phosphoacceptor receiver (REC) domain of hybrid sensor histidine kinases/response regulators similar to Arabidopsis thaliana CKI1 and Escherichia coli RcsC; This family is composed of hybrid sensor histidine kinases/response regulators that are sensor histidine kinases (HKs) fused with a REC domain, similar to the sensor histidine kinase CKI1 from Arabidopsis thaliana, which is involved in multi-step phosphorelay (MSP) signaling that mediates responses to a variety of important stimuli in plants. MSP involves a signal being transferred from HKs via histidine phosphotransfer proteins (AHP1-AHP5) to nuclear response regulators. The CKI1 REC domain specifically interacts with the downstream signaling protein AHP2, AHP3 and AHP5. The plant MSP system has evolved from the prokaryotic two-component system (TCS), which allows organisms to sense and respond to changes in environmental conditions. This family also includes bacterial hybrid sensor HKs such as Escherichia coli RcsC, which is a component of the Rcs signalling pathway that controls a variety of physiological functions like capsule synthesis, cell division, and motility. 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQYNK-- 87
Cdd:cd17546   1 VLVVDDNPVNRKVLKKLLEKLGY-EVDVAENGQEALELLKE-----EPFDLVLMDLQMPVMDGLEATRRIRELEGGGRrt 74

                        90       100       110
                ....*....|....*....|....*....|....*....
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVL 126
Cdd:cd17546  75 PIIALTANALEEDREKCLEAGMDDYLSKPVKLDQLKEVL 113

phosphoacceptor receiver (REC) domain of hybrid sensor histidine kinases/response regulators similar to Arabidopsis thaliana CKI1 and Escherichia coli RcsC; This family is composed of hybrid sensor histidine kinases/response regulators that are sensor histidine kinases (HKs) fused with a REC domain, similar to the sensor histidine kinase CKI1 from Arabidopsis thaliana, which is involved in multi-step phosphorelay (MSP) signaling that mediates responses to a variety of important stimuli in plants. MSP involves a signal being transferred from HKs via histidine phosphotransfer proteins (AHP1-AHP5) to nuclear response regulators. The CKI1 REC domain specifically interacts with the downstream signaling protein AHP2, AHP3 and AHP5. The plant MSP system has evolved from the prokaryotic two-component system (TCS), which allows organisms to sense and respond to changes in environmental conditions. This family also includes bacterial hybrid sensor HKs such as Escherichia coli RcsC, which is a component of the Rcs signalling pathway that controls a variety of physiological functions like capsule synthesis, cell division, and motility. 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQYNK-- 87
Cdd:cd17546   1 VLVVDDNPVNRKVLKKLLEKLGY-EVDVAENGQEALELLKE-----EPFDLVLMDLQMPVMDGLEATRRIRELEGGGRrt 74

                        90       100       110
                ....*....|....*....|....*....|....*....
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVL 126
Cdd:cd17546  75 PIIALTANALEEDREKCLEAGMDDYLSKPVKLDQLKEVL 113

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D         10 VLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKnLQYNKPI 89
Cdd:pfam00072   1 VLIVDDDPLIRELLRQLLEKEGY-VVAEADDGKEALELLKE-----ERPDLILLDINMPGMDGLELLKRIRR-RDPTTPV 73

                          90       100       110
                  ....*....|....*....|....*....|....*..
8PHX_D         90 IALTAFADESNVKECLNSGMSGFITKPISKTNIKKVL 126
Cdd:pfam00072  74 IILTAHGDEDDAVEALEAGADDFLSKPFDPDELLAAI 110

cheY-homologous receiver domain; CheY regulates the clockwise rotation of E. coli flagellar motors. This domain contains a phosphoacceptor site that is phosphorylated by histidine kinase homologues.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|.
8PHX_D           8 LRVLVAEDNLVNQEVISRMLKQEGITNLTMAcNGAKAIDFVKEsiennENFDLIFMDVQMP 68
Cdd:smart00448   1 MRILVVDDDPLLRELLKALLEKEGYEVDEAT-DGEEALELLKE-----EKPDLILLDIMMP 55

