Methylated cytosine at Dcm (CCTAGG) sites in Escherichia coli: Possible function and evolutionary implications
Methylated cytosine at Dcm (CCTAGG) sites in Escherichia coli: Possible function and evolutionary implications
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大肠杆菌中 Dcm (CCTAGG) 位点的甲基化胞嘧啶：可能的功能和进化意义
DOI：
10.1007/bf00170457
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发表时间：
1993
影响因子：
3.9
通讯作者：
J. Ramírez
中科院分区：
文献类型：
--
作者：
M. Gómez;J. Ramírez
研究了49株大肠杆菌（E. coliDNA位点（207，530 bp）。结果表明：（1）Dcm位点的频率高于随机分布的预期值，但低于Markov链分析的计算值;（2）CCTGG位点在编码区的频率高于非编码区，而CCAGG位点的频率则相反;（4）oriC上的Dcm位点对DNA复制的准确启动可能并不重要;（5）密码子中的5-MeC在第一位的频率高于第二位和第三位;（6）可能很少有基因的突变率主要由DNA甲基化决定。有人提出，Dcm甲基化酶的功能是保护染色体DNA从限制性内切酶EcoRII。Dcm甲基化对确定寡核苷酸频率、突变率和重组水平的贡献，从而确定E.大肠杆菌基因组，可以解释为这种甲基化的收购的结果。
The frequency and distribution of methylated cytosine (5-MeC) at CCTAGG (Dcm sites) in 49 E. coli DNA loci (207,530 bp) were determined. Principal observations of this analysis were: (1) Dcm frequency was higher than expected from random occurrence but lower than calculated with Markov chain analysis; (2) CCTGG sites were found more frequently in coding than in noncoding regions, while the opposite was true for CCAGG sites; (3) Dcm site distribution does not exhibit any identifiably regular pattern on the chromosome; (4) Dcm sites at oriC are probably not important for accurate initiation of DNA replication; (5) 5-MeC in codons was more frequently found in first than in second and third positions; (6) there are probably few genes in which the mutation rate is determined mainly by DNA methylation. It is proposed that the function of Dcm methylase is to protect chromosomal DNA from restriction-enzyme EcoRII. The Dcm methylation contribution to determine frequency of oligonucleotides, mutation rate, and recombination level, and thus evolution of the E. coli genome, could be interpreted as a consequence of the acquisition of this methylation.
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影响因子：
14.9
作者：
BHAGWAT, AS;MCCLELLAND, M
通讯作者：
MCCLELLAND, M
影响因子：
14.9
作者：
PHILLIPS, GJ;ARNOLD, J;IVARIE, R
通讯作者：
IVARIE, R
dam 甲基化对 Tn5 转座的影响。
影响因子：
5.6
作者：
Yin,JC;Krebs,MP;Reznikoff,WS
通讯作者：
Reznikoff,WS
大肠杆菌中的 DNA 甲基化。
影响因子：
11.1
作者：
Marinus,MG
通讯作者：
Marinus,MG