Differential effects of myeloperoxidase-derived oxidants on Escherichia coli DNA replication.
Differential effects of myeloperoxidase-derived oxidants on Escherichia coli DNA replication.
复制标题
髓过氧化物酶衍生的氧化剂对大肠杆菌 DNA 复制的不同影响。
DOI：
10.1128/iai.66.6.2655-2659.1998
复制
发表时间：
1998
影响因子：
3.1
通讯作者：
Hughes,JP
中科院分区：
文献类型：
--
作者：
Rosen,H;Michel,BR;vanDevanter,DR;Hughes,JP
髓过氧化物酶（MPO）-H_2O_2-氯化物体系对大肠杆菌DNA的合成有很强的抑制作用。此外，MPO处理的E的细胞被膜。大肠杆菌细胞失去了它们与foriC（染色体复制起点）的半甲基化DNA序列相互作用的能力，提出了DNA合成抑制涉及foriC相关功能损害的前景（H.罗森等人，美国国家科学院院刊，Acad. Sci. USA，87：10048-10052，1990）。目的：探讨髓过氧化物酶（MPO）对E.大肠杆菌DNA合成，质粒DNA复制进行了比较，总（染色体）DNA复制的六个质粒与三个不同的复制起点。质粒pCM 700复制，复制从oriC，是敏感的MPO介导的抑制总（染色体）DNA复制。描述这种关系的回归线的斜率为0.90，而th 2为0.89。相反，四种非oriC质粒中的三种，pUC 19、pACYC 184和pSC 101的复制活性显示出对MPO衍生的氧化剂抑制的显著早期抗性。这种抗性模式的例外是质粒pSP 102，其来源于P1噬菌体。pSP 102复制下降类似于总DNA合成。pSP 102复制与总DNA合成的回归线的斜率为0.95，ther 2为0.92。P1介导的复制的生化要求与oriC介导的复制的生化要求惊人地相似。有人提出，这些要求之一，共同tooriC和P1的起源，但不是关键的复制的其他non-oriC质粒，是一个重要的目标MPO介导的氧化介导的初始下降inE。大肠杆菌染色体DNA合成。
The microbicidal myeloperoxidase (MPO)-H2O2-chloride system strongly inhibitsEscherichia coliDNA synthesis. Also, cell envelopes from MPO-treatedE. colicells lose their ability to interact with hemimethylated DNA sequences oforiC, the chromosomal origin of replication, raising the prospect that suppression of DNA synthesis involves impairment oforiC-related functions (H. Rosen, et al. Proc. Natl. Acad. Sci. USA, 87:10048–10052, 1990). To evaluate whether origin-specific DNA sequences play a role in the MPO effect onE. coliDNA synthesis, plasmid DNA replication was compared to total (chromosomal) DNA replication for six plasmids with three distinct origins of replication. Plasmid pCM700 replication, replicating fromoriC, was as sensitive to MPO-mediated inhibition as was total (chromosomal) DNA replication. A regression line describing this relationship had a slope of 0.90, and ther2was 0.89. In contrast, the replication activities of three of four non-oriCplasmids, pUC19, pACYC184, and pSC101, demonstrated significant early resistance to inhibition by MPO-derived oxidants. The exception to this resistance pattern was plasmid pSP102, which has an origin derived from P1 phage. pSP102 replication declined similarly to that of total DNA synthesis. The regression line for pSP102 replication versus total DNA synthesis had a slope of 0.95, and ther2was 0.92. The biochemical requirements for P1-mediated replication are strikingly similar to those fororiC-mediated replication. It is proposed that one of these requirements, common tooriCand the P1 origin but not critical to the replication of the other non-oriCplasmids, is an important target for MPO-mediated oxidations that mediate the initial decline inE. colichromosomal DNA synthesis.