phosphoacceptor receiver (REC) domain of type A Arabidopsis response regulators (ARRs) and similar proteins; Type-A response regulators of Arabidopsis (ARRs) are involved in cytokinin signaling, which involves a phosphorelay cascade by histidine kinase receptors (AHKs), histidine phosphotransfer proteins (AHPs) and downstream ARRs. Cytokinin is a plant hormone implicated in many growth and development processes including shoot organogenesis, leaf senescence, sink/source relationships, vascular development, lateral bud release, and photomorphogenic development. Type-A ARRs function downstream of and are regulated by type-B ARRs, which are a class of MYB-type transcription factors. As primary cytokinin response genes, type-A ARRs act as redundant negative feedback regulators of cytokinin signaling by inactivating the phosphorelay. ARRs are divided into two groups, type-A and -B, according to their sequence and domain structure. Type-A ARRs are similar in domain structure to CheY, in that they lack a typical output domain and only contain a stand-alone receiver (REC) 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSE----------PNVSMIITDYWMPEMTGYELLKKVKESSK 99
Cdd:cd17581     1 VLAVDDSLVDRKVIERLLRISSCRVTAVDSGKRALEFLGLEdeedssnfnePKVNMIITDYCMPGMTGYDLLKKVKESSA 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|..
gi 2445448931 100 LKKIPVVIMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRL 141
Cdd:cd17581    81 LKEIPVVIMSSENIPTRISRCLEEGAEDFLLKPVKLADVKRL 122

phosphoacceptor receiver (REC) domain of type A Arabidopsis response regulators (ARRs) and similar proteins; Type-A response regulators of Arabidopsis (ARRs) are involved in cytokinin signaling, which involves a phosphorelay cascade by histidine kinase receptors (AHKs), histidine phosphotransfer proteins (AHPs) and downstream ARRs. Cytokinin is a plant hormone implicated in many growth and development processes including shoot organogenesis, leaf senescence, sink/source relationships, vascular development, lateral bud release, and photomorphogenic development. Type-A ARRs function downstream of and are regulated by type-B ARRs, which are a class of MYB-type transcription factors. As primary cytokinin response genes, type-A ARRs act as redundant negative feedback regulators of cytokinin signaling by inactivating the phosphorelay. ARRs are divided into two groups, type-A and -B, according to their sequence and domain structure. Type-A ARRs are similar in domain structure to CheY, in that they lack a typical output domain and only contain a stand-alone receiver (REC) 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSE----------PNVSMIITDYWMPEMTGYELLKKVKESSK 99
Cdd:cd17581     1 VLAVDDSLVDRKVIERLLRISSCRVTAVDSGKRALEFLGLEdeedssnfnePKVNMIITDYCMPGMTGYDLLKKVKESSA 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|..
gi 2445448931 100 LKKIPVVIMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRL 141
Cdd:cd17581    81 LKEIPVVIMSSENIPTRISRCLEEGAEDFLLKPVKLADVKRL 122

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 2445448931  27 PPHVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVV 106
Cdd:COG3706     1 PARILVVDDDPTNRKLLRRLLEAAGYEVVEAADGEEALELLQEHR-PDLILLDLEMPDMDGLELCRRLRADPRTADIPII 79

                          90       100       110
                  ....*....|....*....|....*....|....*....
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDvsrLFSRV 145
Cdd:COG3706    80 FLTALDDEEDRARALEAGADDYLTKPFDPEE---LLARV 115

phosphoacceptor receiver (REC) domain of type A Arabidopsis response regulators (ARRs) and similar proteins; Type-A response regulators of Arabidopsis (ARRs) are involved in cytokinin signaling, which involves a phosphorelay cascade by histidine kinase receptors (AHKs), histidine phosphotransfer proteins (AHPs) and downstream ARRs. Cytokinin is a plant hormone implicated in many growth and development processes including shoot organogenesis, leaf senescence, sink/source relationships, vascular development, lateral bud release, and photomorphogenic development. Type-A ARRs function downstream of and are regulated by type-B ARRs, which are a class of MYB-type transcription factors. As primary cytokinin response genes, type-A ARRs act as redundant negative feedback regulators of cytokinin signaling by inactivating the phosphorelay. ARRs are divided into two groups, type-A and -B, according to their sequence and domain structure. Type-A ARRs are similar in domain structure to CheY, in that they lack a typical output domain and only contain a stand-alone receiver (REC) 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSE----------PNVSMIITDYWMPEMTGYELLKKVKESSK 99
Cdd:cd17581     1 VLAVDDSLVDRKVIERLLRISSCRVTAVDSGKRALEFLGLEdeedssnfnePKVNMIITDYCMPGMTGYDLLKKVKESSA 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|..
gi 2445448931 100 LKKIPVVIMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRL 141
Cdd:cd17581    81 LKEIPVVIMSSENIPTRISRCLEEGAEDFLLKPVKLADVKRL 122

