chemotaxis protein CheC, Class I; This subfamily contains Class I CheC proteins with phosphatase activity. The Class I cheC genes are generally found in firmicute and archaeal chemotaxis operons with cheD, usually translationally coupled. Class I CheCs interact with the CheD protein which is responsible for deamidation of certain glutamine residues to glutamates on the chemotaxis receptor proteins. This family contains two active sites with the consensus sequence ([DS]xxxExxNx(22)P), with four conserved residues thought to form the phosphatase active site. The C-terminal helix of CheC acts as a mimic of the natural enzymatic target of CheD, the alpha-helical receptors, and serves as the binding site for CheD. The CheC/CheD heterodimerization increases CheY-P phosphatase activity five-fold. Class I CheCs are involved in adaptation of the chemotaxis system.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  21 HIDALREIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGPENKVVCILLDMKGDINGMFMFLLDESITQL 100
Cdd:cd17909     1 QLDALKEIGNIGAGNAATALSQLLGKKVDMSVPEVKILPFEEVPELLGGPEEVVAGVLLRIEGDISGSILFIFPEESALK 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806 101 MLSSLFNKEESTLDEIEAIEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDICIDMVGAVLNVPMIRFSDVGDKVLFI 180
Cdd:cd17909    81 LVDLLLGREPGSTEELDEMELSALKEIGNILAGSYLNALSDFLGLTLLPSVPSLAVDMAGAILSSVLIELGQESDEALLI 160

                         170       180
                  ....*....|....*....|....*...
gi 2570605806 181 ENKFKMSDNYFTSHILMIPEMSSLREIL 208
Cdd:cd17909   161 ETEFSIEEEKIEGHFLLLPDPESLEKLL 188

chemotaxis protein CheC, Class I; This subfamily contains Class I CheC proteins with phosphatase activity. The Class I cheC genes are generally found in firmicute and archaeal chemotaxis operons with cheD, usually translationally coupled. Class I CheCs interact with the CheD protein which is responsible for deamidation of certain glutamine residues to glutamates on the chemotaxis receptor proteins. This family contains two active sites with the consensus sequence ([DS]xxxExxNx(22)P), with four conserved residues thought to form the phosphatase active site. The C-terminal helix of CheC acts as a mimic of the natural enzymatic target of CheD, the alpha-helical receptors, and serves as the binding site for CheD. The CheC/CheD heterodimerization increases CheY-P phosphatase activity five-fold. Class I CheCs are involved in adaptation of the chemotaxis system.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  21 HIDALREIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGPENKVVCILLDMKGDINGMFMFLLDESITQL 100
Cdd:cd17909     1 QLDALKEIGNIGAGNAATALSQLLGKKVDMSVPEVKILPFEEVPELLGGPEEVVAGVLLRIEGDISGSILFIFPEESALK 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806 101 MLSSLFNKEESTLDEIEAIEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDICIDMVGAVLNVPMIRFSDVGDKVLFI 180
Cdd:cd17909    81 LVDLLLGREPGSTEELDEMELSALKEIGNILAGSYLNALSDFLGLTLLPSVPSLAVDMAGAILSSVLIELGQESDEALLI 160

                         170       180
                  ....*....|....*....|....*...
gi 2570605806 181 ENKFKMSDNYFTSHILMIPEMSSLREIL 208
Cdd:cd17909   161 ETEFSIEEEKIEGHFLLLPDPESLEKLL 188

flagellar motor switch protein; Validated

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  16 ELDDVHIDALREIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGPEnkvVCILLDMKGDINGMFMFLLDE 95
Cdd:PRK08119   34 ELTDLEKDALGEIGNISMGSAATALSTLLNQKVNITTPVVSVTTLEELKKEFPIPY---VAVEVKYTEGLSGENLLVIKQ 110

