>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=96.80  E-value=0.0046  Score=39.98  Aligned_cols=44  Identities=20%  Similarity=0.335  Sum_probs=37.6

Q ss_pred             CCHHHHHHHHHHHCCCCCCCHHHHHHHHCCCHHHHHHHHHHHHHHHH
Q ss_conf             99999999999827888889899999977899999999999999999
Q gi|254780611|r  235 LNPRERRIFEARRLQENPVTLENLSSEFEVSRERVRQIEARAFKKVQ  281 (302)
Q Consensus       235 L~~rEr~II~~ry~~~~~~Tl~EIa~~lgiS~eRVrQI~~~AL~kLR  281 (302)
T Consensus         1 LT~rE~~il~~~~---~G~s~~eIA~~L~is~~TV~~~~~~i~~Kl~   44 (57)
T cd06170           1 LTPREREVLRLLA---EGKTNKEIADILGISEKTVKTHLRNIMRKLG   44 (57)
T ss_pred             CCHHHHHHHHHHH---CCCCHHHHHHHHCCCHHHHHHHHHHHHHHHC
T ss_conf             9889999999998---0799999999989789999999999999868