Helix-Turn-Helix DNA binding domain of the HspR transcription regulator; Helix-turn-helix (HTH) transcription regulator HspR, N-terminal domain. Heat shock protein regulators (HspR) have been shown to regulate expression of specific regulons in response to high temperature or high osmolarity in Streptomyces and Helicobacter, respectively. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the dissimilar C-terminal domains bind specific coactivator molecules.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  14 VYVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLT-EAGVNLEGVRRILELEEEVMELKSE 92
Cdd:cd04766    1 VYVISVAAELSGMHPQTLRLYERLGLLSPSRTDGGTRRYSERDIERLRRIQRLTqELGVNLAGVKRILELEEELAELRAE 80

                         90
                 ....*....|.
gi 918751888  93 IKRIKDSKKEE 103
Cdd:cd04766   81 LDELRARLRRE 91

Helix-Turn-Helix DNA binding domain of the HspR transcription regulator; Helix-turn-helix (HTH) transcription regulator HspR, N-terminal domain. Heat shock protein regulators (HspR) have been shown to regulate expression of specific regulons in response to high temperature or high osmolarity in Streptomyces and Helicobacter, respectively. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the dissimilar C-terminal domains bind specific coactivator molecules.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  14 VYVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLT-EAGVNLEGVRRILELEEEVMELKSE 92
Cdd:cd04766    1 VYVISVAAELSGMHPQTLRLYERLGLLSPSRTDGGTRRYSERDIERLRRIQRLTqELGVNLAGVKRILELEEELAELRAE 80

                         90
                 ....*....|.
gi 918751888  93 IKRIKDSKKEE 103
Cdd:cd04766   81 LDELRARLRRE 91

DNA-binding transcriptional regulator, MerR family [Transcription];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRILELEEEVMElksEIKR 95
Cdd:COG0789    1 IGEVARLTGVSVRTLRYYERIGLLPPpERTEGGYRLYSEEDVERLRFIRRLRELGFSLAEIRELLDLLDDGEE---EVRE 77

                         90
                 ....*....|.
gi 918751888  96 IKDSKKEEVDE 106
Cdd:COG0789   78 LLEEHLAELEA 88

Zn(2+)-responsive transcriptional regulator;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDPK-RTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRILELEEEVMELK-SE 92
Cdd:PRK09514   2 YRIGELAKLAEVTPDTLRFYEKQGLMDPEvRTEGGYRLYTEQDLQRLRFIRRAKQLGFTLEEIRELLSIRLDPEHHTcQE 81

                         90       100       110
                 ....*....|....*....|....*....|....
gi 918751888  93 IKRIKDSKKEEVDE-----THrqYRRDLVPINQA 121
Cdd:PRK09514  82 VKGIVDEKLAEVEAkiaelQH--MRRSLQRLNDA 113

Helix-Turn-Helix DNA binding domain of the HspR transcription regulator; Helix-turn-helix (HTH) transcription regulator HspR, N-terminal domain. Heat shock protein regulators (HspR) have been shown to regulate expression of specific regulons in response to high temperature or high osmolarity in Streptomyces and Helicobacter, respectively. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the dissimilar C-terminal domains bind specific coactivator molecules.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  14 VYVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLT-EAGVNLEGVRRILELEEEVMELKSE 92
Cdd:cd04766    1 VYVISVAAELSGMHPQTLRLYERLGLLSPSRTDGGTRRYSERDIERLRRIQRLTqELGVNLAGVKRILELEEELAELRAE 80

                         90
                 ....*....|.
gi 918751888  93 IKRIKDSKKEE 103
Cdd:cd04766   81 LDELRARLRRE 91

helix_turn_helix, mercury resistance;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 918751888    15 YVISVAAELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRI 79
Cdd:smart00422   1 YTIGEVAKLAGVSVRTLRYYERIGLLPPpIRTEGGYRLYSDEDLERLRFIKRLKELGFSLEEIKEL 66

Helix-Turn-Helix DNA binding domain of MerR-like transcription regulators; Helix-turn-helix (HTH) MerR-like transcription regulator, N-terminal domain. The MerR family transcription regulators have been shown to mediate responses to stress including exposure to heavy metals, drugs, or oxygen radicals in eubacterial and some archaeal species. They regulate transcription of multidrug/metal ion transporter genes and oxidative stress regulons by reconfiguring the spacer between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRILELEEEVMELkSEIK 94
Cdd:cd00592    1 YTIGEVAKLLGVSVRTLRYYEEKGLLPPERSENGYRLYSEEDLERLRLIRRLRELGLSLKEIRELLDARDEELSL-AALL 79

                         90       100
                 ....*....|....*....|.
gi 918751888  95 RIKDSKKEEVDETHRQYRRDL 115
Cdd:cd00592   80 ALLDEKLAELEEKIARLEALL 100

