The outer membrane secretin PilQ from Neisseria meningitidis binds DNA.
The outer membrane secretin PilQ from Neisseria meningitidis binds DNA.
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DOI：
10.1099/mic.0.2006/004200-0
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发表时间：
2007-05
期刊：
影响因子：
--
通讯作者：
Tønjum T
中科院分区：
文献类型：
--
作者：
Assalkhou R;Balasingham S;Collins RF;Frye SA;Davidsen T;Benam AV;Bjørås M;Derrick JP;Tønjum T
脑膜炎奈瑟菌在其整个生长周期中具有天然的转化能力。毛系物种的转化与IV型毛的表达相耦合，IV型毛以束状丝状附属物的形式存在于细胞表面，由毛生成分组装、挤压和收缩。在转化过程的初始阶段，DNA的结合和摄取通过假定的外膜通道进入外周质。这项研究表明，DNA仅与纯化的菌毛结合较弱，但与直接从脑膜炎球菌膜分离的PilQ复合物结合显著。通过对天然复合物PilQ以及重组截短的PilQ单体的DNA结合活性的评估，结果表明，PilQ的n端区域参与了与DNA的相互作用。可见，ssDNA与PilQ的结合比dsDNA的结合具有更高的亲和力。然而，DNA与PilQ的结合并不依赖于neisserial DNA摄取序列的存在。这表明，转化DNA是通过由PilQ复合物形成的外膜通道引入细胞的，DNA摄取是通过非特异性的DNA引入加上菌毛缩回，然后呈递给包括PilQ在内的DNA结合组分而发生的。
Neisseria meningitidis is naturally competent for transformation throughout its growth cycle. Transformation in neisserial species is coupled to the expression of type IV pili, which are present on the cell surface as bundled filamentous appendages, and are assembled, extruded and retracted by the pilus biogenesis components. During the initial phase of the transformation process, binding and uptake of DNA takes place with entry through a presumed outer-membrane channel into the periplasm. This study showed that DNA associates only weakly with purified pili, but binds significantly to the PilQ complex isolated directly from meningococcal membranes. By assessing the DNA-binding activity of the native complex PilQ, as well as recombinant truncated PilQ monomers, it was shown that the N-terminal region of PilQ is involved in the interaction with DNA. It was evident that the binding of ssDNA to PilQ had a higher affinity than the binding of dsDNA. The binding of DNA to PilQ did not, however, depend on the presence of the neisserial DNA-uptake sequence. It is suggested that transforming DNA is introduced into the cell through the outer-membrane channel formed by the PilQ complex, and that DNA uptake occurs by non-specific introduction of DNA coupled to pilus retraction, followed by presentation to DNA-binding component(s), including PilQ.
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影响因子：
3.2
作者：
Collins, RF;Ford, RC;Derrick, JP
通讯作者：
Derrick, JP
影响因子：
4.8
作者：
Collins, RF;Frye, SA;Derrick, JP
通讯作者：
Derrick, JP
影响因子：
3.2
作者：
Graupner, S;Weger, N;Wackernagel, W
通讯作者：
Wackernagel, W
影响因子：
3.6
作者：
Bitter, W;Koster, M;Tommassen, J
通讯作者：
Tommassen, J
淋病奈瑟菌特异性转化中识别的 DNA 序列的鉴定和排列
DOI：
10.1073/pnas.85.18.6982
发表时间：
1988-09-01
影响因子：
11.1
作者：
GOODMAN, SD;SCOCCA, JJ
通讯作者：
SCOCCA, JJ