Henkin T M, Campbell K M, Chambliss G H
Mol Gen Genet. 1982;186(3):347-54. doi: 10.1007/BF00729453.
Revertants of a streptomycin-resistant (Strr), oligosporogenous (Spo-) mutant of Bacillus subtilis were selected form the ability to sporulate. The revertants obtained fell into two phenotypic classes: Strs Spo+ (streptomycin-sensitive, sporeforming), which arose by reversion of the streptomycin resistance mutations of the parent strain; and Strr Spo+, which arose by the acquisition of additional mutations, some of which were shown to affect ribosomal proteins. Alterations of ribosomal proteins S4 and S16 in the 30S subunit and L18 inthe 50S subunit were detected in Strr Spo+ revertants by polyacrylamide gel electrophoresis. Streptomycin resistance of the parental strain and the Strr revertants was demonstrated to reside in the 30S ribosomal subunit. The second site mutations of the revertants depressed the level of streptomycin resistance in vivo and in the in vitro translation of phage SP01 messenger ribonucleic acid (mRNA) relative to the resistance exhibited by the Strr parental strain. The Strr parent grew slowly and sporulated at approximately 1% of the wild type level. The Strr revertants closely resembled the wild type strain with regard to growth and sporulation. The Strr revertants grew at rates intermediate between those of the Strr patent and wild type, and sporulated at wild type levels.
从枯草芽孢杆菌链霉素抗性（Strr）、寡孢子形成（Spo-）突变体的回复突变体中筛选出能够形成芽孢的菌株。获得的回复突变体分为两个表型类别：Strs Spo+（链霉素敏感、产芽孢），它是由亲本菌株的链霉素抗性突变回复产生的；以及Strr Spo+，它是通过获得额外的突变产生的，其中一些突变被证明会影响核糖体蛋白。通过聚丙烯酰胺凝胶电泳在Strr Spo+回复突变体中检测到30S亚基中的核糖体蛋白S4和S16以及50S亚基中的L18发生了改变。亲本菌株和Strr回复突变体的链霉素抗性被证明存在于30S核糖体亚基中。回复突变体的第二位点突变相对于Strr亲本菌株所表现出的抗性，在体内和噬菌体SP01信使核糖核酸（mRNA）的体外翻译中降低了链霉素抗性水平。Strr亲本生长缓慢，产芽孢率约为野生型水平的1%。Strr回复突变体在生长和产芽孢方面与野生型菌株非常相似。Strr回复突变体的生长速度介于Strr亲本和野生型之间，产芽孢水平与野生型相同。
