Cox G B, Webb D, Hatch L, Lightowlers R, Munn A, Gibson F
J Bacteriol. 1987 Jul;169(7):2945-9. doi: 10.1128/jb.169.7.2945-2949.1987.
The nucleotide sequence of the previously described uncC424 allele was determined and found to be the same as that of a wild-type uncC gene. However, a G----A change occurred 7 nucleotides upstream from the translation start codon, changing the putative Shine-Dalgarno sequence from GAGG to GAAG. Four revertant strains were examined. In one revertant, which had normal growth and membrane properties, a single base deletion had occurred to re-form the Shine-Dalgarno sequence GAGG 1 nucleotide closer to the translation start codon. A second revertant had a single base deletion in the preceding uncD gene, causing an extension of the beta subunit by 6 amino acids and an increase, presumably by translational coupling, in the amount of epsilon subunit. The third and fourth revertant strains were phenotypically similar and had either C----T or G----T changes 18 or 19 nucleotides, respectively, upstream from the translation start codon.
已确定先前描述的uncC424等位基因的核苷酸序列，发现其与野生型uncC基因的序列相同。然而，在翻译起始密码子上游7个核苷酸处发生了G→A的变化，使假定的Shine-Dalgarno序列从GAGG变为GAAG。对4个回复突变株进行了检测。在一个生长和膜特性正常的回复突变株中，发生了一个单碱基缺失，使Shine-Dalgarno序列重新形成GAGG，且距翻译起始密码子近了1个核苷酸。第二个回复突变株在其上游的uncD基因中有一个单碱基缺失，导致β亚基延长了6个氨基酸，并且推测由于翻译偶联，ε亚基的量增加。第三和第四个回复突变株在表型上相似，在翻译起始密码子上游分别有18或19个核苷酸的C→T或G→T变化。