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 2570605806  96 S----ITQLMLSSLFNKEESTLDEIEaieISAIKEIGNIMASSYVNAIASMLNMTISVSIPDI 154
Cdd:PRK08119  111 DdaaiIADLMMGGDGTVEEPELSEIE---LSAVQEAMNQMIGSAATSMSTMFNRKVDISPPKS 170

chemotaxis protein CheC, Class I; This subfamily contains Class I CheC proteins with phosphatase activity. The Class I cheC genes are generally found in firmicute and archaeal chemotaxis operons with cheD, usually translationally coupled. Class I CheCs interact with the CheD protein which is responsible for deamidation of certain glutamine residues to glutamates on the chemotaxis receptor proteins. This family contains two active sites with the consensus sequence ([DS]xxxExxNx(22)P), with four conserved residues thought to form the phosphatase active site. The C-terminal helix of CheC acts as a mimic of the natural enzymatic target of CheD, the alpha-helical receptors, and serves as the binding site for CheD. The CheC/CheD heterodimerization increases CheY-P phosphatase activity five-fold. Class I CheCs are involved in adaptation of the chemotaxis system.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  21 HIDALREIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGPENKVVCILLDMKGDINGMFMFLLDESITQL 100
Cdd:cd17909     1 QLDALKEIGNIGAGNAATALSQLLGKKVDMSVPEVKILPFEEVPELLGGPEEVVAGVLLRIEGDISGSILFIFPEESALK 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806 101 MLSSLFNKEESTLDEIEAIEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDICIDMVGAVLNVPMIRFSDVGDKVLFI 180
Cdd:cd17909    81 LVDLLLGREPGSTEELDEMELSALKEIGNILAGSYLNALSDFLGLTLLPSVPSLAVDMAGAILSSVLIELGQESDEALLI 160

                         170       180
                  ....*....|....*....|....*...
gi 2570605806 181 ENKFKMSDNYFTSHILMIPEMSSLREIL 208
Cdd:cd17909   161 ETEFSIEEEKIEGHFLLLPDPESLEKLL 188

chemotaxis protein CheC; includes CheC classes I, II, and III; This family contains chemotaxis protein CheC that acts as a weak CheY-P phosphatase but shows increased activity in the presence of CheD. This CheC family includes three classes: class I containing Bacillus subtilis CheC which might function as a regulator of CheD; class II CheCs that likely function as phosphatases in systems other than chemotaxis; and class III CheCs that are found chiefly in the archaeal class Halobacteria and might function similarly as class I CheCs. Class I CheCs contain two active sites with the consensus sequence ([DS]xxxExxNx(22)P), with four conserved residues thought to form the phosphatase active site; class II and class III CheCs have only one actve site.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  26 REIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGPENKVVCILLDMKGDINGMFMFLLDESITQLMLSSL 105
Cdd:cd17905     1 EIIANIGADNAARALSKLLGEEVEISLPSVRLVPLEEIPELLGGPEDEVVGVYLRVEGDINGQLLLVFPEESALELADLL 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806 106 FNKEESTLDEIEAIEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDICIDMVGAVLNVPMIRFSDVGDKVLFIENKFK 185
Cdd:cd17905    81 LGRPPGTTKELDELERSALGEVGNILGSAFLNALADLLGLELRPSPPAVVVDMAGAILEFAVAEQAAESDEVLLIETEFE 160

                         170
                  ....*....|...
gi 2570605806 186 MSDNYFTSHILMI 198
Cdd:cd17905   161 VEDSELDGHFLLL 173

chemotactic protein CheC, Class III; This family contains class III CheC proteins, present chiefly in the archaeal class Halobacteria. Sequence analysis shows that class III CheC proteins are structurally and functionally similar to class I CheCs, and not to CheX, despite the fact that both class III CheCs and CheX lack the first of the two phosphatase active sites of class I CheCs, and retain the second active site. Mutation analysis shows that the second active site is more important for function that the first one, suggesting that class III proteins arose by loss of the unnecessary first active site through mutational shift. All chemotactic archaea have a CheC homologue.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  22 IDALR---EIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGpeNKVVCILLDMKGDINGMFMFLLDE--- 95
Cdd:cd17911     2 IDKLEtfnELAREGAERAADSLSQMTGIETTVEVTKVSFVPIEDIPEEFGD--EEYVGVRVELEGGLSGYTLLLFDEesa 79