phosphoacceptor receiver (REC) domain of hybrid sensor histidine kinases/response regulators similar to Arabidopsis thaliana CKI1 and Escherichia coli RcsC; This family is composed of hybrid sensor histidine kinases/response regulators that are sensor histidine kinases (HKs) fused with a REC domain, similar to the sensor histidine kinase CKI1 from Arabidopsis thaliana, which is involved in multi-step phosphorelay (MSP) signaling that mediates responses to a variety of important stimuli in plants. MSP involves a signal being transferred from HKs via histidine phosphotransfer proteins (AHP1-AHP5) to nuclear response regulators. The CKI1 REC domain specifically interacts with the downstream signaling protein AHP2, AHP3 and AHP5. The plant MSP system has evolved from the prokaryotic two-component system (TCS), which allows organisms to sense and respond to changes in environmental conditions. This family also includes bacterial hybrid sensor HKs such as Escherichia coli RcsC, which is a component of the Rcs signalling pathway that controls a variety of physiological functions like capsule synthesis, cell division, and motility. 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQYNK-- 87
Cdd:cd17546   1 VLVVDDNPVNRKVLKKLLEKLGY-EVDVAENGQEALELLKE-----EPFDLVLMDLQMPVMDGLEATRRIRELEGGGRrt 74

                        90       100       110
                ....*....|....*....|....*....|....*....
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVL 126
Cdd:cd17546  75 PIIALTANALEEDREKCLEAGMDDYLSKPVKLDQLKEVL 113

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        7 HLRVLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQYN 86
Cdd:COG3706   1 PARILVVDDDPTNRKLLRRLLEAAGY-EVVEAADGEEALELLQE-----HRPDLILLDLEMPDMDGLELCRRLRADPRTA 74

                        90       100       110
                ....*....|....*....|....*....|....*
8PHX_D       87 K-PIIALTAFADESNVKECLNSGMSGFITKPISKT 120
Cdd:COG3706  75 DiPIIFLTALDDEEDRARALEAGADDYLTKPFDPE 109

hybrid sensory histidine kinase BarA; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D         8 LRVLVAEDNLVNQEVISRMLKqEGITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKN-LQYN 86
Cdd:PRK11107 668 LTVMAVDDNPANLKLIGALLE-EQVEHVVLCDSGHQAVEQAKQ-----RPFDLILMDIQMPGMDGIRACELIRQLpHNQN 741

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*.
8PHX_D        87 KPIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVLVEFLSN 132
Cdd:PRK11107 742 TPIIAVTAHAMAGERERLLSAGMDDYLAKPIDEAMLKQVLLRYKPG 787

phosphoacceptor receiver (REC) domain of DivK and similar proteins; Caulobacter crescentus DivK is an essential response regulator that is involved in the complex phosphorelay pathways controlling both cell division and motility. It localizes cell cycle regulators to specific poles of the cell during division. DivK contains a stand-alone 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        9 RVLVAEDNLVNQEVISRMLKQEGITNLTmACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQY-NK 87
Cdd:cd17548   1 KILIVEDNPLNMKLARDLLESAGYEVLE-AADGEEALEIARK-----EKPDLILMDIQLPGMDGLEATRLLKEDPATrDI 74

                        90       100       110
                ....*....|....*....|....*....|....
8PHX_D       88 PIIALTAFA---DESNVkecLNSGMSGFITKPIS 118
Cdd:cd17548  75 PVIALTAYAmkgDREKI---LEAGCDGYISKPID 105

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       11 LVAEDNLVNQEVISRMLKQEGITnLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQyNKPII 90
Cdd:cd00156   1 LIVDDDPAIRELLKSLLEREGYE-VDTAADGEEALELLRE-----ERPDLVLLDLMMPGMDGLELLRKLRELPP-DIPVI 73

                        90       100
                ....*....|....*....|....*.
8PHX_D       91 ALTAFADESNVKECLNSGMSGFITKP 116
Cdd:cd00156  74 VLTAKADEEDAVRALELGADDYLVKP 99

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        8 LRVLVAEDNLVNQEVISRMLKQ-EGITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNlQYN 86
Cdd:COG4565   4 IRVLIVEDDPMVAELLRRYLERlPGFEVVGVASSGEEALALLAE-----HRPDLILLDIYLPDGDGLELLRELRAR-GPD 77

