Structure and organization of genes for transfer ribonucleic acid in Bacillus subtilis.

INTRODUCTION................................................ 71 ORGANIZATION OF tRNA GENE REGIONS ................................................ o 71 Mapping of tRNA and rRNA Gene Clusters ................................................ 71 Large Clusters of tRNA genes-Evolutionary Considerations ................................................ 73 SEQUENCE ANALYSIS OF tRNA STRUCTURAL GENES .................. oooo . -.--......o-o-o-o-o74 Sequences of MaturetRNAs. ........... ..--.---......_74 Sequences of tRNA Structural Genes ..75 Unusual Features of Certain tRNA Structural Genes...........75 tRNA genes containing an A at position32 .......... ......... ...... .......... --75 Extra G at the 5' end of the gene for histidine tRNA........ ..-.-.-............ 75 tRNA with a methionine anticodon might accept isoleucine....... o ............75 tRNA Genes That Do Not Encode the CCA 3' Terminus ...... .........o-75 Gene Copy Number............ . ......... .............. ..........oo76 Which Anticodons Are Represented?....7........................... . . , 76 PUTATIVE TRANSCRIPTIONAL CONTROL ELEMENTS FOR tRNA GENE SETS FROM' B. SUBTILIS .............. .. .. . ............... 77 Promoters. ............... .......... . ............ 77 Sequences Associated with the Stringent Response....................... .............. 78 Termination........................ ....... ....... . 78 Processing Signals ..... o.......-.. 78 SUMMARY ................................... ......... ........ , 78 tRNA genes in B. subtls are highly clustered .... ........... o. 78 tRNA gene clusters do not contain interuaHy repeatedsequences.79 Spacer tRNA genes are found in only a few rRNA gene sets ...... o o o ... .79 tRNA genes are usuafly found in association with rRNA genes ............................................ o...... 79 Most tRNA genes encode the CCA 3' terminus................................ .79 Two large clusters of tRNA genes distal to rRNA gene sets may initiate transcription from within the tRNA genes in addition to being part of the larger rRNA transcriptional unit ...... o ...79 Most tRNA genes have promoter regions including a sequence associated with stringent control........79 ACKNOWLEDGMENTS ................ , , 79 LITERATURE CITED................ . 79