McBeth D L, Shapiro J A
Mol Gen Genet. 1984;197(3):384-91. doi: 10.1007/BF00329933.
We analyzed the reversion of strains carrying alk208, a mutation in the alkBAC (alkane utilization) region of the Pseudomonas CAM-OCT plasmid. Reversion of alk208 was stimulated 25 to 75-fold by small doses of UV-irradiation. All alkane hydroxylase-positive (AlkB+) revertants proved to be aliphatic alcohol dehydrogenase-positive (AlkC+) as well, whereas AlkC+ revertants could be either AlkB+ or AlkB-. Most of the AlkB- AlkC+ partial revertants produced AlkC- segregants at measurable frequencies. UV-irradiation substantially increased the rate of AlkC- segregation. Most segregants reverted to AlkB+ or AlkC+ at frequencies similar to the original alk208 strain. Dot blot hybridization analyses using cloned probes from various regions of CAM-OCT revealed that the partial revertants contained specific amplications of alk DNA. The endpoints of these amplifications mapped in at least two regions. AlkC- segregants had lost the DNA amplifications.
我们分析了携带alk208的菌株的回复突变情况，alk208是假单胞菌CAM - OCT质粒的alkBAC（烷烃利用）区域中的一个突变。小剂量紫外线照射可使alk208的回复突变频率提高25至75倍。所有烷烃羟化酶阳性（AlkB +）的回复突变体经证实也是脂肪族醇脱氢酶阳性（AlkC +），而AlkC +回复突变体可以是AlkB +或AlkB -。大多数AlkB - AlkC +部分回复突变体以可测量的频率产生AlkC - 分离子。紫外线照射显著提高了AlkC - 分离子的产生速率。大多数分离子回复为AlkB +或AlkC +的频率与原始alk208菌株相似。使用来自CAM - OCT不同区域的克隆探针进行的斑点印迹杂交分析表明，部分回复突变体含有alk DNA的特异性扩增。这些扩增的终点至少定位于两个区域。AlkC - 分离子已失去DNA扩增。
