phosphoacceptor receiver (REC) domain of NarL (Nitrate/Nitrite response regulator L) family response regulators; The NarL family is one of the more abundant families of DNA-binding response regulators (RRs). Members of the NarL family contain a REC domain and a helix-turn-helix (HTH) DNA-binding output domain, with a majority of members containing a LuxR-type HTH domain. They function as transcriptional regulators. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:cd17535    21 EPDIEVVGEAADGEEALALLRELRPDVVLMDLSMPGMDGIEALRRLRRRYPDLKVIVLTAHDDPEYVLRALKAGAAGYLL 100

                          90
                  ....*....|
gi 1812104277  88 KTSTAHEIAD 97
Cdd:cd17535   101 KDSSPEELIE 110

phosphoacceptor receiver (REC) domain of NarL (Nitrate/Nitrite response regulator L) family response regulators; The NarL family is one of the more abundant families of DNA-binding response regulators (RRs). Members of the NarL family contain a REC domain and a helix-turn-helix (HTH) DNA-binding output domain, with a majority of members containing a LuxR-type HTH domain. They function as transcriptional regulators. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:cd17535    21 EPDIEVVGEAADGEEALALLRELRPDVVLMDLSMPGMDGIEALRRLRRRYPDLKVIVLTAHDDPEYVLRALKAGAAGYLL 100

                          90
                  ....*....|
gi 1812104277  88 KTSTAHEIAD 97
Cdd:cd17535   101 KDSSPEELIE 110

transcriptional regulator NarL; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   9 EDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAiLKDCP-KAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:PRK10651   30 PDITVVGEASNGEQGIELAESLDPDLILLDLNMPGMNGLETLDK-LREKSlSGRIVVFSVSNHEEDVVTALKRGADGYLL 108

                  .
gi 1812104277  88 K 88
Cdd:PRK10651  109 K 109

sporulation transcription factor Spo0A; Spo0A, the stage 0 sporulation protein A, is a transcription factor critical for the initiation of sporulation. It contains a response regulator receiver domain (pfam00072). In Bacillus subtilis, it works together with response regulator Spo0F and the phosphotransferase Spo0B, both of which are missing from at least some sporulating species and thus not part of the endospore forming bacteria minimal gene set. Spo0A, however, is universal among endospore-forming species. [Cellular processes, Sporulation and germination]

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   4 YFACQEDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAI--LKDCPKAKIIIVTSFIDDEKVYPAIEAG 81
Cdd:TIGR02875  21 YLAAQPDMEVVGVAHNGVDALELIKEQQPDVVVLDIIMPHLDGIGVLEKLneIELSARPRVIMLSAFGQEKITQRAVALG 100

                  ....*..
gi 1812104277  82 AAGYLLK 88
Cdd:TIGR02875 101 ADYYVLK 107

phosphoacceptor receiver (REC) domain of NarL (Nitrate/Nitrite response regulator L) family response regulators; The NarL family is one of the more abundant families of DNA-binding response regulators (RRs). Members of the NarL family contain a REC domain and a helix-turn-helix (HTH) DNA-binding output domain, with a majority of members containing a LuxR-type HTH domain. They function as transcriptional regulators. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:cd17535    21 EPDIEVVGEAADGEEALALLRELRPDVVLMDLSMPGMDGIEALRRLRRRYPDLKVIVLTAHDDPEYVLRALKAGAAGYLL 100

                          90
                  ....*....|
gi 1812104277  88 KTSTAHEIAD 97
Cdd:cd17535   101 KDSSPEELIE 110

phosphoacceptor receiver (REC) domain of chemotaxis protein CheY; The chemotaxis response regulator CheY contains a stand-alone REC domain. Chemotaxis is a behavior known for motile bacteria that directs their movement in response to chemical gradients. CheY is involved in transmitting sensory signals from chemoreceptors to the flagellar motors. Phosphorylated CheY interacts with the flagella switch components FliM and FliY, which causes counterclockwise rotation of the flagella, resulting in smooth swimming. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:cd17542    22 KAGYEVVGEAANGEEAVEKYKELKPDLVTMDITMPEMDGIEALKEIKKIDPNAKVIMCSAMGQEEMVKEAIKAGAKDFIV 101

