Tracking F plasmid TraI relaxase processing reactions provides insight into F plasmid transfer.
Tracking F plasmid TraI relaxase processing reactions provides insight into F plasmid transfer.
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DOI：
10.1093/nar/gkq1137
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发表时间：
2011-04
影响因子：
14.9
通讯作者：
Schildbach JF
中科院分区：
文献类型：
--
作者：
Dostál L;Shao S;Schildbach JF
在F质粒接合转移的早期，F松弛酶TraI在转移起点内称为nic的位点切割一条质粒链。该反应将TraI Tyr 16共价连接到5′-ssDNA磷酸。最后，TraI逆转切割反应，使质粒链环化。连接反应需要ssDNA 3′-羟基;在nic处的第二次切割反应，通过从质粒切割位点延伸再生，可以产生这个羟基。在此，我们确认TraI在转移过程中被运送到接收方。我们跟踪了二次切割反应，并提供了证据，它发生在供体和F ssDNA转移到受体与游离的3′-羟基。Phe取代TraI活性位点内的四个Tyr仅涉及转移所需的两个裂解反应中的Tyr 16。因此，F质粒转移需要两个TraI分子。对各种线性和环状ssDNA底物上TraI易位的分析支持了TraI从切割的F质粒的3 '末端缓慢解离的断言，这可能是质粒再环化所必需的特征。
Early in F plasmid conjugative transfer, the F relaxase, TraI, cleaves one plasmid strand at a site within the origin of transfer called nic. The reaction covalently links TraI Tyr16 to the 5′-ssDNA phosphate. Ultimately, TraI reverses the cleavage reaction to circularize the plasmid strand. The joining reaction requires a ssDNA 3′-hydroxyl; a second cleavage reaction at nic, regenerated by extension from the plasmid cleavage site, may generate this hydroxyl. Here we confirm that TraI is transported to the recipient during transfer. We track the secondary cleavage reaction and provide evidence it occurs in the donor and F ssDNA is transferred to the recipient with a free 3′-hydroxyl. Phe substitutions for four Tyr within the TraI active site implicate only Tyr16 in the two cleavage reactions required for transfer. Therefore, two TraI molecules are required for F plasmid transfer. Analysis of TraI translocation on various linear and circular ssDNA substrates supports the assertion that TraI slowly dissociates from the 3′-end of cleaved F plasmid, likely a characteristic essential for plasmid re-circularization.
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DOI：
10.1111/j.1432-1033.1994.tb20065.x
发表时间：
1994-12-01
期刊：
EUROPEAN JOURNAL OF BIOCHEMISTRY
影响因子：
--
作者：
GRANDOSO, G;LLOSA, M;DELACRUZ, F
通讯作者：
DELACRUZ, F
影响因子：
3.6
作者：
DASH, PK;TRAXLER, BA;MINKLEY, EG
通讯作者：
MINKLEY, EG
影响因子：
3.2
作者：
Dostal, Lubomir;Schildbach, Joel F.
通讯作者：
Schildbach, Joel F.
DOI：
10.1073/pnas.0506081102
发表时间：
2005-11-08
影响因子：
11.1
作者：
Draper, O;César, CE;Llosa, M
通讯作者：
Llosa, M
影响因子：
14.9
作者：
Hekman K;Guja K;Larkin C;Schildbach JF
通讯作者：
Schildbach JF