>cd06170 LuxR_C_like C-terminal DNA-binding domain of LuxR-like proteins. This domain contains a helix-turn-helix motif and binds DNA. Proteins belonging to this group are response regulators; some act as transcriptional activators, others as transcriptional repressors. Many are active as homodimers. Many are two domain proteins in which the DNA binding property of the C-terminal DNA binding domain is modulated by modifications of the N-terminal domain. For example in the case of Lux R which participates in the regulation of gene expression in response to fluctuations in cell-population density (quorum-sensing), a signaling molecule, the pheromone Acyl HSL (N-acyl derivatives of homoserine lactone), binds to the N-terminal domain and leads to LuxR dimerization. For others phophorylation of the N-terminal domain leads to multimerization, for example Escherichia coli NarL and Sinorhizobium melilot FixJ. NarL controls gene expression of many respiratory-related operons when environmental

Probab=94.61  E-value=0.15  Score=31.10  Aligned_cols=53  Identities=28%  Similarity=0.433  Sum_probs=47.0

Q ss_pred             CCHHHHHHHHHHHCCCCCCCCCHHHHHHHHCCCHHHHHHHHHHHHHHHCCHHHHHHHH
Q ss_conf             9988999999981879867468899989966789999999999999832967778756
Q gi|254780289|r  620 LTPREERVLRMRFGIGMNTDHTLEEVGKQFCVTRERIRQIEAKAIRKLKHPSRSKKLR  677 (682)
Q Consensus       620 l~~re~~v~~~r~g~~~~~~~tl~e~~~~~~~~~er~rqi~~~a~~~l~~~~~~~~l~  677 (682)
T Consensus         1 LT~rE~~il~~~-----~~G~s~~eIA~~L~is~~TV~~~~~~i~~Kl~~~~r~elv~   53 (57)
T cd06170           1 LTPREREVLRLL-----AEGKTNKEIADILGISEKTVKTHLRNIMRKLGVKSRTQLVA   53 (57)
T ss_pred             CCHHHHHHHHHH-----HCCCCHHHHHHHHCCCHHHHHHHHHHHHHHHCCCCHHHHHH
T ss_conf             988999999999-----80799999999989789999999999999868999999999