>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=96.88  E-value=0.0014  Score=41.92  Aligned_cols=45  Identities=22%  Similarity=0.286  Sum_probs=40.2

Q ss_pred             CCCCHHHHHHHHHHCCCCCCCHHHHHHHHCCCCCCCCCCHHHHHHHHHHHHHHH
Q ss_conf             464116889998718997378999999871887777753036678999885110
Q gi|254780893|r  150 LTGKEYQMIELLSLRKNTTLTKEMFLNHLYDGRDEPEVKIIDVFICKLRKKLSN  203 (236)
Q Consensus       150 LT~~E~~lL~~L~~~~g~vvsr~~i~~~vw~~~~~~~~~tld~~I~rLRkKL~~  203 (236)
T Consensus         1 LT~rE~~il~~~~~--G--~s~~eIA~~L-----~is~~TV~~~~~~i~~Kl~~   45 (57)
T cd06170           1 LTPREREVLRLLAE--G--KTNKEIADIL-----GISEKTVKTHLRNIMRKLGV   45 (57)
T ss_pred             CCHHHHHHHHHHHC--C--CCHHHHHHHH-----CCCHHHHHHHHHHHHHHHCC
T ss_conf             98899999999980--7--9999999998-----97899999999999998689