Synthesis of cytochrome f by isolated pea chloroplasts.
Chloroplasts, isolated from the leaves of 7-day-old pea seedlings, were incubated in the light with [35S]methionine or [3H]leucine. After extraction from the washed chloroplast membranes using a mixture of ethyl acetate, ethanol and ammonia, cytochrome f was precipitated with a monospecific antiserum and resolved by gradient polyacrylamide gel electrophoresis in sodium dodecylsulphate. The cytochrome f band was identified by its intrinsic fluorescence in ultraviolet light and was shown to be radioactive by autoradiography or fluorography of dried polyacrylamide gel. One-dimensional peptide mapping of the products of papain hydrolysis confirmed that the radioactivity was an integral part of cytochrome f. The incorporation of [35S]methionine into cytochrome f was inhibited by D(-)threo-chloramphenicol but not by cycloheximide and did not occur in the dark. The synthesis was resistant to ribonuclease. It is concluded that cytochrome f is synthesised in intact isolated pea chloroplasts.
D002701:Chloramphenicol / Q000494:pharmacology; D002736:Chloroplasts / Q000187:drug effects / Q000378:metabolism*; D003513:Cycloheximide / Q000494:pharmacology; D003580:Cytochromes / Q000096:biosynthesis*; D007930:Leucine / Q000378:metabolism; D008027:Light; D008715:Methionine / Q000378:metabolism; D010446:Peptide Fragments / Q000032:analysis; D010944:Plants / Q000378:metabolism
D003580:Cytochromes; D010446:Peptide Fragments; D002701:Chloramphenicol; D003513:Cycloheximide; D008715:Methionine; D007930:Leucine