Soj (ParA) DNA binding is mediated by conserved arginines and is essential for plasmid segregation
Soj (ParA) DNA binding is mediated by conserved arginines and is essential for plasmid segregation
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DOI：
10.1073/pnas.0705196105
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发表时间：
2007-12-18
影响因子：
11.1
通讯作者：
Lutkenhaus, Joe
中科院分区：
文献类型：
--
作者：
Hester, Christina M.;Lutkenhaus, Joe
Soj是参与质粒和染色体分离的ATP酶的帕拉家族的成员。它结合非特异性和合作的DNA，虽然这种结合的功能是未知的。在这里，我们表明，保守的精氨酸残基，映射到枯草芽孢杆菌Soj的表面的突变引起的核苷酸依赖性二聚化只有最小的影响，但对DNA结合有显着的影响。使用模型质粒分配系统在大肠杆菌中，我们发现Soj DNA结合突变体是缺乏质粒分离。Soj结构上的三聚体的位置解释了DNA结合依赖于二聚化的原因，并被用来定向DNA上的Soj二聚体，揭示了Soj聚合的轴。精氨酸残基在其他染色体同源物中是保守的，包括新月柄杆菌、铜绿假单胞菌、恶臭假单胞菌、天蓝色链霉菌和霍乱弧菌的染色体I的ParA，这表明DNA结合是该家族成员的共同特征。
Soj is a member of the ParA family of ATPases involved in plasmid and chromosomal segregation. It binds nonspecifically and cooperatively to DNA although the function of this binding is unknown. Here, we show that mutation of conserved arginine residues that map to the surface of Bacillus subtilis Soj caused only minimal effects on nucleotide-dependent dimerization but had dramatic effects on DNA binding. Using a model plasmid partitioning system in Escherichia coli, we find that Soj DNA-binding mutants are deficient in plasmid segregation. The location of the arginines on the Soj structure explains why DNA binding depends on dimerization and was used to orient the Soj dimer on the DNA, revealing the axis of Soj polymerization. The arginine residues are conserved among other chromosomal homologues, including the ParAs from Caulobacter crescentus, Pseudomonas aeruginosa, Pseudomonas putida, Streptomyces coelicolor, and chromosome I of Vibrio cholerae indicating that DNA binding is a common feature of members of this family.