Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1984-7-16
pubmed:abstractText
Photodissociation of oxygen from the ferrous subunits of hybrid hemoglobins in which the heme of either the alpha or the beta chain has been replaced by cobalt protoporphyrin IX shows large differences between the subunits. With a 25-ns light pulse, the apparent quantum yield at the end of the flash is greater for the beta-iron hybrid than for the alpha-iron hybrid. With the beta-iron hybrid, the yield is greater when solution conditions favor the T-state. After the flash, a part of the oxygen which has been dissociated recombines with a half-time of the order of tens of nanoseconds. The proportion is greatest in the R-state at low temperature and least in the T-state. With the alpha-iron hybrid, oxygen is much less readily removed, and the rapid recombination is slight or absent. It is seen most clearly at low temperatures in conditions which favor the T-state. The long term (greater than 100 ns) effect is that oxygen is much more readily removed from the beta-iron hybrid in the T-state than under any other condition. Analogous flash experiments performed with human hemoglobin A may be closely simulated by superposition of the results obtained with the two hybrid hemoglobins under the same conditions. Isolated human alpha and beta--SH chains show differences similar to, but less marked than, those of the iron-cobalt hybrids.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6701-3
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Geminate combination of oxygen with iron-cobalt hybrid hemoglobins.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.