                  .
gi 1812104277  88 K 88
Cdd:cd17542   102 K 102

phosphoacceptor receiver (REC) domain of YesN and related helix-turn-helix containing response regulators; This family is composed of uncharacterized response regulators that contain a REC domain and a AraC family helix-turn-helix (HTH) DNA-binding output domain, including Bacillus subtilis uncharacterized transcriptional regulatory protein YesN and Staphylococcus aureus uncharacterized response regulatory protein SAR0214. YesN is a member of the two-component regulatory system YesM/YesN and SAR0214 is a member of the probable two-component regulatory system SAR0215/SAR0214. Also included in this family is the AlgR-like group of LytTR/AlgR family response, which includes Pseudomonas aeruginosa positive alginate biosynthesis regulatory protein AlgR and Bacillus subtilis sensory transduction protein LytT, among others. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277  10 DMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLKT 89
Cdd:cd17536    24 GFEVVGEAENGEEALELIEEHKPDIVITDIRMPGMDGLELIEKIRELYPDIKIIILSGYDDFEYAQKAIRLGVVDYLLKP 103

                  ....*...
gi 1812104277  90 STAHEIAD 97
Cdd:cd17536   104 VDEEELEE 111

transcriptional regulator NarL; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   9 EDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAiLKDCP-KAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:PRK10651   30 PDITVVGEASNGEQGIELAESLDPDLILLDLNMPGMNGLETLDK-LREKSlSGRIVVFSVSNHEEDVVTALKRGADGYLL 108

                  .
gi 1812104277  88 K 88
Cdd:PRK10651  109 K 109

phosphoacceptor receiver (REC) domain of Nitrate/Nitrite response regulator L (NarL); Nitrate/nitrite response regulator protein NarL contains an N-terminal REC domain and a C-terminal LuxR family helix-turn-helix (HTH) DNA-binding output domain. Escherichia coli NarL activates the expression of the nitrate reductase (narGHJI) and formate dehydrogenase-N (fdnGHI) operons, and represses the transcription of the fumarate reductase (frdABCD) operon in response to a nitrate/nitrite induction signal. Phosphorylation of the NarL REC domain releases the C-terminal HTH output domain that subsequently binds specific DNA promoter sites to repress or activate gene expression. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1812104277  10 DMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd19931    23 DFTVVGEASSGEEGIELAERLDPDLILLDLNMKGMSGLDTLKALREEGVSARIVILTVSDAEDDVVTALRAGADGYLLK 101

Response regulator receiver domain; This domain receives the signal from the sensor partner in bacterial two-component systems. It is usually found N-terminal to a DNA binding effector domain.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEViGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:pfam00072  20 KEGYVV-AEADDGKEALELLKEERPDLILLDINMPGMDGLELLKRIRRRDPTTPVIILTAHGDEDDAVEALEAGADDFLS 98

                  ....*...
gi 1812104277  88 KTSTAHEI 95
Cdd:pfam00072  99 KPFDPDEL 106

phosphoacceptor receiver (REC) domain of response regulators (RRs) and pseudo response regulators (PRRs); Two-component systems (TCSs) involving a sensor and a response regulator are used by bacteria to adapt to changing environments. Processes regulated by two-component systems in bacteria include sporulation, pathogenicity, virulence, chemotaxis, and membrane transport. Response regulators (RRs) share the common phosphoacceptor REC domain and different effector/output domains such as DNA, RNA, ligand-binding, protein-binding, or enzymatic domains. Response regulators regulate transcription, post-transcription or post-translation, or have functions such as methylesterases, adenylate or diguanylate cyclase, c-di-GMP-specific phosphodiesterases, histidine kinases, serine/threonine protein kinases, and protein phosphatases, depending on their output domains. The function of some output domains are still unknown. TCSs are found in all three domains of life - bacteria, archaea, and eukaryotes, however, the presence and abundance of particular RRs vary between the lineages. Archaea encode very few RRs with DNA-binding output domains; most are stand-alone REC domains. Among eukaryotes, TCSs are found primarily in protozoa, fungi, algae, and green plants. REC domains function as phosphorylation-mediated switches within RRs, but some also transfer phosphoryl groups in multistep phosphorelays.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277  8 QEDMEVIgEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLL 87
Cdd:cd00156   19 REGYEVD-TAADGEEALELLREERPDLVLLDLMMPGMDGLELLRKLRELPPDIPVIVLTAKADEEDAVRALELGADDYLV 97

