Isolation and partial characterization of the messenger RNA encoding the B880 holochrome protein of Rhodospirillum rubrum.
The B880 holochrome messenger RNA was extracted from cultures of the photosynthetic bacterium Rhodospirillum rubrum. It was purified by chromatography on Sepharose 4B followed by sucrose density gradient centrifugation. The purified fractions were shown to program an Escherichia coli cell-free system into synthesizing both the alpha and the beta polypeptides of the holochrome. The translation products were identified by immunoprecipitation with specific antibodies raised against these polypeptides. The latter are effective competitors with the translation products for antigen-antibody complex formation. The purest mRNA preparations contained approximately 33% holochrome messenger RNA activity. Its most probable size, as determined by agarose gel electrophoresis in the presence of 6 M urea or methylmercuric hydroxide, is approximately 620 nucleotides. Since the combined sizes of the alpha and beta polypeptides add up to only 106 amino acid residues, we conclude that the holochrome mRNA is most probably polycistronic.
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D001426:Bacterial Proteins; D002499:Centrifugation, Density Gradient; D011232:Chemical Precipitation; D002734:Chlorophyll / Q000031:analogs & derivatives*; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D007120:Immunochemistry; D010777:Photochemistry; D010779:Photofluorography; D010940:Plant Proteins / Q000235:genetics*; D014176:Protein Biosynthesis; D011521:Protochlorophyllide / Q000235:genetics*; D012329:RNA, Bacterial / Q000302:isolation & purification*; D012333:RNA, Messenger / Q000302:isolation & purification*; D012247:Rhodospirillum rubrum / Q000235:genetics*
D001426:Bacterial Proteins; D010940:Plant Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; C001348:holochrome protein, Rhodospirillum rubrum; D002734:Chlorophyll; D011521:Protochlorophyllide