• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Molecular and Cellular Biology >Fidelity of DNA polymerase I and the DNA polymerase I-DNA primase complex from Saccharomyces cerevisiae.
【24h】

Fidelity of DNA polymerase I and the DNA polymerase I-DNA primase complex from Saccharomyces cerevisiae.

机译：来自酿酒酵母的DNA聚合酶I和DNA聚合酶I-DNA引发酶复合物的保真度。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We have determined the fidelity of DNA synthesis by DNA polymerase I (yPol I) from Saccharomyces cerevisiae. To determine whether subunits other than the polymerase catalytic subunit influence fidelity, we measured the accuracy of yPol I purified by conventional procedures, which yields DNA polymerase with a partially proteolyzed catalytic subunit and no associated primase activity, and that of yPol I purified by immunoaffinity chromatography, which yields polymerase having a single high-molecular-weight species of the catalytic subunit, as well as three additional polypeptides and DNA primase activity. In assays that score polymerase errors within the lacZ alpha-complementation gene in M13mp2 DNA, yPol I and the yPol I-primase complex produced single-base substitutions, single-base frameshifts, and larger deletions. For specific errors and template positions, the two forms of polymerase exhibited differences in fidelity that could be as large as 10-fold. Nevertheless, results for the overall error frequency and the spectrum of errors suggest that the yPol I-DNA primase complex is not highly accurate and that, just as for the polymerase alone, its fidelity is not sufficient to account for a low spontaneous mutation rate in vivo. The specificity data also suggest models to explain -1 base frameshifts in nonrepeated sequences and certain complex deletions by a direct repeat mechanism involving aberrant loop-back synthesis.
机译：我们已经确定了来自酿酒酵母的DNA聚合酶I（yPol I）进行DNA合成的保真度。为了确定除聚合酶催化亚基以外的其他亚基是否影响保真度，我们测量了通过常规程序纯化的yPol I的准确性，该方法可产生具有部分蛋白水解的催化亚基且无相关的启动酶活性的DNA聚合酶，以及通过免疫亲和层析纯化的yPol I产生具有单个高分子量种类的催化亚基的聚合酶，以及三个附加的多肽和DNA primase活性。在对M13mp2 DNA的lacZ alpha互补基因内的聚合酶错误进行评分的测定中，yPol I和yPol I-引物酶复合物产生单碱基取代，单碱基移码和较大的缺失。对于特定的错误和模板位置，两种形式的聚合酶在保真度方面表现出的差异可能高达10倍。然而，总错误频率和错误谱的结果表明，yPol I-DNA primase复合物不是很准确，而且，就象单独的聚合酶一样，其保真度不足以说明低自发突变率。体内。特异性数据还提出了模型，可通过涉及异常环回合成的直接重复机制来解释非重复序列中的-1个碱基移码和某些复杂的缺失。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号