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 2445448931  27 PPHVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVV 106
Cdd:COG3706     1 PARILVVDDDPTNRKLLRRLLEAAGYEVVEAADGEEALELLQEHR-PDLILLDLEMPDMDGLELCRRLRADPRTADIPII 79

                          90       100       110
                  ....*....|....*....|....*....|....*....
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDvsrLFSRV 145
Cdd:COG3706    80 FLTALDDEEDRARALEAGADDYLTKPFDPEE---LLARV 115

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  27 PPHVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVV 106
Cdd:COG3437     6 APTVLIVDDDPENLELLRQLLRTLGYDVVTAESGEEALELLLEAP-PDLILLDVRMPGMDGFELLRLLRADPSTRDIPVI 84

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRLFSRVL 146
Cdd:COG3437    85 FLTALADPEDRERALEAGADDYLTKPFDPEELLARVRNAL 124

DNA-binding transcriptional response regulator, NtrC family, contains REC, AAA-type ATPase, and a Fis-type DNA-binding domains [Signal transduction mechanisms];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  27 PPHVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSklKKIPVV 106
Cdd:COG2204     2 MARILVVDDDPDIRRLLKELLERAGYEVETAASGEEALALLREEP-PDLVLLDLRMPGMDGLELLRELRALD--PDLPVI 78

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRLFSRVL 146
Cdd:COG2204    79 LLTGYGDVETAVEAIKAGAFDYLTKPFDLEELLAAVERAL 118

phosphoacceptor receiver (REC) domain of type B Arabidopsis response regulators (ARRs) and similar domains; Type-B ARRs (Arabidopsis response regulators) are a class of MYB-type transcription factors that act as major players in the transcriptional activation of cytokinin-responsive genes. They directly regulate the expression of type-A ARR genes and other downstream target genes. Cytokinin is a plant hormone implicated in many growth and development processes including shoot organogenesis, leaf senescence, sink/source relationships, vascular development, lateral bud release, and photomorphogenic development. Cytokinin signaling involves a phosphorelay cascade by histidine kinase receptors (AHKs), histidine phosphotransfer proteins (AHPs) and downstream ARRs. ARRs are divided into two groups, type-A and -B, according to their sequence and domain structure. Type-B ARRs contain a receiver (REC) domain and a large C-terminal extension that has characteristics of an effector or output domain, with a Myb-like DNA binding domain referred to as the GARP domain. The GARP domain is a motif specific to plant transcription factors. 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPN-VSMIITDYWMPEMTGYELLKKVKESsklKKIPVVIM 108
Cdd:cd17584     1 VLVVDDDPTCLAILKRMLLRCGYQVTTCTDAEEALSMLRENKDeFDLVITDVHMPDMDGFEFLELIRLE---MDLPVIMM 77

                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 2445448931 109 SSENVPTRISRCLEEGAEDFLVKPVRPSDVSRLFSRVL 146
Cdd:cd17584    78 SADGSTSTVMKGLAHGACDYLLKPVSIEDLKNIWQHVV 115

DNA-binding response regulator, OmpR family, contains REC and winged-helix (wHTH) domain [Signal transduction mechanisms, Transcription];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  27 PPHVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSklKKIPVV 106
Cdd:COG0745     1 MPRILVVEDDPDIRELLADALEREGYEVDTAADGEEALELLEEER-PDLILLDLMLPGMDGLEVCRRLRARP--SDIPII 77

                          90       100       110
                  ....*....|....*....|....*....|....*....
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDvsrLFSRV 145
Cdd:COG0745    78 MLTARDDEEDRVRGLEAGADDYLTKPFDPEE---LLARI 113

