Franden M A, McHenry C S
Department of Biochemistry and Genetics, University of Colorado Health Sciences Center, Denver 80262.
Nucleic Acids Res. 1988 Jul 25;16(14A):6353-60. doi: 10.1093/nar/16.14.6353.
Monoclonal antibodies directed against the alpha subunit of the DNA polymerase III holoenzyme (1) of E. coli were tested for cross-reactivity with a variety of polymerases. We found that one monoclonal antibody bound to E. coli DNA polymerase I as well as to DNA polymerase III. A weaker, but specific, interaction was also detected with T4 DNA polymerase. We exploited the proteolysis procedure developed by Setlow, Brutlag and Kornberg (2) to determine which domain of DNA polymerase I contained the conserved epitope. Contrary to expectations, it was not found in the polymerase domain, but in the 5'----3' exonuclease domain. This reveals a sequence or structure, sufficiently important to be conserved among these polymerases, that is not directly involved in the polymerization reaction.
针对大肠杆菌DNA聚合酶III全酶α亚基（1）的单克隆抗体，被检测与多种聚合酶的交叉反应性。我们发现一种单克隆抗体既能与大肠杆菌DNA聚合酶I结合，也能与DNA聚合酶III结合。与T4 DNA聚合酶也检测到较弱但特异的相互作用。我们利用Setlow、Brutlag和Kornberg（2）开发的蛋白酶解方法，来确定DNA聚合酶I的哪个结构域含有保守表位。与预期相反，它不在聚合酶结构域中，而是在5'→3'核酸外切酶结构域中。这揭示了一个在这些聚合酶中足够重要而得以保守的序列或结构，它并不直接参与聚合反应。
