Dabbs E R
Mol Gen Genet. 1980;178(2):361-6. doi: 10.1007/BF00270485.
Mutants were isolated from high-level streptomycin dependent strains of Escherichia coli B, which do not spontaneously revert to antibiotic independence. In these mutants the requirement for streptomycin was much reduced, but not abolished. The relieving of the antibiotic dependence was caused by qui (for quasi-independent) mutations. These were analogous to the ramA (rpsD) mutations which relieve the streptomycin requirement of other classes of streptomycin dependent mutants, but strains harboring qui mutations exhibited novel streptomycin phenotypes in conjunction with all rpsL (strA) alleles. RamA mutations increase ribosomal misreading; qui mutations either did not significantly alter misreading, or else reduced it.
突变体是从大肠杆菌B的高水平链霉素依赖菌株中分离出来的，这些菌株不会自发回复到抗生素非依赖状态。在这些突变体中，对链霉素的需求大大降低，但并未消除。抗生素依赖性的缓解是由qui（准独立）突变引起的。这些突变类似于ramA（rpsD）突变，后者可缓解其他类型链霉素依赖突变体对链霉素的需求，但携带qui突变的菌株与所有rpsL（strA）等位基因一起表现出新颖的链霉素表型。RamA突变会增加核糖体错读；qui突变要么不会显著改变错读，要么会降低错读。
