Vol 47(2013) N 2 p. 293-298;
K.P. Fedorova1*, I.S. Scharafutdinov1, E.Y. Turbina2, M.I. Bogachev3, O.N. Ilinskaya1, A.R. Kayumov1
C-Terminus of Transcription Factor TnrA from Bacillus subtilis Controls DNA-Binding Domain Activity but Is Not Required for Dimerization1Kazan (Volga region) federal university, Kazan, 420008 Russia
2Voronezh State University, Voronezh, 394006 Russia
3Saint-Petersburg Electrotechnical University «LETI», Saint-Petersburg, 197376 Russia
Received - 2012-08-28; Accepted - 2012-10-02
The transcription factor TnrA, which belongs to the MerR transcription regulators, in Bacillus subtilis controls genes of nitrogen metabolism during nitrogen limiting conditions. As all the DNA-binding proteins, it is active as a dimer in cells, but the dimerization site is still unknown. The multiple alignment of TnrA homologs from other Bacilli allowed to identify the putative dimerization sites. Using the C-terminal truncated TnrA proteins it is established, that, in contrast to other MerR-proteins, the TnrA C-terminus does not participate in dimerization. Surface plasmon resonance has revealed that C-terminus truncations of TnrA do not inactivate its DNA-binding activity. Contrary, increased the affinity towards DNA, confirming that C-terminus controls the DNA-binding activity in a full-length TnrA.
Bacillus subtilis, transcription factor TnrA, dimerization