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  96 -SITQLMLSslfnkeESTLDEIEAIEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDICIDMVGAVLNvPMIRFSDVG 174
Cdd:cd17911    80 rRLAEALLP------GMGDDELSEMAESAIEELGNIMTSGFIDGWANVLGTTIDISPPTYVEDMGSAILD-PVLADLGDD 152

                         170       180       190
                  ....*....|....*....|....*....|....
gi 2570605806 175 DKVLFIENKFKMSDNYFTSHILMIPEMSSLREIL 208
Cdd:cd17911   153 DLAFVFDSRIEAVDTEIDFRIYLLPDPESLVELL 186

CheC/CheX/FliY (CXY) family phosphatases; The CXY family includes CheY-P-hydrolyzing proteins that function in bacterial chemotaxis, which involves cellular processes that control the movement of organisms toward favorable environments via rotating flagella, which in turn determines the sense of rotation by the intracellular response regulator CheY. When phosphorylated, CheY-P interacts directly with the flagellar motor, and this signal is terminated by the CXY family of phosphatases (Escherichia coli uses CheZ). CheC acts as a weak CheY-P phosphatase but increases activity in the presence of CheD. Bacillus subtilis has only CheC and FliY while many systems also have CheX. CheC and CheX appear to be primarily involved in restoring normal CheY-P levels, whereas FliY seems to act on CheY-P constitutively. Unlike CheC and CheX, FliY is localized in the flagellar switch complex, which also contains the stator-coupling protein FliG and the target of CheY-P, FliM. CheC, CheX, and FliY phosphatases share a consensus sequence ([DS]xxxExxNx(22)P) with four conserved residues thought to form the phosphatase active site. CheC class I and FliY each have two active sites, while CheC class II and III, and CheX have only one. This family also includes FliM, a component of the flagellar switch complex and a target of CheY, which lacks the phosphatase active site consensus sequence, and is not a CheY phosphatase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  27 EIGNIGSGNAITALASMINSNVEVLIPMVKILEYNeatNLLGGPENKVVCILLDMKGDINGMFMFLLDESITQLMLSSLF 106
Cdd:cd16353     2 EIGNIFGGAAATTLSGRLRTGIEPEVGSPDQVKYE---EVIRDVMIPSVVVVVGITGGIEGSAILEMRKDLAYKVLDI*M 78

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806 107 NKEESTLDEIEAIEISAIKEIGNIMASSYVNAIaSMLNMTISVSIPDICIDMVGAVLNVP 166
Cdd:cd16353    79 GGPGEPNRPLDEIELSAVGEEGNNMLGLLAQAL-SDFGQTFDISPPNVEIGPQFVIIDNP 137

flagellar motor switch protein; Reviewed

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  23 DALREIGNIGSGNAITALASMINSNVEVLIPMVKILEyneaTNLLGGPENKVVCILLDMKGDING--MFMFLLDESITQL 100
Cdd:PRK06782  231 DVLGEVANISIGSASTVLSTLLNQPVSISTPNVEAIN----VRHYDGVEVPFVILNVDFVEGLKNenVFVFTKDVALIMA 306

