Berg O G, Silva P J
Department of Molecular Biology, University of Uppsala Biomedical Center, Box 590, S-75124, Uppsala, Sweden.
Nucleic Acids Res. 1997 Apr 1;25(7):1397-404. doi: 10.1093/nar/25.7.1397.
The codon bias in Escherichia coli for all two-fold degenerate amino acids was studied as dependent on the context from the six bases in the nearest surrounding codons. By comparing the results in genes at different expression levels, effects that are due to differences in mutation rates can be distinguished from those that are due to selection. Selective effects on the codon bias is found mostly from the first neighbouring base in the 3'direction, while neighbouring bases further away influence mostly the mutational bias. In some cases it is also possible to identify specific molecular processes, repair or avoidance of frame shift, that lead to the context dependence of the bias.
研究了大肠杆菌中所有双重简并氨基酸的密码子偏好性，该偏好性取决于最近邻密码子中六个碱基的上下文。通过比较不同表达水平基因的结果，可以将由突变率差异引起的效应与由选择引起的效应区分开来。对密码子偏好性的选择效应主要来自3'方向的第一个相邻碱基，而更远的相邻碱基主要影响突变偏好性。在某些情况下，还可以识别导致偏好性上下文依赖性的特定分子过程，如移码修复或避免。
