PHYLOGENY OF THE 5S RIBOSOMAL-RNA FROM SYNECHOCOCCUS-LIVIDUS-II - THE CYANOBACTERIAL CHLOROPLAST 5S RNAS FORM A COMMON STRUCTURAL CLASS

The complete nucleotide sequence of the 5S ribosomal RNA from the cyanobacterium S. lividus II was determined. The sequence is 5''-UGCCUAGUGGUUUAUGGCGCGGUGGAACCACGCUGAUCCAUCCCGAACUCAGAGGUGAAACAUCGCAGCGGUGAAGAUAGUUGGAGGGUAGCCUCCUGCAAAAAUAGCUCAAUGCUAGGCAOH-3''. This 5S RNA had the cyanobacterial- and chloroplast-specific nucleotide insertion between positions 30 and 31 (using the numbering system of the generalized eubacterial 5S RNA) and the chloroplast-specific nucleotide-deletion signature between positions 34 and 39. The 5S RNA of S. lividus II has 27 base differences compared with the 5S RNA of the related strain S. lividus III. This large difference may reflect an ancient divergence between these 2 organisms. The electrophoretic mobilities on nondenaturing polyacrylamide gels of renatured 5S RNA from S. lividus II, S. lividus III, and spinach chloroplasts are identical, but differ considerably from that of Escherichia coli 5S RNA. This most likely reflects differences in higher-order structure between the 5S RNA of E. coli and these cyanobacterial and chloroplast 5S RNA.