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLgSEPNVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVIMS 109
Cdd:cd17598     1 ILIVEDSPTQAEQLKHILEEQGYKVQVARNGREALAML-AEHRPTLVISDIVMPEMDGYELCRKIKSDPDLKDIPVILLT 79

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 2445448931 110 SENVPTRISRCLEEGAEDFLVKPVrpsDVSRLFSRV 145
Cdd:cd17598    80 TLSDPRDVIRGLECGADNFITKPY---DEKYLLSRI 112

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 2445448931  29 HVLAVDDSSVDRAVIAGILRSSRFRVT-AVDsGKRALELLGSEpNVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVI 107
Cdd:cd17562     2 KILAVDDSASIRQMVSFTLRGAGYEVVeAAD-GRDALSKAQSK-KFDLIITDQNMPNMDGIELIKELRKLPAYKFTPILM 79

                          90       100
                  ....*....|....*....|....*...
gi 2445448931 108 MSSENVPTRISRCLEEGAEDFLVKPVRP 135
Cdd:cd17562    80 LTTESSDEKKQEGKAAGATGWLVKPFDP 107

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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  29 HVLAVDDSSVDRAVIAGILRSSRF--RVTAVDSGKRALELL------GSEPNVSMIITDYWMPEMTGYELLKKVKESSKL 100
Cdd:cd17557     1 TILLVEDNPGDAELIQEAFKEAGVpnELHVVRDGEEALDFLrgegeyADAPRPDLILLDLNMPRMDGFEVLREIKADPDL 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*
gi 2445448931 101 KKIPVVIMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRLFSRV 145
Cdd:cd17557    81 RRIPVVVLTTSDAEEDIERAYELGANSYIVKPVDFEEFVEAIRSL 125

phosphoacceptor receiver (REC) domain of cyclic di-GMP phosphodiesterase response regulator RpfG and similar proteins; Cyclic di-GMP phosphodiesterase response regulator RpfG, together with sensory/regulatory protein RpfC, constitute a two-component system implicated in sensing and responding to the diffusible signal factor (DSF) that is essential for cell-cell signaling. RpfC is a hybrid sensor/histidine kinase that phosphorylates and activates RpfG, which degrades cyclic di-GMP to GMP, leading to the activation of Clp, a global transcriptional regulator that regulates a large set of genes in the DSF pathway. RpfG contains a CheY-like receiver domain attached to a histidine-aspartic acid-glycine-tyrosine-proline (HD-GYP) cyclic di-GMP phosphodiesterase 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 2445448931  28 PHVLAVDDSSVDRAVIAGILRS-SRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVV 106
Cdd:cd17551     1 MRILIVDDNPTNLLLLEALLRSaGYLEVVSFTDPREALAWCRENP-PDLILLDYMMPGMDGLEFIRRLRALPGLEDVPIV 79

                          90       100       110
                  ....*....|....*....|....*....|...
gi 2445448931 107 IMSSEN-VPTRIsRCLEEGAEDFLVKPVRPSDV 138
Cdd:cd17551    80 MITADTdREVRL-RALEAGATDFLTKPFDPVEL 111

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVIMS 109
Cdd:cd19920     1 ILIVDDVPDNLRLLSELLRAAGYRVLVATDGQQALQRAQAEP-PDLILLDVMMPGMDGFEVCRRLKADPATRHIPVIFLT 79

                          90       100
                  ....*....|....*....|....
gi 2445448931 110 SENVPTRISRCLEEGAEDFLVKPV 133
Cdd:cd19920    80 ALTDTEDKVKGFELGAVDYITKPF 103

DNA-binding response regulator DpiB of citrate/malate metabolism [Transcription, Signal transduction mechanisms];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  29 HVLAVDDSSVDRAVIAGILRSSRF--RVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKEssKLKKIPVV 106
Cdd:COG4565     5 RVLIVEDDPMVAELLRRYLERLPGfeVVGVASSGEEALALLAEHR-PDLILLDIYLPDGDGLELLRELRA--RGPDVDVI 81

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSRLFSRVL 146
Cdd:COG4565    82 VITAARDPETVREALRAGVVDYLIKPFTFERLREALERYL 121

