>cd06275 PBP1_PurR Ligand-binding domain of purine repressor, PurR, which functions as the master regulatory protein of de novo purine nucleotide biosynthesis in Escherichia coli. Ligand-binding domain of purine repressor, PurR, which functions as the master regulatory protein of de novo purine nucleotide biosynthesis in Escherichia coli. This dimeric PurR belongs to the LacI-GalR family of transcription regulators and is activated to bind to DNA operator sites by initially binding either of high affinity corepressors, hypoxanthine or guanine. PurR is composed of two functional domains: aan N-terminal HTH (helix-turn-helix) domain, which is responsible for the DNA-binding specificity, and a C-terminal ligand-binding domain, which is homologous to the sugar-binding domain of ABC-type transport systems that contain the type I periplasmic binding protein-like fold. As also observed in the periplasmic binding proteins, the C-terminal domain of the purine transcription repressor undergoes a

Probab=95.52 E-value=0.16 Score=30.50 Aligned_cols=126 Identities=11% Similarity=0.039 Sum_probs=76.8 Q ss_pred CCEEEEEEECHHHHHHHHHHHHHHHHHHHCCCCEEEEE-HHHHHHHHHHHHHHHHHHHCCCCCCEEEEEEEEECCCCCHH Q ss_conf 87179998031289999999999999998799555553-00144226999999863311378535665412000665246 Q gi|254780346|r 5 IPHVLIIEARFYENLSAMLFEGCVNVLHSRAVQWSSIV-TPGVLEIPAAVSMVMNAKTRSVTYDGIIVLGVVMRGKTAHC 83 (149) Q Consensus 5 ~~kI~IV~s~~~~~i~~~ll~ga~~~l~~~~~~~~~i~-VPGa~EiP~a~~~~~~~~~~~~~~D~vIaLG~VIkGeT~H~ 83 (149) T Consensus 117 ~~~i~~i~~~~~~~~~~~R~~Gf~~al~~~~i~~~~~~i~~~~~~~~~~~~~~~~~l~~~~~~~aii~~----------~ 186 (269) T cd06275 117 HRRIGCITGPLEKAPAQQRLAGFRRAMAEAGLPVNPGWIVEGDFECEGGYEAMQRLLAQPKRPTAVFCG----------N 186 (269) T ss_pred CCEEEECCCCCCCHHHHHHHHHHHHHHHHCCCCCCHHHHCCCCCCHHHHHHHHHHHHHHCCCCCEEECC----------C T ss_conf 971775569977716999999999999985999765550367777688999999999708996612318----------7 Q ss_pred HHHHHHHHHHHHHHHHHCCCCCEEEEECCCCHHHHHHHH------CCCCCCCHHHHHHHHHHHHH Q ss_conf 789999999999999743997056542558899999950------65657456999999999999 Q gi|254780346|r 84 DVIAHAVTRGLVDLSINGSLPIGNGIVVVDSEQQAFDRV------SPSHLDRGGCAARSALAMIE 142 (149) Q Consensus 84 e~I~~~v~~gl~~lsl~~~~PI~~gILt~~n~~QA~~R~------~~~~~nkG~eaa~Aal~mi~ 142 (149) T Consensus 187 d~~A~g~~~~l~~~gi--~vP~di~vvgfd~~~~~~~~~p~ltti~q~~~~~g~~a~~~L~~~i~ 249 (269) T cd06275 187 DLMAMGALCAAQEAGL--RVPQDLSIIGYDDIELARYFSPPLTTIHQPKDRLGELAVNMLLERIK 249 (269) T ss_pred HHHHHHHHHHHHHCCC--CCCCCCEEEEECCHHHHHHCCCCEEEEECCHHHHHHHHHHHHHHHHC T ss_conf 4999999999998088--78998679987787999833898589961999999999999999966

HHsearch alignment for GI: 254780346 and conserved domain: cd06275