Sequence of plasmid pGT5 from the archaeon Pyrococcus abyssi: Evidence for rolling-circle replication in a hyperthermophile
Sequence of plasmid pGT5 from the archaeon Pyrococcus abyssi: Evidence for rolling-circle replication in a hyperthermophile
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DOI：
10.1128/jb.178.11.3232-3237.1996
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发表时间：
1996-06-01
影响因子：
3.2
通讯作者：
Forterre, P
中科院分区：
文献类型：
--
作者：
Erauso, G;Marsin, S;Forterre, P
已对来自超嗜热古菌Pyrococcus abyssi GE 5的质粒pGT 5（3，444 bp）进行了完全测序。具有良好编码概率的两个主要开放阅读框位于同一条链上，并覆盖总序列的85%。较大的开放阅读框编码一个推定的多肽，该多肽与使用滚环机制复制的质粒的Rep蛋白具有序列相似性。在这个开放阅读框架的上游，我们检测到一个11 bp的基序，与通过滚环机制复制的几种细菌质粒的双链起源相同。一个假定的单链起源表现出相似性，细菌引发体依赖的单链起始位点和细菌引发酶（dnaG）的起始位点。在深海毕赤酵母细胞中检测到对应于正链的单链形式的pGT 5。这些数据表明，pGT5复制通过滚环机制，并建议，成员的结构域pGT5包含几个细菌蛋白质的同源物参与染色体DNA复制。从滚环复制子的Rep蛋白的系统发育分析表明，不同的家庭分歧之前分离的域的细菌，真核生物。
The plasmid pGT5 (3,444 bp) from the hyperthermophilic archaeon Pyrococcus abyssi GE5 has been completely sequenced. Two major open reading frames with a good coding probability are located on the same strand and cover 85% of the total sequence. The larger open reading frame encodes a putative polypeptide which exhibits sequence similarity with Rep proteins of plasmids using the rolling-circle mechanism for replication. Upstream of this open reading frame, we have detected an 11-bp motif identical to the double-stranded origin of several bacterial plasmids that replicate via the rolling circle mechanism. A putative single-stranded origin exhibits similarities both to bacterial primosome-dependent single-stranded initiation sites and to bacterial primase (dnaG) start sites. A single-stranded form of pGT5 corresponding to the plus strand was detected in cells of P. abyssi. These data indicate that pGT5 replicates via the rolling-circle mechanism and suggest that members of the domain Archaea contain homologs of several bacterial proteins involved in chromosomal DNA replication. Phylogenetic analysis of Rep proteins from rolling-circle replicons suggest that diverse families diverged before the separation of the domains Archaea, Bacteria, and Eucarya.