                 .
gi 1812104277 88 K 88
Cdd:cd00156   98 K 98

phosphoacceptor receiver (REC) domain of PdtaR and similar proteins; This subfamily includes Mycobacterium tuberculosis PdtaR, also called Rv1626, and similar proteins containing a REC domain and an ANTAR (AmiR and NasR transcription antitermination regulators) RNA-binding output domain. PdtaR is a response regulator that acts at the level of transcriptional antitermination and is a member of the PdtaR/PdtaS two-component regulatory system. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1812104277  12 EVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPkAKIIIVTSFIDDEKVYPAIEAGAAGYLLKT 89
Cdd:cd19932    26 EVVGEASDGEEAVELAKKHKPDLVIMDVKMPRLDGIEAAKIITSENI-APIVLLTAYSQQDLVERAKEAGAMAYLVKP 102

DNA-binding response regulator, LytR/AlgR family [Transcription, Signal transduction mechanisms];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   9 EDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFidDEKVYPAIEAGAAGYLLK 88
Cdd:COG3279    25 PDLEVVGEASNGEEALELLEEHKPDLVFLDIQMPGLDGFELARQLRELDPPPPIIFTTAY--DEYALEAFEVNAVDYLLK 102

Two-component response regulator, PleD family, consists of two REC domains and a diguanylate cyclase (GGDEF) domain [Signal transduction mechanisms, Transcription];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIgEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAIlKDCPKAK---IIIVTSFIDDEKVYPAIEAGAAG 84
Cdd:COG3706    23 AAGYEVV-EAADGEEALELLQEHRPDLILLDLEMPDMDGLELCRRL-RADPRTAdipIIFLTALDDEEDRARALEAGADD 100

                  ....
gi 1812104277  85 YLLK 88
Cdd:COG3706   101 YLTK 104

nitrate/nitrite response regulator protein NarP;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1812104277  12 EVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLKTS 90
Cdd:PRK10403   33 EVVAEAGDGASAIDLANRLDPDVILLDLNMKGMSGLDTLNALRRDGVTAQIIILTVSDASSDVFALIDAGADGYLLKDS 111

Response regulator c-di-GMP phosphodiesterase, RpfG family, contains REC and HD-GYP domains [Signal transduction mechanisms];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1812104277  16 EAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAI--LKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:COG3437    35 TAESGEEALELLLEAPPDLILLDVRMPGMDGFELLRLLraDPSTRDIPVIFLTALADPEDRERALEAGADDYLTK 109

phosphoacceptor receiver (REC) domain of transcriptional regulatory protein GlnL and similar proteins; Bacillus subtilis GlnL is part of the GlnK-GlnL (formerly YcbA-YcbB) two-component system that positively regulates the expression of the glsA-glnT (formerly ybgJ-ybgH) operon in response to glutamine. It contains a REC domain and a DNA-binding output domain. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1812104277  12 EVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd17565    25 EVVGEADNGAQAYDEILFLQPDIVLIDLLMPGMDGIQLVRKLKDTGSNGKFIMISQVSDKEMIGKAYQAGIEFFINK 101

phosphoacceptor receiver (REC) domain of modulated diguanylate cyclase and similar domains; This groups includes a modulated diguanylate cyclase containing a PAS sensor domain from Desulfovibrio desulfuricans G20. Members of this group contain N-terminal REC domains and various output domains including the GGDEF, histidine kinase, and helix-turn-helix (HTH) DNA binding domains. Also included in this family is Mycobacterium tuberculosis PdtaR, a transcriptional antiterminator that contains a REC domain and an ANTAR RNA-binding output domain. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277  12 EVIGEAENGRKGYEKAMALRPDVILMDLVME-EMDGIESTKAILK--DCPkakIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd17534    26 EVVGIADSGEEAIELAEENKPDLILMDINLKgDMDGIEAAREIREkfDIP---VIFLTAYSDEETLERAKETNPYGYLVK 102

two component system response regulator;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1812104277  12 EVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLKTS 90
Cdd:PRK15369   30 KIVGQVDNGLEVYNACRQLEPDIVILDLGLPGMNGLDVIPQLHQRWPAMNILVLTARQEEHMASRTLAAGALGYVLKKS 108