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*
8PHX_D       87 KPIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVLVEFLS 131
Cdd:COG4565  78 VDVIVITAARDPETVREALRAGVVDYLIKPFTFERLREALERYLE 122

two component system sensor kinase;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D         8 LRVLVAEDNLVNQEVISRMLKQEGiTNLTMACNGAKAIDFVKESIennenFDLIFMDVQMPEVDGLKATKMIR---KNLQ 84
Cdd:PRK15347 691 LQILLVDDVETNRDIIGMMLVELG-QQVTTAASGTEALELGRQHR-----FDLVLMDIRMPGLDGLETTQLWRddpNNLD 764

                         90       100       110
                 ....*....|....*....|....*....|....
8PHX_D        85 YNKPIIALTAFADESNVKECLNSGMSGFITKPIS 118
Cdd:PRK15347 765 PDCMIVALTANAAPEEIHRCKKAGMNHYLTKPVT 798

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        8 LRVLVAEDNLVNQEVISRMLKQEGiTNLTMACNGAKAIDFVKESienNENFDLIFMDVQMPEVDGLKATKMIRKNLQYNK 87
Cdd:cd19933   1 LKVLLVDDNAVNRMVTKGLLEKLG-CEVTTVSSGEECLNLLASA---EHSFQLVLLDLCMPEMDGFEVALRIRKLFGRRE 76

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
8PHX_D       88 P--IIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVL 126
Cdd:cd19933  77 RplIVALTANTDDSTREKCLSLGMNGVITKPVSLHALGDEL 117

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        9 RVLVAEDNLVNQEVISRMLKQEGITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMP-EVDGLKATKMIRKNlqYNK 87
Cdd:cd17534   2 KILIVEDEAIIALDLKEILESLGYEVVGIADSGEEAIELAEE-----NKPDLILMDINLKgDMDGIEAAREIREK--FDI 74

                        90       100       110
                ....*....|....*....|....*....|....*.
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIK 123
Cdd:cd17534  75 PVIFLTAYSDEETLERAKETNPYGYLVKPFNERELK 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRML-KQEGITNLTMACNGAKAIDFVKESIennenFDLIFMDVQMPEVDGLKATKMIRKnLQYNKP 88
Cdd:cd17535   1 VLIVDDHPLVREGLRRLLeSEPDIEVVGEAADGEEALALLRELR-----PDVVLMDLSMPGMDGIEALRRLRR-RYPDLK 74

                        90       100       110
                ....*....|....*....|....*....|....
8PHX_D       89 IIALTAFADESNVKECLNSGMSGFITKPISKTNI 122
Cdd:cd17535  75 VIVLTAHDDPEYVLRALKAGAAGYLLKDSSPEEL 108

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        8 LRVLVAEDNLVNQEVISRMLKQEGITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQYNK 87
Cdd:cd19923   1 MKVLVVDDFSTMRRIIKNLLKELGFNNVEEAEDGVDALEKLKA-----GGFDFVITDWNMPNMDGLELLKTIRADGALSH 75

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....
8PHX_D       88 -PIIALTAFADESNVKECLNSGMSGFITKPIS----KTNIKKVL 126
Cdd:cd19923  76 lPVLMVTAEAKKENVIAAAQAGVNNYIVKPFTaatlKEKLEKIF 119

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        9 RVLVAEDNLVNQEVISRMLKQEGITN-LTMACNGAKAIDFV--KESIENNENFDLIFMDVQMPEVDGLKATKMIRKNLQY 85
Cdd:cd17557   1 TILLVEDNPGDAELIQEAFKEAGVPNeLHVVRDGEEALDFLrgEGEYADAPRPDLILLDLNMPRMDGFEVLREIKADPDL 80

                        90       100       110
                ....*....|....*....|....*....|....
8PHX_D       86 NK-PIIALTAFADESNVKECLNSGMSGFITKPIS 118
Cdd:cd17557  81 RRiPVVVLTTSDAEEDIERAYELGANSYIVKPVD 114

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        9 RVLVAEDNLVNQEVISRMLKQE-GITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKnlQYNK 87
Cdd:cd17541   2 RVLIVDDSAVMRKLLSRILESDpDIEVVGTARDGEEALEKIKE-----LKPDVITLDIEMPVMDGLEALRRIMA--ERPT 74

