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
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 9230795      4 ILVIDDHPAVMEGTKTILEtDSNLSVDclSPEPSEQFIKQHDFSSYDLILMDLNLGG 60
Cdd:pfam00072   1 VLIVDDDPLIRELLRQLLE-KEGYVVA--EADDGKEALELLKEERPDLILLDINMPG 54

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
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 9230795      4 ILVIDDHPAVMEGTKTILEtDSNLSVDclSPEPSEQFIKQHDFSSYDLILMDLNLGG 60
Cdd:pfam00072   1 VLIVDDDPLIRELLRQLLE-KEGYVVA--EADDGKEALELLKEERPDLILLDINMPG 54

DNA-binding response regulator, NarL/FixJ family, contains REC and HTH domains [Signal transduction mechanisms, Transcription];

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 9230795    1 MKKILVIDDHPAVMEGTKTILETDSNLSV--DCLSPEPSEQFIKQHDFssyDLILMDLNLGG 60
Cdd:COG2197   1 MIRVLIVDDHPLVREGLRALLEAEPDIEVvgEAADGEEALELLEELRP---DVVLLDIRMPG 59

transcriptional regulator NarL; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 9230795     4 ILVIDDHPAVMEGTKTILETDSNLSV--DCLSPEPSEQFIKQHDfssYDLILMDLNLGGeVNG 64
Cdd:PRK10651   9 ILLIDDHPMLRTGVKQLISMAPDITVvgEASNGEQGIELAESLD---PDLILLDLNMPG-MNG 67

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
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 9230795      4 ILVIDDHPAVMEGTKTILEtDSNLSVDclSPEPSEQFIKQHDFSSYDLILMDLNLGG 60
Cdd:pfam00072   1 VLIVDDDPLIRELLRQLLE-KEGYVVA--EADDGKEALELLKEERPDLILLDINMPG 54

DNA-binding response regulator, NarL/FixJ family, contains REC and HTH domains [Signal transduction mechanisms, Transcription];

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 9230795    1 MKKILVIDDHPAVMEGTKTILETDSNLSV--DCLSPEPSEQFIKQHDFssyDLILMDLNLGG 60
Cdd:COG2197   1 MIRVLIVDDHPLVREGLRALLEAEPDIEVvgEAADGEEALELLEELRP---DVVLLDIRMPG 59

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
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 9230795    1 MKKILVIDDHPAVMEGTKTILEtDSNLSVDC-LSPEPSEQFIKQHDFssyDLILMDLNLGGE 61
Cdd:COG2204   2 MARILVVDDDPDIRRLLKELLE-RAGYEVETaASGEEALALLREEPP---DLVLLDLRMPGM 59

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 9230795    1 MKKILVIDDHPAVMEGTKTILETDSNLSVDCLSPEPSEQFIKQHDFssyDLILMDLNLGG 60
Cdd:COG3437   6 APTVLIVDDDPENLELLRQLLRTLGYDVVTAESGEEALELLLEAPP---DLILLDVRMPG 62

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 9230795    1 MKKILVIDDHPAVMEGTKTILEtDSNLSVDCLspEPSEQFIKQHDFSSYDLILMDLNLGG 60
Cdd:COG0745   1 MPRILVVEDDPDIRELLADALE-REGYEVDTA--ADGEEALELLEEERPDLILLDLMLPG 57

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 9230795    1 MKKILVIDDHPAVMEGTKTILETDSNLSVD--CLSPEPSEQFIKQHDFssyDLILMDLNLGGE 61
Cdd:COG4565   3 MIRVLIVEDDPMVAELLRRYLERLPGFEVVgvASSGEEALALLAEHRP---DLILLDIYLPDG 62

response regulator; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 9230795     1 MKKILVIDDHPAVMEGTKTILETDSNLSV--DCLSPEPSEQFIKQHdfsSYDLILMDLNLGG 60
Cdd:PRK09483   1 MINVLLVDDHELVRAGIRRILEDIKGIKVvgEACCGEDAVKWCRTN---AVDVVLMDMNMPG 59

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
               ....*....|....*....|....*....|....*....|....*....|....*.
gi 9230795   5 LVIDDHPAVMEGTKTILEtdsNLSVDCLSPEPSEQFIKQHDFSSYDLILMDLNLGG 60
Cdd:cd00156  1 LIVDDDPAIRELLKSLLE---REGYEVDTAADGEEALELLREERPDLVLLDLMMPG 53

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 9230795    2 KKILVIDDHPAVMEGTKTILEtDSNLSVD--CLSPEPSEQFIKQHDFssyDLILMDLNLGGEVNG 64
Cdd:cd17534   1 KKILIVEDEAIIALDLKEILE-SLGYEVVgiADSGEEAIELAEENKP---DLILMDINLKGDMDG 61