Linked Life Data

3742644

Source:http://linkedlifedata.com/resource/pubmed/id/3742644

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1986-10-3
pubmed:abstractText
The spectral interaction of a homologous series of alkyl-substituted benzenes and related compounds with purified mammalian cytochrome P-450 has been investigated. Each of the 10 hydrocarbons produced a Type I spectral change, indicative of a low to high spin transition of the haem iron of cytochrome P-450. The extent of perturbation of the cytochrome P-450 spin equilibrium varied for each compound and was used to quantify the spin shifts of the haemoprotein and consequently the substrate-bound spin equilibrium constant, K2. Molecular orbital calculations were utilised to determine the electronic structural parameters of the 10 hydrocarbons investigated, including the electrophilic and nucleophilic super-delocalizabilities summed over all atoms (sigma SE and sigma SN, respectively), the sum of the absolute values of net atomic charge (sigma QT) and the energy levels of both the highest occupied and lowest unoccupied molecular orbitals (E (HOMO) and E (LUMO) respectively). Multiple regression analyses were then utilized to generate quantitative structure-activity relationships between the above structural parameters and the substrate-bound spin equilibrium constant, K2. Good correlations were observed between sigma SE, sigma SN and sigma QT, indicating the importance of hydrophobicity and steric factors in the perturbation of the haemoprotein spin equilibrium. In addition, the electron-accepting potential of the hydrocarbons was an important structural feature and exhibited better correlations with K2 than the electron donating parameter. Taken collectively, our data show the importance of the hydrophobic and charge transfer characteristics of hydrocarbon substrates in dictating the position of the cytochrome P-450 spin equilibrium, and as such, provides a rational molecular explanation based on sound chemical principles for the differential interaction of hydrocarbons with cytochrome P-450.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0009-2797
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
289-99
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
The interaction of a homologous series of hydrocarbons with hepatic cytochrome P-450. Molecular orbital-derived electronic and structural parameters influencing the haemoprotein spin state.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't