Highly repetitive tRNA(Pro)-tRNA(His) gene cluster from Photobacterium phosphoreum.
A DNA fragment comprising the four tRNA gene sequences of the Escherichia coli argT locus hybridized with two Sau3A-generated DNA fragments from the vibrio Photobacterium phosphoreum (ATCC 11040). Detailed sequence analysis of the longer fragment shows the following gene organization: 5'-promoter-tRNA(Pro)-tRNAPro-tRNA(Pro)-tRNA(His)-tRNA(Pro)-tRNA(Pro)- tRNA(His)-tRNA(Pro)-five pseudogenes derived from the upstream tRNAPro interspersed by putative Rho-independent terminators. This sequence demonstrates the presence of highly repetitive, tandem tRNA genes in a bacterial genome. Furthermore, a stretch of 304 nucleotides from this cluster was found virtually unchanged in the other (shorter) fragment which was previously sequenced. The two clusters together contain eight tRNA(Pro) pseudogenes and eight fully intact tRNA(Pro) genes, an unusually high number for a single eubacterial isoacceptor tRNA. These results show that the organization of some tRNA operons is highly variable in eubacteria.
Giroux
S
S
Département de Biochimie, Université de Montréal, Québec, Canada.
Beaudet
J
J
Cedergren
R
R
D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D010776:Photobacterium / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012345:RNA, Transfer, Amino Acid-Specific / Q000235:genetics*; D012354:RNA, Transfer, His / Q000235:genetics*; D012361:RNA, Transfer, Pro / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D013728:Terminator Regions, Genetic; D014158:Transcription, Genetic
D012345:RNA, Transfer, Amino Acid-Specific; D012354:RNA, Transfer, His; D012361:RNA, Transfer, Pro