Linked Life Data

9986

Source:http://linkedlifedata.com/resource/pubmed/id/9986

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1976-12-30
pubmed:abstractText
The oxidation-reduction potential of chloroperoxidase, an enzyme which catalyzes peroxidative chlorination, bromination, and iodination reactions, has been investigated. In addition to catalyzing biological halogenation reactions, chloroperoxidase is unusual in that the carbon monoxide complex of ferrous chloroperoxidase shows the typical long wavelength Soret absorption associated with P-450 hemoproteins. The pH dependence of the chloroperoxidase oxidation-reduction potential shows a discontinuity around pH 4.7. Similarly, measurements of the affinity of ferrous chloroperoxidase for carbon monoxide monitored both by spectroscopic and potentiometric titration exhibit a discontinuity in the pH 4.7 region. Oxidation-reduction potential measurements on chloroperoxidase in a CO atmosphere also show a discontinuous pH profile. These results suggest that ferrous chloroperoxidase undergoes reversible modification at low pH and that these changes are reflected in the oxidation-reduction potential. The oxidation-reduction potential of chloroperoxidase at pH 6.9 is - 140 mV, close to that measured for cytochrome P-450cam in the presence of substrate. The oxidation-reduction potential of chloroperoxidase at pH 2.7, the pH optimum for enzymatic chlorination, is +150 mV. The oxidation-reduction potentials of the halide complexes of chloroperoxidase (chloride, bromide, and iodide) are essentially identical with the potential measurements on the native enzyme. These observations suggest that, although halide anions bind to the enzyme, they probably do not bind as an axial ligand to the heme ferric iron.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4748-54
pubmed:dateRevised
2009-10-27
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Oxidation-reduction potential measurements on chloroperoxidase and its complexes.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.