TRANSIENT GENERATION OF DISPLACED SINGLE-STRANDED-DNA DURING NICK TRANSLATION
TRANSIENT GENERATION OF DISPLACED SINGLE-STRANDED-DNA DURING NICK TRANSLATION
复制标题
DOI：
10.1016/0092-8674(82)90404-4
复制
发表时间：
1982-01-01
期刊：
影响因子：
64.5
通讯作者：
OLIVERA, BM
中科院分区：
文献类型：
--
作者：
LUNDQUIST, RC;OLIVERA, BM
移位的单链突出端在大肠杆菌DNA聚合酶I的切口平移期间瞬时产生和破坏。讨论了超重组突变体具有此类突出端结构频率增加的证据。突出端的瞬时产生对于一般重组可能是重要的。5“fwdarw.聚合酶I的3“外切核酸酶活性特异性地水解这样的突出端以产生切口。突出端通过聚合产生，但在每个聚合步骤之后，聚合酶或核酸外切酶可以起作用-55%的时间，聚合首先发生。在该频率下，每聚合1300个核苷酸产生12个核苷酸。许多DNA链的不连续性是单链的突出端，而不是缺口或简单的缺口。
Displaced single-stranded overhangs are transiently generated and destroyed during nick translation by Escherichia coli DNA polymerase I. Evidence that hyper-rec mutants have an increased frequency of such overhang structures is discussed. The transient generation of overhangs may be significant for general recombination. The 5'' .fwdarw. 3'' exonuclease activity of polymerase I specifically hydrolyzes such overhangs to yield a nick. Overhangs are generated by polymerization, but after every polymerization step, either polymerase or exonuclease can act-55% of the time, polymerization occurred first. At this frequency overhangs of .gtoreq. 12 nucleotides are generated every 1300 nucleotides polymerized. Many DNA strand discontinuities are displaced single-strand overhangs, rather than gaps or simple nicks.