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        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSE-PNVsmIITDYWMPEMTGYELLKKVKESSKLKKIPVVIM 108
Cdd:cd17580     1 ILVVDDNEDAAEMLALLLELEGAEVTTAHSGEEALEAAQRFrPDV--ILSDIGMPGMDGYELARRLRELPWLANTPAIAL 78

                          90       100       110
                  ....*....|....*....|....*....|...
gi 2445448931 109 SSENVPTRISRCLEEGAEDFLVKPVRPSDVSRL 141
Cdd:cd17580    79 TGYGQPEDRERALEAGFDAHLVKPVDPDELIEL 111

phosphoacceptor receiver (REC) domain of C4-dicarboxylic acid transport protein D (DctD) and similar proteins; C4-dicarboxylic acid transport protein D (DctD) is part of the two-component regulatory system DctB/DctD, which regulates C4-dicarboxylate transport via regulation of expression of the dctPQM operon and dctA. It is an activator of sigma(54)-RNA polymerase holoenzyme that uses the energy released from ATP hydrolysis to stimulate the isomerization of a closed promoter complex to an open complex capable of initiating transcription. DctD is a member of the NtrC family, characterized by a domain architecture containing an N-terminal REC domain, followed by a central sigma-54 interaction/ATPase domain, and a C-terminal DNA binding domain. The ability of the central domain to hydrolyze ATP and thus to interact effectively with a complex of RNA polymerase, sigma54, and promoter, is controlled by the phosphorylation status of the REC 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPNvSMIITDYWMPEMTGYELLKKVKESSklKKIPVVIMS 109
Cdd:cd17549     1 VLLVDDDADVREALQQTLELAGFRVRAFADAEEALAALSPDFP-GVVISDIRMPGMDGLELLAQIRELD--PDLPVILIT 77

                          90       100
                  ....*....|....*....|....*..
gi 2445448931 110 SE-NVPTRIsRCLEEGAEDFLVKPVRP 135
Cdd:cd17549    78 GHgDVPMAV-EAMRAGAYDFLEKPFDP 103

phosphoacceptor receiver (REC) domain of PhoB response regulator from the OmpR family; The transcription factor PhoB is a component of the PhoR/PhoB two-component system, a key regulatory protein network that facilitates response to inorganic phosphate (Pi) starvation conditions by turning on the phosphate (pho) regulon whose products are involved in phosphorus uptake and metabolism. PhoB is a member of the OmpR family of DNA-binding response regulators that contains REC and winged helix-turn-helix (wHTH) DNA-binding output effector 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 2445448931  28 PHVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLgSEPNVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVI 107
Cdd:cd17618     1 RTILIVEDEPAIREMIAFNLERAGFDVVEAEDAESAVNLI-VEPRPDLILLDWMLPGGSGIQFIRRLKRDEMTRDIPIIM 79

                          90       100
                  ....*....|....*....|....*...
gi 2445448931 108 MSSENVPTRISRCLEEGAEDFLVKPVRP 135
Cdd:cd17618    80 LTARGEEEDKVRGLEAGADDYITKPFSP 107

phosphoacceptor receiver (REC) domain of chemotaxis response regulator protein-glutamate methylesterase CheB and similar chemotaxis proteins; Methylesterase CheB is a chemotaxis response regulator with an N-terminal REC domain and a C-terminal methylesterase domain. Chemotaxis is a behavior known in motile bacteria that directs their movement in response to chemical gradients. CheB is a phosphorylation-activated response regulator involved in the reversible modification of bacterial chemotaxis receptors. It catalyzes the demethylation of specific methylglutamate residues introduced into the chemoreceptors (methyl-accepting chemotaxis proteins) by CheR. The CheB REC domain packs against the active site of the C-terminal domain and inhibits methylesterase activity by directly restricting access to the active site. Also included in this family is chemotaxis response regulator CheY, which contains a stand-alone REC domain, and an uncharacterized subfamily composed of proteins containing an N-terminal REC domain and a C-terminal CheY-P phosphatase (CheC) 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 2445448931  30 VLAVDDSSVDRAVIAGILRS-SRFRV--TAVDsGKRALELLGSE-PNVsmIITDYWMPEMTGYELLKKVKessKLKKIPV 105
Cdd:cd17541     3 VLIVDDSAVMRKLLSRILESdPDIEVvgTARD-GEEALEKIKELkPDV--ITLDIEMPVMDGLEALRRIM---AERPTPV 76

