phosphoacceptor receiver (REC) domain of FixJ family response regulators; FixJ family response regulators contain an N-terminal receiver domain (REC) and a C-terminal LuxR family helix-turn-helix (HTH) DNA-binding output domain. The Sinorhizobium meliloti two-component system FixL/FixJ regulates nitrogen fixation in response to oxygen during symbiosis. Under microaerobic conditions, the kinase FixL phosphorylates the response regulator FixJ resulting in the regulation of nitrogen fixation genes such as nifA and fixK. 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 1573292601  23 VSLVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASG 90
Cdd:cd17537     3 VYVVDDDEAVRDSLAFLLRSVGLAVKTFTSASAFLAAAPPDQPGCLVLDVRMPGMSGLELQDELLARG 70

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 1573292601  25 LVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASGWRGKALLLDGPGST 104
Cdd:pfam00072   3 IVDDDPLIRELLRQLLEKEGYVVAEADDGKEALELLKEERPDLILLDINMPGMDGLELLKRIRRRDPTTPVIILTAHGDE 82

                          90       100       110
                  ....*....|....*....|....*....|
gi 1573292601 105 gPTVLEAERYG-DKVLQRTVGDRTLLTAIA 133
Cdd:pfam00072  83 -DDAVEALEAGaDDFLSKPFDPDELLAAIR 111

phosphoacceptor receiver (REC) domain of FixJ family response regulators; FixJ family response regulators contain an N-terminal receiver domain (REC) and a C-terminal LuxR family helix-turn-helix (HTH) DNA-binding output domain. The Sinorhizobium meliloti two-component system FixL/FixJ regulates nitrogen fixation in response to oxygen during symbiosis. Under microaerobic conditions, the kinase FixL phosphorylates the response regulator FixJ resulting in the regulation of nitrogen fixation genes such as nifA and fixK. 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 1573292601  23 VSLVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASG 90
Cdd:cd17537     3 VYVVDDDEAVRDSLAFLLRSVGLAVKTFTSASAFLAAAPPDQPGCLVLDVRMPGMSGLELQDELLARG 70

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 1573292601  25 LVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASGWRGKALLLDGPGST 104
Cdd:COG2204     7 VVDDDPDIRRLLKELLERAGYEVETAASGEEALALLREEPPDLVLLDLRMPGMDGLELLRELRALDPDLPVILLTGYGDV 86

                          90
                  ....*....|.
gi 1573292601 105 gPTVLEAERYG 115
Cdd:COG2204    87 -ETAVEAIKAG 96

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1573292601  25 LVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASG 90
Cdd:cd00156     2 IVDDDPAIRELLKSLLEREGYEVDTAADGEEALELLREERPDLVLLDLMMPGMDGLELLRKLRELP 67

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1573292601  26 VDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRA 88
Cdd:cd17554     6 VDDEENIRELYKEELEDEGYEVVTAGNGEEALEKLESEDPDLVILDIKMPGMDGLETLRKIRE 68

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1573292601  25 LVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASG 90
Cdd:COG0745     6 VVEDDPDIRELLADALEREGYEVDTAADGEEALELLEEERPDLILLDLMLPGMDGLEVCRRLRARP 71

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1573292601  23 VSLVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADpQSRDYPCIIL-DLEMEDIGGLDLLRRMRA 88
Cdd:cd17549     1 VLLVDDDADVREALQQTLELAGFRVRAFADAEEALAA-LSPDFPGVVIsDIRMPGMDGLELLAQIRE 66

phosphoacceptor receiver (REC) domain of MtPhoP-like OmpR family response regulators; Mycobacterium tuberculosis PhoP (MtPhoP) is part of the PhoP/PhoR two-component system that is involved in phosphate control by stimulating expression of genes involved in scavenging, transport and mobilization of phosphate, and repressing the utilization of nitrogen sources. Also included in this subfamily is Mycobacterium tuberculosis transcriptional regulatory protein TcrX, part of the two-component regulatory system TcrY/TcrX that may be involved in virulence. Members of this subfamily belong to the OmpR family of DNA-binding response regulators, which are characterized by a REC domain and a winged helix-turn-helix (wHTH) DNA-binding 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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1573292601  23 VSLVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASGWRGKALLL 98
Cdd:cd17615     2 VLVVDDEPNITELLSMALRYEGWDVETAADGAEALAAAREFRPDAVVLDIMLPDMDGLEVLRRLRADGPDVPVLFL 77

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1573292601  25 LVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRA 88
Cdd:COG3706     6 VVDDDPTNRKLLRRLLEAAGYEVVEAADGEEALELLQEHRPDLILLDLEMPDMDGLELCRRLRA 69

phosphoacceptor receiver (REC) domain of ChvI-like OmpR family response regulators; Sinorhizobium meliloti ChvI is part of the ExoS/ChvI two-component regulatory system (TCS) that is required for nitrogen-fixing symbiosis and exopolysaccharide synthesis. ExoS/ChvI also play important roles in regulating biofilm formation, motility, nutrient utilization, and the viability of free-living bacteria. ChvI 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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1573292601  23 VSLVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRA 88
Cdd:cd19936     1 IALVDDDRNILTSVSMALEAEGFSVETYTDGASALDGLNARPPDLAILDIKMPRMDGMELLQRLRQ 66

two-component system response regulator PmrA;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1573292601  37 QLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASGWRGKALLL 98
Cdd:PRK10643   17 ILALQTEGYACDCASTAREAEALLESGHYSLVVLDLGLPDEDGLHLLRRWRQKKYTLPVLIL 78

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1573292601  40 LRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRAS 89
Cdd:cd17623    18 LEMEGFNVRAAHDGEQGLAALLEGSPDLVVLDVMLPKMNGLDVLKELRKT 67

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 1573292601  23 VSLVDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRASGWRGKALLLDGPG 102
Cdd:cd17572     1 VLLVEDSPSLAALYQEYLSDEGYKVTHVETGKEALAFLSDQPPDVVLLDLKLPDMSGMEILKWIQERSLPTSVIVITAHG 80

                          90
                  ....*....|...
gi 1573292601 103 STGPTVlEAERYG 115
Cdd:cd17572    81 SVDIAV-EAMRLG 92

phosphoacceptor receiver (REC) domain of BsPhoP-like OmpR family response regulators; Bacillus subtilis PhoP (BsPhoP) is part of the PhoPR two-component system that participates in a signal transduction network that controls adaptation of the bacteria to phosphate deficiency by regulating (activating or repressing) genes of the Pho regulon upon phosphorylation by PhoR. When activated, PhoPR directs expression of phosphate scavenging enzymes, lowers synthesis of the phosphate-rich wall teichoic acid (WTA) and initiates synthesis of teichuronic acid, a non-phosphate containing replacement anionic polymer. Members of this subfamily belong to the OmpR family of DNA-binding response regulators, which are characterized by a REC domain and a winged helix-turn-helix (wHTH) DNA-binding 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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1573292601  26 VDGEPTARRARQLMLRSEGFAVRSYPTCAAILADPQSRDYPCIILDLEMEDIGGLDLLRRMRAS 89
Cdd:cd19937     3 VDDEEDIVELLKYNLEKEGYEVVTAYDGEEALKRAKDEKPDLIILDLMLPGIDGLEVCRILRSD 66