Replacement of the lysine residue in the consensus ATP-binding sequence of the AddA subunit of AddAB drastically affects chromosomal recombination in transformation and transduction of Bacillus subtilis
Replacement of the lysine residue in the consensus ATP-binding sequence of the AddA subunit of AddAB drastically affects chromosomal recombination in transformation and transduction of Bacillus subtilis
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DOI：
10.1046/j.1365-2958.1996.601424.x
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发表时间：
1996-09-01
影响因子：
3.6
通讯作者：
Meima, R
中科院分区：
文献类型：
--
作者：
Haijema, BJ;Noback, M;Meima, R
枯草芽孢杆菌依赖于ATP的脱氧核糖核酸酶复合体(AddAB)具有两个共同的ATP结合序列，位于这两个亚基的N端区域。用甘氨酸取代了两个常见的ATP结合序列中高度保守的赖氨酸残基，得到了突变的酶复合体AddAB-A-K36G(AddA*B)和AddAB-B-K14G(AddAB*)。AddA亚基突变减少了DNA修复和染色体转化，并取消了噬菌体PBS1介导的转导。该突变还导致依赖于ATP的核酸外切酶和解旋酶活性完全丧失。相比之下，AddB亚单位的突变只有轻微的影响。Recf和addAB基因与质粒DNA的转化不是必需的，但在与染色体DNA的转化中具有重叠的活性。与RECF不同，AddAB酶在PBS1介导的信号转导中起着至关重要的作用。然而，与addAB相比，recf在DNA修复方面具有更重要的作用。
The ATP-dependent deoxyribonuclease enzyme complex (AddAB) of Bacillus subtilis possesses two consensus ATP-binding sequences, located in the N-terminal region of both subunits. The highly conserved lysine residues in both consensus ATP-binding sequences were replaced by glycine, resulting in the mutant enzyme complexes AddAB-A-K36G (AddA*B) and AddAB-B-K14G (AddAB*). The mutation in subunit AddA reduced DNA repair and chromosomal transformation, and abolished bacteriophage PBS1-mediated transduction. This mutation also resulted in a complete loss of the ATP-dependent exonuclease and helicase activity. In contrast, the mutation in subunit AddB had only marginal effects. The recF and addAB genes are not required for transformation with plasmid DNA, but have overlapping activities in transformation with chromosomal DNA. By contrast to RecF, the AddAB enzyme is essential for PBS1-mediated transduction. However, recF has a more important function with respect to DNA repair than addAB.