RELEASE OF ESCHERICHIA-COLI DNA FROM MEMBRANE COMPLEXES BY SINGLE-STRAND ENDONUCLEASES
RELEASE OF ESCHERICHIA-COLI DNA FROM MEMBRANE COMPLEXES BY SINGLE-STRAND ENDONUCLEASES
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DOI：
10.1073/pnas.74.7.2756
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发表时间：
1977-01-01
影响因子：
11.1
通讯作者：
SCHAECHTER, M
中科院分区：
文献类型：
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作者：
ABE, M;BROWN, C;SCHAECHTER, M
温和制备的E.用单链特异性核酸内切酶（S1 [来自曲霉属]或来自绿豆）与大肠杆菌的杂交导致约90%的DNA从膜上释放，如M [膜相关DNA]带技术所测定的。释放的DNA的平均分子量约为1.2 × 104。108.用核酸内切酶S1获得的数据符合数学模型，其中底物位点在膜附着位点处或附近。用胰腺或X射线获得的数据符合DNA沿着随机位点双链断裂的模型。将数据拟合到这些模型中，有18 .+-。5个膜附着位点。S1核酸酶处理后剩余的DNA富集在染色体复制起点附近的区域。因此，在该区域的附着似乎与DNA沿着的其他位点的附着在化学上不同。
Treatment of gently prepared lysates of E. coli with single-strand-specific endonuclease (S1 [from Aspergillus oryzae] or from mung beans) results in the release of about 90% of the DNA from membranes, as determined by the M [membrane associated DNA] band technique. The released DNA has an average MW of about 1.2 .times. 108. Data obtained with endonuclease S1 fit a mathematical model in which substrate sites are at or near membrane attachment sites. Data obtained with pancreatic or X-rays fit a model for double-strand breaks at random sites along the DNA. Fitting data to these models, there are 18 .+-. 5 membrane attachment sites. The DNA remaining after S1 nuclease treatment is enriched for the region near the origin of chromosome replication. Therefore attachment at this region appears to be chemically different from that at the other sites along the DNA.