                          90       100       110
                  ....*....|....*....|....*....|....*
gi 2445448931 106 VIMSS---ENVPTRIsRCLEEGAEDFLVKPVRPSD 137
Cdd:cd17541    77 VMVSSlteEGAEITL-EALELGAVDFIAKPSGGIS 110

response regulator PleD; Reviewed

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVIMS 109
Cdd:PRK09581    5 ILVVDDIPANVKLLEAKLLAEYYTVLTASSGAEAIAICEREQ-PDIILLDVMMPGMDGFEVCRRLKSDPATTHIPVVMVT 83

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 2445448931 110 SENVPTRISRCLEEGAEDFLVKPVrpSDVSrLFSRV 145
Cdd:PRK09581   84 ALDDPEDRVRGLEAGADDFLTKPI--NDVA-LFARV 116

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAV-DSGKRALELLgSEPNVSMIITDYWMPEMTGYELLKKVkesSKLKKIPVVIM 108
Cdd:COG3707     6 VLVVDDEPLRRADLREGLREAGYEVVAEaADGEDAVELV-RELKPDLVIVDIDMPDRDGLEAARQI---SEERPAPVILL 81

                          90       100       110
                  ....*....|....*....|....*....|
gi 2445448931 109 SSENVPTRISRCLEEGAEDFLVKPVRPSDV 138
Cdd:COG3707    82 TAYSDPELIERALEAGVSAYLVKPLDPEDL 111

two component system sensor kinase;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  29 HVLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALElLGSEPNVSMIITDYWMPEMTGYELLKKVKESSKL--KKIPVV 106
Cdd:PRK15347  692 QILLVDDVETNRDIIGMMLVELGQQVTTAASGTEALE-LGRQHRFDLVLMDIRMPGLDGLETTQLWRDDPNNldPDCMIV 770

                          90       100       110
                  ....*....|....*....|....*....|....
gi 2445448931 107 IMSSENVPTRISRCLEEGAEDFLVKPVRPSDVSR 140
Cdd:PRK15347  771 ALTANAAPEEIHRCKKAGMNHYLTKPVTLAQLAR 804

chemotaxis protein CheY;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  31 LAVDDSSVDRAVIAGILRSSRFR-VTAVDSGKRALELLGSEpNVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVIMS 109
Cdd:PRK10610    9 LVVDDFSTMRRIVRNLLKELGFNnVEEAEDGVDALNKLQAG-GFGFVISDWNMPNMDGLELLKTIRADGAMSALPVLMVT 87

                          90       100       110
                  ....*....|....*....|....*....|....*..
gi 2445448931 110 SENVPTRISRCLEEGAEDFLVKPVRPSDVSRLFSRVL 146
Cdd:PRK10610   88 AEAKKENIIAAAQAGASGYVVKPFTAATLEEKLNKIF 124

phosphoacceptor receiver (REC) domain of plant ethylene receptors ETR1, ETR2, and EIN4, and similar proteins; Plant ethylene receptors contain N-terminal transmembrane domains that contain an ethylene binding site and also serve in localization of the receptor to the endoplasmic reticulum or the Golgi apparatus and a C-terminal histidine kinase (HK)-like domain. There are five ethylene receptors (ETR1, ERS1, ETR2, ERS2, and EIN4) in Arabidopsis thaliana. ETR1, ETR2, and EIN4 also contain REC domains C-terminal to the HK domain. ETR1 and ERS1 belong to subfamily 1, and have functional HK domains while ETR2, ERS2, and EIN4 belong to subfamily 2, and lack the necessary residues for HK activity and may function as serine/threonine kinases. The plant hormone ethylene plays an important role in plant growth and development. It regulates seed germination, seedling growth, leaf and petal abscission, fruit ripening, organ senescence, and pathogen responses. 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPN-VSMIITDYWMPEMTGYELLKKVKESSKLKKIP-VVI 107
Cdd:cd19933     3 VLLVDDNAVNRMVTKGLLEKLGCEVTTVSSGEECLNLLASAEHsFQLVLLDLCMPEMDGFEVALRIRKLFGRRERPlIVA 82

