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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1981-4-13
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pubmed:abstractText |
Heme a was not detected either in mitochondria isolated from copper-deficient yeast or in the intact cells. Nevertheless, the intracellular concentration of free porphyrins indicated that the pathway of porphyrin and heme synthesis was not impaired in copper-deficient cells. The immunoprecipitated apo-oxidase from copper-deficient cells revealed an absorption spectrum with maxima at 645, 592, 559, 519 and 423 nm, similar to that of purified porphyrin a. When solubilized mitochondria from [3H]leucine and delta-amino[14C]levulinic acid-labeled copper-deficient yeast cells were incubated with rabbit antiserum against cytochrome c oxidase, a precipitate was obtained. Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of this immunoprecipitate showed [3H]leucine associated with six bands and delta-amino[14C]levulinic acid resolved in a single band. HCl fractionation of copper-deficient mitochondria labeled with delta amino[14C]levulinic acid showed a high specific radioactivity in the fraction extracted by 20% HCl, a solvent which extracts porphyrin a. Thin-layer chromatography of the radioactivity found in 20% HCl showed an RF value identical to that of purified porphyrin a. When delta-amino[3H]levulinic acid-labeled, copper-deficient yeast cells are grown in copper-supplemented medium, the porphyrin a accumulated in copper-deficient cells was converted into heme a, and this conversion was prevented by cycloheximidine. These observations suggest that porphyrin a is present in the apo-oxidase of copper-deficient cells, but that the conversion to heme a does not occur. This conversion reaction appears to be a point in the biosynthetic pathway of cytochrome c oxidase which is blocked by copper deficiency.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Aminolevulinic Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Apoenzymes,
http://linkedlifedata.com/resource/pubmed/chemical/Apoproteins,
http://linkedlifedata.com/resource/pubmed/chemical/Copper,
http://linkedlifedata.com/resource/pubmed/chemical/Electron Transport Complex IV,
http://linkedlifedata.com/resource/pubmed/chemical/Heme,
http://linkedlifedata.com/resource/pubmed/chemical/Porphyrins,
http://linkedlifedata.com/resource/pubmed/chemical/heme a
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pubmed:status |
MEDLINE
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pubmed:month |
Dec
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pubmed:issn |
0006-3002
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
1
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pubmed:volume |
633
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
211-27
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:6257308-Aminolevulinic Acid,
pubmed-meshheading:6257308-Apoenzymes,
pubmed-meshheading:6257308-Apoproteins,
pubmed-meshheading:6257308-Chromatography, Thin Layer,
pubmed-meshheading:6257308-Copper,
pubmed-meshheading:6257308-Electron Transport Complex IV,
pubmed-meshheading:6257308-Electrophoresis, Polyacrylamide Gel,
pubmed-meshheading:6257308-Heme,
pubmed-meshheading:6257308-Mitochondria,
pubmed-meshheading:6257308-Molecular Weight,
pubmed-meshheading:6257308-Porphyrins,
pubmed-meshheading:6257308-Saccharomyces cerevisiae,
pubmed-meshheading:6257308-Spectrophotometry
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pubmed:year |
1980
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pubmed:articleTitle |
Identification of porphyrin present in apo-cytochrome C oxidase of copper-deficient yeast cells.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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