Lotareva O V, Filippov V D
Genetika. 1975;11(12):146-9.
The revertants to adenine prototrophy or mutants to auxotrophy can be easily identified on synthetic media which are partly enriched by caseine hydrolysate and yeast extract. It is shown with the use of these media that 1.5% colonies formed by Bacillus subtilis cells of the original type (ade6 met5) have mutant clones which are initiated by spontaneous revertants to adenine prototrophy. These revertants arise in the time of division of cells in macrocolonies. After plating diluted suspension of irradiated cells those colonies which contain mutant clones formed by spontaneous revertants can be erroneously taken for mixed colonies formed by induced revertants. About 40% mutants to auxotrophy induced by high dose of UV-light in in uvr+ cells form pure mutant colonies. The same mutants, induced by uvr cells by five time less UV-dose, usually form mixed colonies.
在部分添加了酪蛋白水解物和酵母提取物的合成培养基上，可以轻松鉴定出腺嘌呤原养型回复突变体或营养缺陷型突变体。使用这些培养基表明，原始类型（ade6 met5）的枯草芽孢杆菌细胞形成的菌落中有1.5%具有突变克隆，这些克隆由腺嘌呤原养型自发回复突变体引发。这些回复突变体在大菌落中的细胞分裂时出现。在接种经辐照细胞的稀释悬浮液后，那些含有由自发回复突变体形成的突变克隆的菌落可能会被错误地认为是由诱导回复突变体形成的混合菌落。uvr +细胞中高剂量紫外线诱导产生的约40%营养缺陷型突变体形成纯突变菌落。uvr细胞用少五倍的紫外线剂量诱导产生的相同突变体通常形成混合菌落。