Two-component response regulator, AmiR/NasT family, consists of REC and RNA-binding antiterminator (ANTAR) domains [Signal transduction mechanisms, Transcription];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1812104277  12 EVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAkIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:COG3707    29 EVVAEAADGEDAVELVRELKPDLVIVDIDMPDRDGLEAARQISEERPAP-VILLTAYSDPELIERALEAGVSAYLVK 104

phosphoacceptor receiver (REC) domain of LytTR/AlgR family response regulators similar to AlgR; Members of the LytTR/AlgR family of response regulators contain a REC domain and a unique LytTR DNA-binding output domain that lacks the helix-turn-helix motif and consists mostly of beta-strands. Transcriptional regulators with the LytTR-type output domains are involved in biosynthesis of extracellular polysaccharides, fimbriation, expression of exoproteins, including toxins, and quorum sensing. Included in this AlgR-like group of LytTR/AlgR family response regulators are Streptococcus agalactiae sensory transduction protein LytR, Pseudomonas aeruginosa positive alginate biosynthesis regulatory protein AlgR, Bacillus subtilis sensory transduction protein LytT, and Escherichia coli transcriptional regulatory protein BtsR, which are members of two-component regulatory systems. LytR and LytT are components of regulatory systems that regulate genes involved in cell wall metabolism. AlgR positively regulates the algD gene, which codes for a GDP-mannose dehydrogenase, a key enzyme in the alginate biosynthesis pathway. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1812104277  10 DMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFidDEKVYPAIEAGAAGYLLK 88
Cdd:cd17532    23 DIEIVGEAENGEEALEAIEELKPDVVFLDIQMPGLDGLELAKKLSKLAKPPLIVFVTAY--DEYAVEAFELNAVDYLLK 99

phosphoacceptor receiver (REC) domain of cyclic di-GMP phosphodiesterase PA4781 and similar domains; Pseudomonas aeruginosa cyclic di-GMP phosphodiesterase PA4781 contains an N-terminal REC domain and a C-terminal catalytic HD-GYP domain, characteristics of RpfG family response regulators. PA4781 is involved in cyclic di-3',5'-GMP (c-di-GMP) hydrolysis/degradation in a two-step reaction via the linear intermediate pGpG to produce GMP. Its unphosphorylated REC domain prevents accessibility of c-di-GMP to the active site. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1812104277  17 AENGRKGYEKAMALRPDVILMDLVMEEMDGIEsTKAILKDCPKAK---IIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd19920    28 ATDGQQALQRAQAEPPDLILLDVMMPGMDGFE-VCRRLKADPATRhipVIFLTALTDTEDKVKGFELGAVDYITK 101

phosphoacceptor receiver (REC) domain of chemotaxis response regulator CheY3 and similar CheY family proteins; CheY family chemotaxis response regulators (RRs) comprise about 17% of bacterial RRs and almost half of all RRs in archaea. This subfamily contains Vibrio cholerae CheY3, Escherichia coli CheY, and similar CheY family RRs. CheY proteins control bacterial motility and participate in signaling phosphorelays and in protein-protein interactions. CheY RRs contain only the REC domain with no output/effector domain. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277  14 IGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAI-----LKDCPkakIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd19923    28 VEEAEDGVDALEKLKAGGFDFVITDWNMPNMDGLELLKTIradgaLSHLP---VLMVTAEAKKENVIAAAQAGVNNYIVK 104

                  ....
gi 1812104277  89 TSTA 92
Cdd:cd19923   105 PFTA 108

first (D1) phosphoacceptor receiver (REC) domain of response regulator PleD and similar domains; PleD contains a REC domain (D1) with the phosphorylatable aspartate, a REC-like adaptor domain (D2), and the enzymatic diguanylate cyclase (DGC) domain, also called the GGDEF domain according to a conserved sequence motif, as its output domain. The GGDEF-containing PleD response regulators are global regulators of cell metabolism in some important human pathogens. This model describes D1 of PleD and similar domains. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIgEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKaILKDCPKAK---IIIVTSFIDDEKVYPAIEAGAAG 84
Cdd:cd17538    21 AEGYEVL-TADSGQEALALAEEELPDLILLDVMMPGMDGFEVCR-RLKEDPETRhipVIMITALDDREDRIRGLEAGADD 98