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....
gi 2570605806 101 MLSSLFNKEESTLDEIEAIEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDI 154
Cdd:PRK06782  307 DLMMMGTGEVDEEKELTELELSAIKEIMNQMMGHAATAMSEMFQEKIDISPPTV 360

flagellar motor switch protein FliY; This family contains the flagellar rotor protein FliY, a highly conserved and essential member of the CheC phosphatase family, that distinguishes flagellar architecture and function in different types of bacteria. Unlike CheC and CheX, FliY is localized in the flagellar switch complex, which also contains the stator-coupling protein FliG and the target of CheY-P, FliM, all present in many copies, and together corresponding structurally to the C-ring of the flagellar basal body. FliY structure resembles that of the rotor protein FliM but contains two active centers for CheY dephosphorylation. In bacteria such as Thermotogae and Bacilli, FliY is fused to FliN. It incorporates properties of the FliM/FliN rotor proteins and the CheC/CheX phosphatases to serve multiple functions in the flagellar switch. FliY seems to act on CheY-P constitutively, as compared to CheC and CheX that appear to be primarily involved in restoring normal CheY-P levels.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  16 ELDDVHIDALREIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGP-ENKVVCILLDMK--GDINGMFMFL 92
Cdd:cd17907    97 ELDELHLSAVSEAMNQMMGSAATSLSEMLGKKVDISPPEVELVDFEEELELPPLEdEDKVVKVSFRLKieDLIDSEIMQL 176

                          90
                  ....*....|....*
gi 2570605806  93 LDESITQLMLSSLFN 107
Cdd:cd17907   177 MPIDFAKELVSKLLG 191

CheC-like family; The restoration of pre-stimulus levels of the chemotactic response regulator, CheY-P, is important for allowing bacteria to respond to new environmental stimuli. The members of this family, CheC, CheX, CheA and FliY are CheY-P phosphatase. CheC appears to be primarily involved in restoring normal CheY-P levels, whereas FliY seems to act on CheY-P constitutively. CheD enhances the activity of CheC 5-fold, which is normally relatively low. In some cases, the region represented by this entry is present as multiple copies.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 2570605806 119 IEISAIKEIGNIMASSYVNAIASMLNMTISVSIPDI 154
Cdd:pfam04509   1 MELSALGEIGNILAGSAATALATLLGFKIDISPPTV 36

chemotaxis protein CheC, Class II; This family contains class II CheC proteins found in proteobacteria, which diverge from class I CheCs in sequence conservation and lack critical well-conserved residues for CheD binding. These proteins are likely to be dedicated phosphatases. The class II cheC genes are not found in chemotaxis operons, but in operons containing more archetypical two-component signaling components, non-signaling operons, or as orphans. Thus, class II CheCs appear to be involved in non-chemotactic two component systems. Class II CheCs lack the first of the two phosphatase active sites of class I CheCs, and retain the second active site of class I CheCs.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2570605806  16 ELDDVHIDALREIGNIGSGNAITALASMINSNVEVLIPMVKILEYNEATNLLGGPENKVVcILLDM-----KGDINGMFM 90
Cdd:cd17910    96 DLDELEQEALLEVGNILLNACLGSLANQLDLELSYSLPVVLEGSLEELLLLNGSDEWDYV-LLIEIdftieDRDIEGDLL 174

                          90
                  ....*....|..
gi 2570605806  91 FLLDE-SITQLM 101
Cdd:cd17910   175 LLLDEdSLDALL 186

Chemotaxis phosphatase CheX; CheX is very closely related to the CheC chemotaxis phosphatase, but it dimerizes in a different way, via a continuous beta sheet between the subunits. CheC and CheX both dephosphorylate CheY, although CheC requires binding of CheD to achieve the activity of CheX. The ability of bacteria to modulate their swimming behaviour in the presence of external chemicals (nutrients and repellents) is one of the most rudimentary behavioural responses known, but the the individual components are very sensitively tuned.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2570605806  75 VCILLDMKGDINGMFMFLLDESITQLMLSSLFNKEESTLDEIEaieiSAIKEIGNIMAssyvNAIASMLNMTISVSIP 152
Cdd:pfam13690   1 VTGIIGLAGDISGLVILSFPEALALKIASALGEDEEELDEDVL----DAVGELANMIA----GNAKSKLGEPVKLSPP 70