the high affinity constant for deoxyhemoglobin A and that for cross-linked cyanomethemoglobin is equal to the high affinity constant for unmodified cyanomethemoglobin A or carbonmonoxyhemoglobin A. The low affinity binding constant for cross-linked hemoglobin in both the deoxygenated and liganded conformations is close to zero, which is significantly less than the affinity constants for either subunit binding site in unmodified hemoglobin. Comparing the low affinity sites in this modified hemoglobin to native hemoglobin suggests that cross-linking hemoglobin between Lys alpha 99 residues prevents CO2 binding at the alpha-subunit NH2 termini.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2697-700
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Carbon dioxide binding to human hemoglobin cross-linked between the alpha chains.
pubmed:affiliation
Division of Blood Research, Letterman Army Institute of Research, Presidio of San Francisco, California 94129-6800.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.