Linked Life Data

8499447

Source:http://linkedlifedata.com/resource/pubmed/id/8499447

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1993-6-29
pubmed:abstractText
The reaction between reduced cytochrome bo from Escherichia coli and oxygen has been studied using flash photolysis of the CO complex of the reduced protein after rapid mixing with oxygen. Absorbance changes were monitored in the alpha and Soret spectral regions. Two kinetic phases taking place at catalytically competent rates could be detected. The apparent rate constant obtained for both the first and second phase showed a hyperbolic dependence on the oxygen concentration. For the first phase, we obtained limiting first- and second-order rate constants at saturating and low oxygen concentrations of 4.5 x 10(4) s-1 and 1.6 x 10(8) M-1 s-1, respectively. The corresponding values for the second phase were 5 x 10(3) s-1 and 1.7 x 10(7) M-1 s-1. The first phase accounted for 30% of the total absorbance change in the Soret band (430 nm) and 15% of the total absorbance change in the alpha band (555 nm). These reactions are followed by a very slow phase with a lifetime of about 1 s. We have also studied the interaction between the fully oxidized enzyme and hydrogen peroxide, and we have found that peroxide binding induces an absorbance increase in the alpha band and a red shift of the Soret band. A consideration of the magnitude of the absorbance changes taking place during the first phase suggests that this reaction includes at least partial oxidation of the low-spin cytochrome b.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5442-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Flow-flash study of the reaction between cytochrome bo and oxygen.
pubmed:affiliation
Department of Biochemistry and Biophysics, Chalmers University of Technology, Göteborg, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't