Helix-Turn-Helix DNA binding domain of putative HspR-like transcription regulators; Putative helix-turn-helix (HTH) transcription regulator HspR-like proteins. Unlike the characterized HspR, these proteins have a C-terminal domain with putative metal binding cysteines (MBC). Heat shock protein regulators (HspR) have been shown to regulate expression of specific regulons in response to high temperature or high osmolarity in Streptomyces and Helicobacter, respectively. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the dissimilar C-terminal domains bind specific coactivator molecules.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 918751888  14 VYVISVAAELAGVHPQTLRIYERRGLLDPKRtSGGSRRYSQRDLERLRRISDL-TEAGVNLEGVRRI 79
Cdd:cd04767    1 LYPIGVVAELLNIHPETLRIWERHGLIKPAR-RNGQRLYSNNDLKRLRFIKKLiNEKGLNIAGVKQI 66

Helix-Turn-Helix DNA binding domain of Heavy Metal Resistance transcription regulators; Helix-turn-helix (HTH) heavy metal resistance transcription regulators (HMRTR): MerR1 (mercury), CueR (copper), CadR (cadmium), PbrR (lead), ZntR (zinc), and other related proteins. These transcription regulators mediate responses to heavy metal stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLD-PKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRILELEEEVMELKSEIKR 95
Cdd:cd04770    3 IGELAKAAGVSPDTIRYYERIGLLPpPQRSENGYRLYGEADLARLRFIRRAQALGFSLAEIRELLSLRDDGAAPCAEVRA 82

                         90
                 ....*....|.
gi 918751888  96 IKDSKKEEVDE 106
Cdd:cd04770   83 LLEEKLAEVEA 93

Helix-Turn-Helix DNA binding domain of the MerR1 transcription regulator; Helix-turn-helix (HTH) transcription regulator MerR1. MerR1 transcription regulators, such as Tn21 MerR and Tn501 MerR, mediate response to mercury exposure in eubacteria. These proteins are comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain winged HTH motifs that mediate DNA binding, while the C-terminal domains have three conserved cysteines that define a mercury binding site. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLD-PKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVR 77
Cdd:cd04783    3 IGELAKAAGVNVETIRYYQRRGLLPePPRPEGGYRRYPEETVTRLRFIKRAQELGFTLDEIA 64

Helix-Turn-Helix DNA binding domain of putative transcription regulators from the MerR superfamily; Putative helix-turn-helix (HTH) MerR-like transcription regulators (subgroup 3). Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRI 79
Cdd:cd01282    3 IGELAARTGVSVRSLRYYEEQGLLVPERSANGYRDYDEAAVDRVRQIRRLLAAGLTLEEIREF 65

HTH-type transcriptional regulator MlrA;

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 918751888  13 AVYVISVAAELAGVHPQTLRIYERR-GLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVR 77
Cdd:PRK15043   2 ALYTIGEVALLCDINPVTLRAWQRRyGLLKPQRTDGGHRLFNDADIDRIREIKRWIDNGVQVSKVK 67

Helix-Turn-Helix DNA binding domain of the MerR-like transcription regulators YyaN and YraB; Putative helix-turn-helix (HTH) MerR-like transcription regulators of Bacillus subtilis, YyaN and YraB, and related proteins; N-terminal domain. Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRILELEEEVMELKSEI 93
Cdd:cd01109    1 YTIKEVAEKTGLSADTLRYYEKEGLLPPvKRDENGIRDFTEEDLEWLEFIKCLRNTGMSIKDIKEYAELRREGDSTIPER 80

                         90
                 ....*....|...
gi 918751888  94 KRIKDSKKEEVDE 106
Cdd:cd01109   81 LELLEEHREELEE 93

Helix-Turn-Helix DNA binding domain of the CadR- and PbrR-like transcription regulators; Helix-turn-helix (HTH) CadR- and PbrR-like transcription regulators. CadR and PbrR regulate expression of the cadmium and lead resistance operons, respectively. These proteins are comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the C-terminal domains have three conserved cysteines which comprise a putative metal binding site. Some members in this group have a histidine-rich C-terminal extension. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLD-PKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVR 77
Cdd:cd04785    3 IGELARRTGVNVETIRYYESIGLLPePARTAGGYRLYGAAHVERLRFIRRARDLGFSLEEIR 64

