Muller R E, Ano T, Imanaka T, Aiba S
Mol Gen Genet. 1986 Jan;202(1):169-71. doi: 10.1007/BF00330534.
The deletion plasmids, pRBH1 (1.5 MDa, kanamycin resistance, Kmr) and pUB110dB (1.5 MDa, Kmr), were obtained from pTB913 (2.9 MDa, Kmr, isolated from a thermophilic bacillus) and pUB110 (3.0 MDa, Kmr, from Staphylococcus aureus), respectively. All the nucleotide sequences of these deletion plasmids were determined. Replication origin regions of pRBH1 and pUB110dB contained, respectively, 63 base-pair inverted repeat and a large open reading frame, encoding RepB protein (235 amino acid residues). The nucleotide sequences were identical to each other except for one base in the center of the inverted repeat. Two copy number mutant plasmids, pRBHC3 and pRBHC7, were obtained from pRBH1. The mutation points were located at different positions in the RepB protein coding region (Gly to Asp for pRBHC3 and Gly to Glu for pRBHC7). RepB protein was shown to be involved in the copy number control of these plasmids.
缺失质粒pRBH1（1.5兆道尔顿，卡那霉素抗性，Kmr）和pUB110dB（1.5兆道尔顿，Kmr）分别从pTB913（2.9兆道尔顿，Kmr，从嗜热芽孢杆菌中分离得到）和pUB110（3.0兆道尔顿，Kmr，来自金黄色葡萄球菌）获得。测定了这些缺失质粒的所有核苷酸序列。pRBH1和pUB110dB的复制起始区域分别包含63个碱基对的反向重复序列和一个大的开放阅读框，编码RepB蛋白（235个氨基酸残基）。除了反向重复序列中心的一个碱基外，核苷酸序列彼此相同。从pRBH1获得了两个拷贝数突变体质粒pRBHC3和pRBHC7。突变点位于RepB蛋白编码区的不同位置（pRBHC3为甘氨酸突变为天冬氨酸，pRBHC7为甘氨酸突变为谷氨酸）。已表明RepB蛋白参与这些质粒的拷贝数控制。
