In vivo studies on yeast cytochrome c methylation in relation to protein synthesis.
Methylation of cytochrome c was studied in vivo using double label with L-[methyl-3H]methionine and DL-[2-14C]methionine. In pulse-chase experiments the cytochrome c associated with the mitochondrial fraction possessed a higher ratio of 3H/14C label, suggesting the presence of methylated cytochrome c. The appearance of methylated cytochrome c in mitochondria showed no lag phase. The inhibition of cytochrome c methylation in presence of cycloheximide indicated that both the methylation and protein synthesis were tightly coupled and cycloheximide selectively inhibited cytochrome c methylation. There was also an indication of selective turnover of incorporation methyl groups in preformed cytochrome c.
D002250:Carbon Radioisotopes; D003513:Cycloheximide / Q000494:pharmacology; D003574:Cytochrome c Group / Q000378:metabolism*; D005656:Fungal Proteins / Q000096:biosynthesis*; D007700:Kinetics; D008715:Methionine / Q000378:metabolism; D008745:Methylation; D008928:Mitochondria / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*; D014316:Tritium
D002250:Carbon Radioisotopes; D003574:Cytochrome c Group; D005656:Fungal Proteins; D014316:Tritium; D003513:Cycloheximide; D008715:Methionine