                          90       100
                  ....*....|....*....|....*.
gi 2445448931 108 MSSENVPTRISRCLEEGAEDFLVKPV 133
Cdd:cd19933    83 LTANTDDSTREKCLSLGMNGVITKPV 108

phosphoacceptor receiver (REC) domain of nitrogen regulatory protein C 1 (NtrC1) from Aquifex aeolicus and similar NtrC family response regulators; NtrC family proteins are transcriptional regulators that have REC, AAA+ ATPase/sigma-54 interaction, and DNA-binding output domains. This subfamily of NtrC proteins include Aquifex aeolicus NtrC1 and Vibrio quorum-sensing signal integrator LuxO. The N-terminal REC domain of NtrC proteins regulate the activity of the protein and its phosphorylation controls the AAA+ domain oligomerization, while the central AAA+ domain participates in nucleotide binding, hydrolysis, oligomerization, and sigma54 interaction. 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 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELL-GSEPNVsmIITDYWMPEMTGYELLKKVKESSklKKIPVVIM 108
Cdd:cd17572     1 VLLVEDSPSLAALYQEYLSDEGYKVTHVETGKEALAFLsDQPPDV--VLLDLKLPDMSGMEILKWIQERS--LPTSVIVI 76

                          90       100       110
                  ....*....|....*....|....*....|....*.
gi 2445448931 109 S---SENVPTRISRcleEGAEDFLVKPVrpsDVSRL 141
Cdd:cd17572    77 TahgSVDIAVEAMR---LGAYDFLEKPF---DADRL 106

DNA-binding response regulator, FixJ family, consists of REC and HTH domains [Signal transduction mechanisms, Transcription];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  34 DDSSVdRAVIAGILRSSRFRVTAVDSGKRALE-LLGSEPNVsmIITDYWMPEMTGYELLKKVKESSKLkkIPVVIMSSE- 111
Cdd:COG4566     7 DDEAV-RDSLAFLLESAGLRVETFASAEAFLAaLDPDRPGC--LLLDVRMPGMSGLELQEELAARGSP--LPVIFLTGHg 81

                          90       100
                  ....*....|....*....|....*.
gi 2445448931 112 NVPTrISRCLEEGAEDFLVKPVRPSD 137
Cdd:COG4566    82 DVPM-AVRAMKAGAVDFLEKPFDDQA 106

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPNVSMIITDYWMPEMTGYELLKKVKESSKLKKIPVVIMS 109
Cdd:cd18160     2 ILLADDEPSVRKFIVTTLKKAGYAVTEAESGAEALEKLQQGKDIDIVVTDIVMPEMDGIELAREARKIDPDVKILFISGG 81

                          90       100
                  ....*....|....*....|...
gi 2445448931 110 SENVPTRISRCLeeGAEDFLVKP 132
Cdd:cd18160    82 AAAAPELLSDAV--GDNATLKKP 102

phosphoacceptor receiver (REC) domain of CusR-like OmpR family response regulators; Escherichia coli CusR is part of the CusS/CusR two-component system (TCS) that is involved in response to copper and silver. Other members of this subfamily include Escherichia coli PcoR, Pseudomonas syringae CopR, and Streptomyces coelicolor CutR, which are all transcriptional regulatory proteins and components of TCSs that regulate genes involved in copper resistance and/or metabolism. member of the subfamily is Escherichia coli HprR (hydrogen peroxide response regulator), previously called YdeW, which is part of the HprSR (or YedVW) TCS involved in stress response to hydrogen peroxide, as well as Cupriavidus metallidurans CzcR, which is part of the CzcS/CzcR TCS involved in the control of cobalt, zinc, and cadmium homeostasis. Members of this subfamily belong to the OmpR family of DNA-binding response regulators, which 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2445448931  30 VLAVDDSSVDRAVIAGILRSSRFRVTAVDSGKRALELLGSEPnVSMIITDYWMPEMTGYELLKKVKESSKlkKIPVVIMS 109
Cdd:cd19935     1 ILVVEDEKKLAEYLKKGLTEEGYAVDVAYDGEDGLHLALTNE-YDLIILDVMLPGLDGLEVLRRLRAAGK--QTPVLMLT 77

                          90       100
                  ....*....|....*....|....
gi 2445448931 110 S-ENVPTRIsRCLEEGAEDFLVKP 132
Cdd:cd19935    78 ArDSVEDRV-KGLDLGADDYLVKP 100