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MULTISPECIES: succinate dehydrogenase cytochrome B558 [Staphylococcus]

Protein Classification

succinate dehydrogenase cytochrome b558 subunit( domain architecture ID 10131273)

succinate dehydrogenase cytochrome b558 subunit is a di-heme cytochrome that is part of the enzyme complex that catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol

Graphical summary

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List of domain hits

 Name Accession Description Interval E-value
SQR_TypeB_1_TM cd03497
Succinate:quinone oxidoreductase (SQR) Type B subfamily 1, transmembrane subunit; composed of ...
 5-203 5.53e-81

Succinate:quinone oxidoreductase (SQR) Type B subfamily 1, transmembrane subunit; composed of proteins similar to Bacillus subtilis SQR. SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol. Bacillus subtilis SQR reduces low potential quinones such as menaquinone. SQR is also called succinate dehydrogenase (Sdh) or Complex II and is part of the citric acid cycle and the aerobic respiratory chain. SQR is composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are classified as Type B as they contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside on the transmembrane subunit. The transmembrane subunit of Bacillus subtilis SQR is also called Sdh cytochrome b558 subunit. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron acceptor (quinone). The reversible reduction of quinone is an essential feature of respiration, allowing transfer of electrons between respiratory complexes.


:

Pssm-ID: 239577  Cd Length: 207  Bit Score: 239.91  E-value: 5.53e-81
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   5 KNEFYLRRLHSLLGVIPIGAFLIVHLMVNHQATQGAEAFNRASGFMESLPFLIVMEFILIYIPLLYHGLFGLHIAFTAKE 84
Cdd:cd03497    1 RNEFIIRRLHSLLGVVPIGLFLIEHLLTNSSAASGPEGFNAAVNFMHSLPGLLLIEIFGIFLPLLFHAIYGIYIAFTAKS 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  85 NIGHYSLFRNWMFFFQRVSGILAFIFIAMHLWQTRLQKAFYG--------KSVDYNLMHETLQHPLWAIFYIICVIAVVF 156
Cdd:cd03497   81 NTGRYDYFRNWMYTLQRITGIILLVFIAWHVWHTRFAEALGHvdiqtpeaGEANLSAMRNALASPLMLIFYIIGVLAAVF 160

                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*..
gi 488388030 157 HFANGLWSFCVTWGFLQSKKSQRVFTWISLIVFLVISYIGVAAVIAF 203
Cdd:cd03497  161 HFANGLWTFLITWGITVSPRSQRVSTYVCLLVFVVVSFMGVAAIWAF 207
 
Name Accession Description Interval E-value
SQR_TypeB_1_TM cd03497
Succinate:quinone oxidoreductase (SQR) Type B subfamily 1, transmembrane subunit; composed of ...
 5-203 5.53e-81

Succinate:quinone oxidoreductase (SQR) Type B subfamily 1, transmembrane subunit; composed of proteins similar to Bacillus subtilis SQR. SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol. Bacillus subtilis SQR reduces low potential quinones such as menaquinone. SQR is also called succinate dehydrogenase (Sdh) or Complex II and is part of the citric acid cycle and the aerobic respiratory chain. SQR is composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are classified as Type B as they contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside on the transmembrane subunit. The transmembrane subunit of Bacillus subtilis SQR is also called Sdh cytochrome b558 subunit. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron acceptor (quinone). The reversible reduction of quinone is an essential feature of respiration, allowing transfer of electrons between respiratory complexes.


Pssm-ID: 239577  Cd Length: 207  Bit Score: 239.91  E-value: 5.53e-81
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   5 KNEFYLRRLHSLLGVIPIGAFLIVHLMVNHQATQGAEAFNRASGFMESLPFLIVMEFILIYIPLLYHGLFGLHIAFTAKE 84
Cdd:cd03497    1 RNEFIIRRLHSLLGVVPIGLFLIEHLLTNSSAASGPEGFNAAVNFMHSLPGLLLIEIFGIFLPLLFHAIYGIYIAFTAKS 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  85 NIGHYSLFRNWMFFFQRVSGILAFIFIAMHLWQTRLQKAFYG--------KSVDYNLMHETLQHPLWAIFYIICVIAVVF 156
Cdd:cd03497   81 NTGRYDYFRNWMYTLQRITGIILLVFIAWHVWHTRFAEALGHvdiqtpeaGEANLSAMRNALASPLMLIFYIIGVLAAVF 160

