Genetic analysis of a novel plasmid pZMX101 from Halorubrum saccharovorum: determination of the minimal replicon and comparison with the related haloarchaeal plasmid pSCM201.
Genetic analysis of a novel plasmid pZMX101 from Halorubrum saccharovorum: determination of the minimal replicon and comparison with the related haloarchaeal plasmid pSCM201.
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DOI：
10.1111/j.1574-6968.2007.00656.x
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发表时间：
2007-05
影响因子：
2.1
通讯作者：
Ligang Zhou;Meixian Zhou;Chaomin Sun;H. Xiang;H. Tan
中科院分区：
文献类型：
--
作者：
Ligang Zhou;Meixian Zhou;Chaomin Sun;H. Xiang;H. Tan
测定了一个新的嗜盐古菌质粒pZMX 101（3918 bp）的DNA序列，并预测了6个开放阅读框。最大的ORF编码一个假定的复制起始蛋白RepA，其与最近从盐节藻分离的θ-复制质粒pSCM 201的Rep 201具有40%的序列相似性，表明pZMX 101可能通过θ-型机制复制。以pZMX 101为唯一的盐古菌复制子，构建了穿梭载体pZMX 108，并成功转化了火山盐铁菌（Haloferax volcanii）DS 70。在此基础上，确定了pZMX 101的最小复制子（1978 bp）。它由repA基因和c.上游400-bp和下游300-bp序列。值得注意的是，pZMX 101和pSCM 201的假定复制起点包含不同类型的序列基序，并且这两个质粒分别对Haloferax和Haloarcula表现出不同的宿主偏好性。
The DNA sequence of a novel haloarchaeal plasmid pZMX101 (3918 bp) from Halorubrum saccharovorum was determined and six ORFs were predicted. The largest ORF encodes a putative replication initiation protein RepA, which shares 40% sequence similarity with the Rep201 of a theta-replication plasmid pSCM201 recently isolated from Haloarcula, suggesting that pZMX101 might replicate via a theta-type mechanism. Using pZMX101 as the only haloarchaeal replicon, a shuttle vector pZMX108 was constructed and successfully transformed into Haloferax volcanii DS70. Based on this in vivo system, the minimal replicon (1978 bp) of pZMX101 was determined. It is composed of the repA gene plus c. 400-bp upstream and 300-bp downstream sequences. Significantly, the putative replication origin of pZMX101 and that of pSCM201 contain different types of sequence motifs, and these two plasmids exhibit distinct host preference for Haloferax and Haloarcula, respectively.