                        90       100       110
                ....*....|....*....|....*....|.
8PHX_D       88 PIIALTAFADE--SNVKECLNSGMSGFITKP 116
Cdd:cd17541  75 PVVMVSSLTEEgaEITLEALELGAVDFIAKP 105

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQE--GITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKnLQYNK 87
Cdd:cd17536   1 VLIVDDEPLIREGLKKLIDWEelGFEVVGEAENGEEALELIEE-----HKPDIVITDIRMPGMDGLELIEKIRE-LYPDI 74

                        90       100       110
                ....*....|....*....|....*....|....*....
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVL 126
Cdd:cd17536  75 KIIILSGYDDFEYAQKAIRLGVVDYLLKPVDEEELEEAL 113

phosphoacceptor receiver (REC) domain of DrrD-like OmpR family response regulators; DrrD is a OmpR/PhoB homolog from Thermotoga maritima whose function is not yet known. This subfamily also includes Streptococcus agalactiae transcriptional regulatory protein DltR, part of the DltS/DltR two-component system (TCS), and Pseudomonas aeruginosa transcriptional activator protein PfeR, part of the PfeR/PfeS TCS, which activates expression of the ferric enterobactin receptor. The DltS/DltR TCS regulates the expression of the dlt operon, which comprises four genes (dltA, dltB, dltC, and dltD) that catalyze the incorporation of D-alanine residues into the lipoteichoic acids. Members of this subfamily belong to the OmpR/PhoB family, which comprises of two domains, an N-terminal receiver domain and a C-terminal DNA-binding winged helix-turn-helix 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       11 LVAEDNLVNQEVISRMLKQEGITnLTMACNGAKAIDFVKesienNENFDLIFMDVQMPEVDGLKATKMIRKNlQYNKPII 90
Cdd:cd17625   1 LVVEDEKDLSEAITKHLKKEGYT-VDVCFDGEEGLEYAL-----SGIYDLIILDIMLPGMDGLEVLKSLREE-GIETPVL 73

                        90       100
                ....*....|....*....|....*...
8PHX_D       91 ALTAFADESNVKECLNSGMSGFITKPIS 118
Cdd:cd17625  74 LLTALDAVEDRVKGLDLGADDYLPKPFS 101

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKEsieNNENFDLIFMDVQMPEVDGLKATKMIRknLQYNKPI 89
Cdd:cd17584   1 VLVVDDDPTCLAILKRMLLRCGY-QVTTCTDAEEALSMLRE---NKDEFDLVITDVHMPDMDGFEFLELIR--LEMDLPV 74

                        90       100       110
                ....*....|....*....|....*....|....
8PHX_D       90 IALTAFADESNVKECLNSGMSGFITKPISKTNIK 123
Cdd:cd17584  75 IMMSADGSTSTVMKGLAHGACDYLLKPVSIEDLK 108

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        9 RVLVAEDNLVNQEVISRMLKQEGITnLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNLQY-NK 87
Cdd:cd17562   2 KILAVDDSASIRQMVSFTLRGAGYE-VVEAADGRDALSKAQS-----KKFDLIITDQNMPNMDGIELIKELRKLPAYkFT 75

                        90       100       110       120
                ....*....|....*....|....*....|....*....|...
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTN----IKKVL 126
Cdd:cd17562  76 PILMLTTESSDEKKQEGKAAGATGWLVKPFDPEQllevVKKVL 118

acetoacetate metabolism transcriptional regulator AtoC;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D         9 RVLVAEDNLVNQEVISRMLKQEGITNLTmACNGAKAIDFVKESienneNFDLIFMDVQMPEVDGLKATKMIRKnLQYNKP 88
Cdd:PRK11361   6 RILIVDDEDNVRRMLSTAFALQGFETHC-ANNGRTALHLFADI-----HPDVVLMDIRMPEMDGIKALKEMRS-HETRTP 78

                         90       100
                 ....*....|....*....|....*...
8PHX_D        89 IIALTAFADESNVKECLNSGMSGFITKP 116
Cdd:PRK11361  79 VILMTAYAEVETAVEALRCGAFDYVIKP 106

sigma-54-dependent response regulator transcription factor ZraR;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D         8 LRVLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKESIennenFDLIFMDVQMPEVDGLKATKMIrKNLQYNK 87
Cdd:PRK10365   6 IDILVVDDDISHCTILQALLRGWGY-NVALANSGRQALEQVREQV-----FDLVLCDVRMAEMDGIATLKEI-KALNPAI 78

