ORGANIZATION AND NUCLEOTIDE-SEQUENCES OF 10 RIBOSOMAL-PROTEIN GENES FROM THE REGION EQUIVALENT TO THE S10 OPERON IN THE ARCHAEBACTERIUM, HALOBACTERIUM-HALOBIUM

A determination was made of the nucleotide sequence of the 7340-bp reg ion of a ribosomal protein gene cluster of Halobacterium halobium, whi ch is equivalent to the S10 operon of Escherichia coli. The sequence w as analyzed with the codonpreference program deduced from the halobact erial codon usage table that showed a very high GC content of the thir d codon position. The sequence was comprised of a string of 13 tightly linked ORFs. Most of the ORFs were homologous with ribosomal protein genes 23-rpl2-rps19-rpl22-rps3-rpl29-ORF11-rps17-rpl14). The 13-gene s tring was preceded by three putative AT-rich promoter sequences. The o rder of the genes in H. halobium essentially agreed with that of the c orresponding genes of E. coli (S10-operon), except for certain deletio ns or insertions of additional protein genes.