Helix-Turn-Helix DNA binding domain of putative Cfa-like transcription regulators; Putative helix-turn-helix (HTH) MerR-like transcription regulator; conserved, Cfa-like, unknown proteins (~172 a.a.). The N-terminal domain of these proteins appears to be related to the HTH domain of Cfa, a cyclopropane fatty acid synthase. These Cfa-like proteins have a unique C-terminal domain with conserved histidines (motif HXXFX7HXXF). Based on sequence similarity of the N-terminal domains, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRI 79
Cdd:cd04790    2 LTISQLARQFGLSRSTLLYYERIGLLSPsARSESNYRLYGERDLERLEQICAYRSAGVSLEDIRSL 67

Helix-Turn-Helix DNA binding domain of the YfmP transcription regulator; Helix-turn-helix (HTH) transcription regulator, YfmP, and related proteins; N-terminal domain. YfmP regulates the multidrug efflux protein, YfmO, and indirectly regulates the expression of the Bacillus subtilis copZA operon encoding a metallochaperone, CopZ, and a CPx-type ATPase efflux protein, CopA. These proteins belong to the MerR superfamily of transcription regulators that promote expression of several stress regulon genes by reconfiguring the spacer between the -35 and -10 promoter elements. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the dissimilar C-terminal domains bind specific coactivator molecules.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTE 68
Cdd:cd04774    1 YKVDEVAKRLGLTKRTLKYYEEIGLVSPERSEGRYRLYSEEDLKRLERILRLRE 54

Helix-Turn-Helix DNA binding domain of putative MlrA-like transcription regulators; Putative helix-turn-helix (HTH) MlrA-like transcription regulators (subgroup 1). The MlrA protein, also known as YehV, has been shown to control cell-cell aggregation by co-regulating the expression of curli and extracellular matrix production in Escherichia coli and Salmonella typhimurium. These proteins belong to the MerR superfamily of transcription regulators that promote expression of several stress regulon genes by reconfiguring the spacer between the -35 and -10 promoter elements. Their conserved N-terminal domains contain predicted HTH motifs that mediate DNA binding, while the dissimilar C-terminal domains bind specific coactivator molecules. Many MlrA-like proteins in this group appear to lack the long dimerization helix seen in the N-terminal domains of typical MerR-like proteins.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRI 79
Cdd:cd04764    1 YTIKEVSEIIGVKPHTLRYYEKEFNLYIPRTENGRRYYTDEDIELLKKIKTLLEKGLSIKEIKEI 65

Helix-Turn-Helix DNA binding domain of Cfa-like transcription regulators; Putative helix-turn-helix (HTH) MerR-like transcription regulators; the HTH domain of Cfa, a cyclopropane fatty acid synthase, and other related methyltransferases, as well as, the N-terminal domain of a conserved, uncharacterized ~172 a.a. protein. Based on sequence similarity of the N-terminal domain, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 918751888  14 VYVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLE 74
Cdd:cd04775    1 MYTIGQMSRKFGVSRSTLLYYESIGLIPSARSEANYRLYSEADLSRLEKIVFLQAGGLPLE 61

Helix-Turn-Helix DNA binding domain of the Cfa transcription regulator; Putative helix-turn-helix (HTH) MerR-like transcription regulator; the N-terminal domain of Cfa, a cyclopropane fatty acid synthase and other related methyltransferases. Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  14 VYVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNL 73
Cdd:cd04789    1 MYTISELAEKAGISRSTLLYYEKLGLITGTRNANGYRLYPDSDLQRLLLIQQLQAGGLSL 60

MerR family regulatory protein;

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 918751888   17 ISVAAELAGVHPQTLRIYERRGLLD-PKRTSGGSRRY 52
Cdd:pfam00376   2 IGEVAKLLGVSPRTLRYYEKIGLLPpPERTEGGYRRY 38

Second Helix-Turn-Helix DNA binding domain of the regulatory protein TioE; Putative helix-turn-helix (HTH) regulatory protein, TioE, and related proteins. TioE is part of the thiocoraline gene cluster, which is involved in the biosynthesis of the antitumor thiocoraline from the marine actinomycete, Micromonospora. These proteins share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements. Proteins in this family are unique within the MerR superfamily in that they are composed of just two adjacent MerR-like N-terminal domains; this CD mainly contains the C-terminal or second repeat (rpt2) of these tandem MerR-like domain proteins.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLDPKR-TSGGSRRYSQRDLERLRRISDLTEAGVNLEGVR 77
Cdd:cd04773    3 IGELAHLLGVPPSTLRHWEKEGLLSPDRePETGYRVYDPSDVRDARLIHLLRRGGYLLEQIA 64

mercuric resistance operon transcriptional regulator MerR;

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLL-DPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLE 74
Cdd:PRK13752  10 IGVFAKAAGVNVETIRFYQRKGLLpEPDKPYGSIRRYGEADVTRVRFVKSAQRLGFSLD 68