                  ....
gi 1812104277  85 YLLK 88
Cdd:cd17538    99 FLSK 102

phosphoacceptor receiver (REC) domain of chemotaxis response regulator CheY4 and similar CheY family proteins; CheY family chemotaxis response regulators (RRs) comprise about 17% of bacterial RRs and almost half of all RRs in archaea. This subfamily contains Vibrio cholerae CheY4 and similar CheY family RRs. CheY proteins control bacterial motility and participate in signaling phosphorelays and in protein-protein interactions. CheY RRs contain only the REC domain with no output/effector domain. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277  12 EVIgEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAiLKDCPKAK---IIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd17562    26 EVV-EAADGRDALSKAQSKKFDLIITDQNMPNMDGIELIKE-LRKLPAYKftpILMLTTESSDEKKQEGKAAGATGWLVK 103

sigma-54-dependent response regulator transcription factor ZraR;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1812104277  17 AENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:PRK10365   35 ANSGRQALEQVREQVFDLVLCDVRMAEMDGIATLKEIKALNPAIPVLIMTAYSSVETAVEALKTGALDYLIK 106

phosphoacceptor receiver (REC) domain of uncharacterized hybrid sensor histidine kinase/response regulators; Typically, two-component regulatory systems (TCSs) consist of a sensor (histidine kinase) that responds to specific input(s) by modifying the output of a cognate response regulator (RR). TCSs allow organisms to sense and respond to changes in environmental conditions. Hybrid sensor histidine kinase/response regulators contain all the elements of a classical TCS in a single polypeptide chain. RRs share the common phosphoacceptor REC domain and different effector/output domains such as DNA, RNA, ligand-binding, protein-binding, or enzymatic domains. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1812104277  17 AENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAI-----LKDCPkakIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd17598    28 ARNGREALAMLAEHRPTLVISDIVMPEMDGYELCRKIksdpdLKDIP---VILLTTLSDPRDVIRGLECGADNFITK 101

phosphoacceptor receiver (REC) domain of Thermotoga maritima response regulator TrrA and similar domains; Thermotoga maritima contains a two-component signal transduction system (TCS) composed of the ThkA sensory histidine kinase (HK) and its cognate response regulator (RR) TrrA; the specific function of the system is unknown. TCSs couple environmental stimuli to adaptive responses. TrrA is a stand-alone RR containing only a REC domain with no output/effector domain. The REC domain itself functions as an effector domain. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1812104277  17 AENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAagYLLKTSTAHEI 95
Cdd:cd17554    30 AGNGEEALEKLESEDPDLVILDIKMPGMDGLETLRKIREKKPDLPVIICTAYSEYKSDFSSWAADA--YVVKSSDLTEL 106

phosphoacceptor receiver (REC) domain of uncharacterized response regulators containing a CheC domain; This subfamily is composed of uncharacterized proteins containing an N-terminal REC domain and a C-terminal CheC domain that may function as the output/effector domain of a response regulator. CheC is a CheY-P phosphatase, affecting the level of phosphorylated CheY which controls the sense of flagella rotation and determine swimming behavior of chemotactic bacteria. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277  14 IGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLKTSTAH 93
Cdd:cd17593    28 ITFAENGEEALEILREGRIDVLFLDLTMPVMDGYEVLEALPVEQLETKVIVVSGDVQPEAKERVLELGALAFLKKPFDPE 107

                  ....
gi 1812104277  94 EIAD 97
Cdd:cd17593   108 KLAQ 111

phosphoacceptor receiver (REC) domain of cyanobacterial phytochrome response regulator Rcp and similar domains; This family is composed of response regulators (RRs) that are members of phytochrome-associated, light-sensing two-component signal transduction pathways such as Synechocystis sp. Rcp1, Tolypothrix sp. RcpA, and Agrobacterium tumefaciens bacteriophytochrome response regulator AtBRR. They are stand-alone RRs containing only a REC domain with no output/effector domain. The REC domain itself functions as an effector domain. Also included in this family us Methanosaeta harundinacea methanogenesis regulatory protein FilR2, also a stand-alone RR. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1812104277  25 EKAMALRPDVILMDLVMEEMDGIESTKAI-----LKDCPkakIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd17557    46 EYADAPRPDLILLDLNMPRMDGFEVLREIkadpdLRRIP---VVVLTTSDAEEDIERAYELGANSYIVK 111

