Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1985-12-4
pubmed:abstractText
The method of principal component analysis (PCA) was applied to the absorption-wavelength-time surfaces generated by rapid scanning stopped-flow spectrophotometry (RSSFS). The method was used to resolve the absorption surfaces generated during the reduction of cytochrome c oxidase by 5,10-dihydro-5-methyl phenazine (MPH) into the individual spectral shapes and time courses of the component chromophores. Two forms of resting cytochrome oxidase were used in these analyses: one that has its maximum absorption in the Soret region at 418 nm (418-nm species) and the other has its absorption maximum at 424 nm (424-nm species). A weighting scheme suitable for RSSFS data was developed. The optical absorption spectra obtained by W.H. Vanneste (1966, Biochemistry, 5:838-848) for the oxidase components were found to fit adequately as components of the experimental surfaces. Among these spectra were the oxidized forms of cytochromes a and a3 in the wavelength region 330-520 nm for the 418-nm species. Vanneste's spectral shape for the oxidized cytochrome a3 did not fit as a component in the spectrum of the 424-nm species. After accounting for the spectral shape of all components present, PCA provided a straightforward method for determining the separate time courses of each chromophore. We have found for both forms used that cytochrome a is reduced by MPH in the initial stages of the reaction, while cytochrome a3 is reduced in subsequent, slow phases. An important aspect of PCA is that it provided confirmation of the spectra of the various oxidase components without requiring the use of inhibitors or the use of simplifying mechanistic assumptions. The resolution of time profiles of strongly overlapping chromophores is also demonstrated.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-13846567, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-14063315, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-182532, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-200223, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-204649, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-228720, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-4287829, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-4354851, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-4364360, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-4375490, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6249819, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6256379, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6260145, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6262822, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6267032, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6268153, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6297540, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6326817, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-6572974, http://linkedlifedata.com/resource/pubmed/commentcorrection/2996647-7056726
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-3495
pubmed:author
pubmed:issnType
Print
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
209-19
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
The use of principal component analysis to resolve the spectra and kinetics of cytochrome c oxidase reduction by 5,10-dihydro-5-methyl phenazine.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.