Bibb M J, Bibb M J, Ward J M, Cohen S N
Mol Gen Genet. 1985;199(1):26-36. doi: 10.1007/BF00327505.
Promoter-probe plasmid vectors were used to isolate putative promoter-containing DNA fragments of three Streptomyces antibiotic resistance genes, the rRNA methylase (tsr) gene of S. azureus, the aminoglycoside phosphotransferase (aph) gene of S. fradiae, and the viomycin phosphotransferase (vph) gene of S. vinaceus. DNA sequence analysis was carried out for all three of the fragments and for the protein-coding regions of the tsr and vph genes. No sequences resembling typical E. coli promoters or Bacillus vegetatively-expressed promoters were identified. Furthermore, none of the three DNA fragments found to be transcriptionally active in Streptomyces could initiate transcription when introduced into E. coli. An extremely biased codon usage pattern that reflects the high G + C composition of Streptomyces DNA was observed for the protein-coding regions of the tsr and vph genes, and of the previously sequenced aph gene. This pattern enabled delineation of the protein-coding region and identification of the coding strand of the genes.
启动子探针质粒载体被用于分离三种链霉菌抗生素抗性基因中假定含启动子的DNA片段，即天蓝链霉菌的rRNA甲基化酶（tsr）基因、弗氏链霉菌的氨基糖苷磷酸转移酶（aph）基因以及酒红色链霉菌的紫霉素磷酸转移酶（vph）基因。对所有这三个片段以及tsr和vph基因的蛋白质编码区进行了DNA序列分析。未鉴定出与典型大肠杆菌启动子或芽孢杆菌营养期表达启动子相似的序列。此外，发现这三个在链霉菌中具有转录活性的DNA片段，当导入大肠杆菌时均无法启动转录。在tsr和vph基因以及先前测序的aph基因的蛋白质编码区，观察到了一种极度偏向的密码子使用模式，这反映了链霉菌DNA的高G + C组成。这种模式有助于划定蛋白质编码区并鉴定基因的编码链。