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*
8PHX_D        88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVLVEFLSN 132
Cdd:PRK10365  79 PVLIMTAYSSVETAVEALKTGALDYLIKPLDFDNLQATLEKALAH 123

two-component system sensor histidine kinase RcsC;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D         8 LRVLVAEDNLVNQEVISRMLKQEGItNLTMACNGAKAIDFVKesienNENFDLIFMDVQMPEVDGLKATKMIRkNLQYNK 87
Cdd:PRK10841 802 MMILVVDDHPINRRLLADQLGSLGY-QCKTANDGVDALNVLS-----KNHIDIVLTDVNMPNMDGYRLTQRLR-QLGLTL 874

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|..
8PHX_D        88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVLVEF 129
Cdd:PRK10841 875 PVIGVTANALAEEKQRCLEAGMDSCLSKPVTLDVLKQTLTVY 916

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQEGITnLTMACNGAKAIDFVKESIEnnenfDLIFMDVQMPEVDGLKATKMIRKNLQY-NKP 88
Cdd:cd17598   1 ILIVEDSPTQAEQLKHILEEQGYK-VQVARNGREALAMLAEHRP-----TLVISDIVMPEMDGYELCRKIKSDPDLkDIP 74

                        90       100       110       120
                ....*....|....*....|....*....|....*....|...
8PHX_D       89 IIALTAFADESNVKECLNSGMSGFITKPISK----TNIKKVLV 127
Cdd:cd17598  75 VILLTTLSDPRDVIRGLECGADNFITKPYDEkyllSRIKYILV 117

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        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        8 LRVLVAEDNLVNQEVISRMLKQ-EGITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNlQYN 86
Cdd:cd19925   1 INVLIVEDDPMVAEIHRAYVEQvPGFTVIGTAGTGEEALKLLKE-----RQPDLILLDIYLPDGNGLDLLRELRAA-GHD 74

                        90       100       110       120
                ....*....|....*....|....*....|....*....|...
8PHX_D       87 KPIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVLVEF 129
Cdd:cd19925  75 VDVIVVTAANDVETVREALRLGVVDYLIKPFTFERLRQRLERY 117

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D        8 LRVLVAEDNLVNQEVISRMLKQEGITNLTMACNGAKAIDFVKEsiennENFDLIFMDVQMPEVDGLKATKMIRKNlQYNK 87
Cdd:cd17593   1 MKVLICDDSSMARKQLARALPADWDVEITFAENGEEALEILRE-----GRIDVLFLDLTMPVMDGYEVLEALPVE-QLET 74

                        90       100       110       120
                ....*....|....*....|....*....|....*....|..
8PHX_D       88 PIIALTAFADESNVKECLNSGMSGFITKPISKTNIKKVLVEF 129
Cdd:cd17593  75 KVIVVSGDVQPEAKERVLELGALAFLKKPFDPEKLAQLLEEL 116

phosphoacceptor receiver (REC) domain of probable transcriptional regulator Ycf29; Ycf29 is a probable response regulator of a two-component system (TCS), typically consisting a sensor and a response regulator, that functions in adaptation to changing environments. Processes regulated by TCSs in bacteria include sporulation, pathogenicity, virulence, chemotaxis, and membrane transport. Ycf29 contains an N-terminal REC domain and a LuxR-type helix-turn-helix DNA-binding output domain. 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
8PHX_D       10 VLVAEDNLVNQEVISRMLKQEGITNLTmACNGAKAIDFVkesieNNENFDLIFMDVQMPEVDGLKATKMIRKNLQYNK-P 88
Cdd:cd19927   1 ILLVDDDPGIRLAVKDYLEDQGFTVIA-ASNGLEALDLL-----NQYIPDLIISDIIMPGVDGYSLLGKLRKNADFDTiP 74

                        90       100
                ....*....|....*....|....*...
8PHX_D       89 IIALTAFADESNVKECLNSGMSGFITKP 116
Cdd:cd19927  75 VIFLTAKGMTSDRIKGYNAGCDGYLSKP 102