CONDITIONAL MUTATOR GENE IN ESCHERICHIA-COLI - ISOLATION, MAPPING, AND EFFECTOR STUDIES
CONDITIONAL MUTATOR GENE IN ESCHERICHIA-COLI - ISOLATION, MAPPING, AND EFFECTOR STUDIES
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DOI：
10.1128/jb.117.2.477-487.1974
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发表时间：
1974-01-01
影响因子：
3.2
通讯作者：
COX, EC
中科院分区：
文献类型：
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作者：
DEGNEN, GE;COX, EC
在大肠杆菌中发现了一个条件突变基因mutD 5。通过P1转导，已显示其位于染色体上约5.7 min处，与proA和argF共转导。在丰富的培养基中，链霉素和萘啶酸抗性突变频率比在基本培养基中高50至100倍。在基本培养基中，mut D5诱导的突变频率仍然比共同基因野生型（mut+）水平高50至100倍。用所有测试的标记物获得类似的结果。培养基中低至0.04 μM浓度的胸苷或由胸腺嘧啶加脱氧核糖基供体内源性生成的胸苷可提高突变频率。脱氧腺苷、各种核糖核苷、胸腺嘧啶和2-脱氧核糖不刺激突变。这些效应都与生长速率无关，因为生长速率和突变速率可以完全解耦。
A mutator gene,mutD5, whose phenotype is conditional, has been identified inEscherichia coli. By P1 transduction it has been shown to lie at about 5.7 min on the chromosome, being co-transduced withproAandargF. In rich medium, streptomycin- and nalidixic acid-resistant mutation frequencies are 50 to 100 times higher than those in minimal medium. In minimal medium, themutD5-induced mutation frequencies are still 50 to 100 times above co-isogenic wild-type (mut+) levels. Similar results were obtained with all markers tested. Mutant frequencies can be raised by thymidine in the medium at concentrations as low as 0.04 μM, or by the endogenous generation of thymidine from thymine plus a deoxyribosyl donor. Deoxyadenosine, various ribonucleosides, thymine, and 2-deoxyribose do not stimulate mutation. None of these effects are related to growth rate, since growth rate and mutation rate can be decoupled completely.