Helix-Turn-Helix DNA binding domain of putative Heavy Metal Resistance transcription regulators; Putative helix-turn-helix (HTH) heavy metal resistance transcription regulators (HMRTR), unknown subgroup. Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to heavy metal stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules, such as, metal ions, drugs, and organic substrates. This subgroup lacks one of the conserved, metal-binding cysteines seen in the MerR1 group.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  21 AELAGVHPQTLRIYERRGLLDPKRTSG-GSRRYSQRDLERLRRISDLTEAGVNLEGVRRIlelEEEVMELKSEIKRIKDS 99
Cdd:cd04787    7 ANAAGVTPDTVRFYTRIGLLRPTRDPVnGYRLYSEKDLSRLRFILSARQLGFSLKDIKEI---LSHADQGESPCPMVRRL 83

                         90
                 ....*....|...
gi 918751888 100 KKEEVDETHRQYR 112
Cdd:cd04787   84 IEQRLAETERRIK 96

Helix-Turn-Helix DNA binding domain of the transcription regulators NolA and AlbR; Helix-turn-helix (HTH) transcription regulators NolA and AlbR, N-terminal domain. In Bradyrhizobium (Arachis) sp. NC92, NolA is required for efficient nodulation of host plants. In Xanthomonas albilineans, AlbR regulates the expression of the pathotoxin, albicidin. These proteins are putatively comprised of distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their conserved N-terminal domains contain predicted winged HTH motifs that mediate DNA binding, while the C-terminal domains are often unrelated and bind specific coactivator molecules. They share the N-terminal DNA binding domain with other transcription regulators of the MerR superfamily that promote transcription by reconfiguring the spacer between the -35 and -10 promoter elements.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 918751888  21 AELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRR 78
Cdd:cd04788    7 ARRTGLSVRTLHHYDHIGLLSPsQRTEGGHRLYDRADIRRLHQIIALRRLGFSLREIGR 65

Helix-Turn-Helix DNA binding domain of putative transcription regulators from the MerR superfamily; Putative helix-turn-helix (HTH) MerR-like transcription regulators (subgroup 6) with at least two conserved cysteines present in the C-terminal portion of the protein. Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRILELEEEVMELKSEIKri 96
Cdd:cd04781    3 IAEVARQSGLPASTLRYYEEKGLIASIGRRGLRRQYDPQVLDRLALIALGRAAGFSLDEIQAMLSHDGKPPIDRQLLK-- 80

                         90
                 ....*....|....
gi 918751888  97 kdSKKEEVDETHRQ 110
Cdd:cd04781   81 --AKAAELDQQIQR 92

HTH-type transcriptional regulator CueR;

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 918751888  17 ISVAAELAGVHPQTLRIYERRGLLDPK-RTSGGSRRYSQRDLERLRRISDLTEAGVNLE 74
Cdd:PRK10227   3 ISDVAKITGLTSKAIRFYEEKGLVTPPmRSENGYRTYTQQHLNELTLLRQARQVGFNLE 61

Helix-Turn-Helix DNA binding domain of putative transcription regulators from the MerR superfamily; Putative helix-turn-helix (HTH) MerR-like transcription regulators (subgroup 2). Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDPKRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVR 77
Cdd:cd04778    2 YRIDDLARAAGTTVRNVRAYQDRGLLPPPRRRGRVAIYNDSHLARLRLINQLLERGYTLAHIA 64

HTH-type transcriptional regulator MerD;

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 918751888  15 YVISVAAELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRI 79
Cdd:PRK13749   4 YTVSRLALDAGVSVHIVRDYLLRGLLRPvACTTGGYGLFDDAALQRLCFVRAAFEAGIGLDALARL 69

Helix-Turn-Helix DNA binding domain of putative transcription regulators from the MerR superfamily; Putative helix-turn-helix (HTH) MerR-like transcription regulators (subgroup 7) with a conserved cysteine present in the C-terminal portion of the protein. Based on sequence similarity, these proteins are predicted to function as transcription regulators that mediate responses to stress in eubacteria. They belong to the MerR superfamily of transcription regulators that promote transcription of various stress regulons by reconfiguring the operator sequence located between the -35 and -10 promoter elements. A typical MerR regulator is comprised of two distinct domains that harbor the regulatory (effector-binding) site and the active (DNA-binding) site. Their N-terminal domains are homologous and contain a DNA-binding winged HTH motif, while the C-terminal domains are often dissimilar and bind specific coactivator molecules such as metal ions, drugs, and organic substrates.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 918751888  21 AELAGVHPQTLRIYERRGLLDP-KRTSGGSRRYSQRDLERLRRISDLTEAGVNLEGVRRI 79
Cdd:cd04786    7 AKRSGMAASRIRFYEAEGLLSSvERSANGYRDYPPETVWVLEIISSAQQAGFSLDEIRQL 66