Inokuchi H, Kondo K, Yoshimura M, Ozeki H
Department of Biophysics, Faculty of Science, Kyoto University, Japan.
Mol Gen Genet. 1990 Sep;223(3):433-7. doi: 10.1007/BF00264450.
A UGA suppressor derived from a glutamine tRNA gene of Escherichia coli K12 was isolated and characterized. Phages carrying the suppressor su+2UGA could be obtained only from a hybrid transducing phage, h80cI857psu+2oc, but not from the original transducing phage lambda cI857psu+2oc. By DNA sequence analysis, it was found that the su+2 UGA suppressor obtained has two mutations; one is in the anticodon (TTA----TCA), as expected, and the other (C----T) is at the 7th position from the 3' end of tRNA(2Gln). The significance of these mutations and the lethal effect on phage lambda of the increased amounts of UGA suppressor tRNAs are discussed.
从大肠杆菌K12的谷氨酰胺tRNA基因中分离并鉴定出一种UGA抑制子。携带抑制子su + 2UGA的噬菌体只能从杂交转导噬菌体h80cI857psu + 2oc中获得，而不能从原始转导噬菌体λcI857psu + 2oc中获得。通过DNA序列分析发现，所获得的su + 2 UGA抑制子有两个突变；一个如预期在反密码子中（TTA----TCA），另一个（C----T）位于tRNA(2Gln) 3'端的第7位。讨论了这些突变的意义以及UGA抑制子tRNA数量增加对噬菌体λ的致死效应。