phosphoacceptor receiver (REC) domain of citrate family two-component system response regulators; This family includes Lactobacillus paracasei MaeR, Escherichia coli DcuR and DpiA, Klebsiella pneumoniae CitB, as well as Bacillus DctR, MalR, and CitT. These are all response regulators of two-component systems (TCSs) from the citrate family, and are involved in the transcriptional regulation of genes associated with L-malate catabolism (MaeRK), citrate-specific fermentation (DpiAB, CitAB), plasmid inheritance (DpiAB), anaerobic fumarate respiratory system (DcuRS), and malate transport/utilization (MalKR). REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1812104277  13 VIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd19925    28 VIGTAGTGEEALKLLKERQPDLILLDIYLPDGNGLDLLRELRAAGHDVDVIVVTAANDVETVREALRLGVVDYLIK 103

hybrid sensory histidine kinase BarA; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1812104277   8 QEDMEVIGEAENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILK-----DCPkakIIIVTSF-IDDEKVYpAIEAG 81
Cdd:PRK11107  688 EEQVEHVVLCDSGHQAVEQAKQRPFDLILMDIQMPGMDGIRACELIRQlphnqNTP---IIAVTAHaMAGERER-LLSAG 763

                  ....*..
gi 1812104277  82 AAGYLLK 88
Cdd:PRK11107  764 MDDYLAK 770

phosphoacceptor receiver (REC) domain of Brucella abortus CpdR and CckA, and similar domains; Two-component systems (TCSs), consisting of a sensor and a response regulator, are used by bacteria to adapt to changing environments. Processes regulated by TCSs in bacteria include sporulation, pathogenicity, virulence, chemotaxis and membrane transport. Response regulators share the common phosphoacceptor REC domain and differ output domains such as DNA, RNA, ligand, and protein-binding, or enzymatic domain. CpdR is a stand-alone REC protein. CckA is a sensor histidine kinase containing N-terminal PAS domains and a C-terminal REC domain. CpdR and CckA are components of a regulatory phosphorelay system (composed of CckA, ChpT, CtrA and CpdR) that controls Brucella abortus cell growth, division, and intracellular survival inside mammalian host cells. CckA autophosphorylates in the presence of ATP and transfers a phosphoryl group to the conserved aspartic acid residue on its C-terminal REC domain, which is relayed to the ChpT phosphotransferase. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1812104277  16 EAENGRKGYEKAMALRP-DVILMDLVMEEMDGIESTKAILKDCPKAKIIIVTSFIDDEKVYPAIEAGAAGYLLK 88
Cdd:cd18160    28 EAESGAEALEKLQQGKDiDIVVTDIVMPEMDGIELAREARKIDPDVKILFISGGAAAAPELLSDAVGDNATLKK 101

second phosphoacceptor receiver (REC) domain of Dictyostelium discoideum hybrid signal transduction histidine kinase D and similar domains; Dictyostelium discoideum hybrid signal transduction histidine kinase D (DhkD) is a large protein that contains two histidine kinase (HK) and two REC domains on the intracellular side of a single pass transmembrane domain, and extracellular PAS and PAC domains that likely are involved in ligand binding. This model represents the second REC domain and similar domains. DhkD activates the cAMP phosphodiesterase RegA to ensure proper prestalk and prespore patterning, tip formation, and the vertical elongation of the mound into a finger, in Dictyostelium discoideum. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1812104277  17 AENGRKGYEKAMALRPDVILMDLVMEEMDGIESTKAILKDCPKAKIIIV--TSFIDDEKVYPAIEAG 81
Cdd:cd17580    28 AHSGEEALEAAQRFRPDVILSDIGMPGMDGYELARRLRELPWLANTPAIalTGYGQPEDRERALEAG 94

phosphoacceptor receiver (REC) domain of CpxR-like OmpR family response regulators; CpxR is part of the CpxA/CpxR two-component regulatory system that mediates envelope stress responses that is key for virulence and antibiotic resistance in several Gram negative pathogens. CpxR is a transcription factor/response regulator that controls the expression of numerous genes, including those of the classical porins OmpF and OmpC. It belongs to the OmpR family of DNA-binding response regulators that contain N-terminal receiver (REC) and C-terminal DNA-binding winged helix-turn-helix effector domains. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.