                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*..
gi 488388030 157 HFANGLWSFCVTWGFLQSKKSQRVFTWISLIVFLVISYIGVAAVIAF 203
Cdd:cd03497  161 HFANGLWTFLITWGITVSPRSQRVSTYVCLLVFVVVSFMGVAAIWAF 207
sdhC_b558_fam TIGR02046
succinate dehydrogenase (or fumarate reductase) cytochrome b subunit, b558 family; This family ...
 7-204 1.70e-32

succinate dehydrogenase (or fumarate reductase) cytochrome b subunit, b558 family; This family consists of the succinate dehydrogenase subunit C of Bacillus subtilis, designated cytochrome b-558, and related sequences that include a fumarate reductase subunit C. This subfamily is only weakly similar to the main group of succinate dehydrogenase cytochrome b subunits described by pfam01127, so that some members score above the gathering threshold and some do not. [Energy metabolism, TCA cycle]


Pssm-ID: 131101 [Multi-domain]  Cd Length: 214  Bit Score: 116.42  E-value: 1.70e-32
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030    7 EFYLRRLHSLLGVIPIGaFLIVHLMVNHQATQGAEAFNRASGFMESLPFLIVMEFILIYIPLLYHGLFGLHIAFTAKENI 86
Cdd:TIGR02046   2 SIGRKVVMALTGLVLLL-FLVVHMVGNLFALFGAEAFNAAAHFLRSLPFRLWLERIILFVPFILHAVYAVILSIRNKRNA 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   87 GHYSLFRN------WMFFFQRVSGILAFIFIAMHLWQTRLQKAFYG-------KSVDYNLMHETLQHPLWAIFYIICVIA 153
Cdd:TIGR02046  81 RPYRYMHKgrpgvsWASRTMRVTGIIVLIFIGWHVLDFTIGAQMGEifhmgvaRHDGYDMVVLTFSSPIMLSIYIVAMLA 160

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|....
gi 488388030  154 VVFHFANGLWSFCVTWGFLQSKKSQRV---FTWISLIVFLVISYIGVAAVIAFI 204
Cdd:TIGR02046 161 LGFHLSHGLWSAAQTLGLNVTPRSQRIktiSNVVALVIFGGFSAVPLKFILGFV 214
Sdh_cyt pfam01127
Succinate dehydrogenase/Fumarate reductase transmembrane subunit; This family includes a ...
 95-193 3.36e-06

Succinate dehydrogenase/Fumarate reductase transmembrane subunit; This family includes a transmembrane protein from both the Succinate dehydrogenase and Fumarate reductase complexes.


Pssm-ID: 426067  Cd Length: 122  Bit Score: 44.68  E-value: 3.36e-06
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   95 WMFFFQRVSGILAFIFIAMHLWQTRLQKAFYGKSVDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQS 174
Cdd:pfam01127  21 WLSILHRITGVALAVLGLIFLLLWLLLLLSLLGPESYATVVAWLASPVKLILLLLLLLALFYHAANGIRHLIWDVGFGLE 100

                          90
                  ....*....|....*....
gi 488388030  175 KKSQRVFTWISLIVFLVIS 193
Cdd:pfam01127 101 LKTVRKSGAAVLALSVVLV 119
SdhC COG2009
Succinate dehydrogenase/fumarate reductase, cytochrome b subunit [Energy production and ...
 101-193 5.26e-06

Succinate dehydrogenase/fumarate reductase, cytochrome b subunit [Energy production and conversion];


Pssm-ID: 441612  Cd Length: 128  Bit Score: 44.00  E-value: 5.26e-06
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030 101 RVSGILAFIFIAMHLWQtrLQKAFYGKSvDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQSKKSQRV 180
Cdd:COG2009   29 RITGVALFLGLPLLVWW--LAASASSPE-AFAAVQAFLGSPLGKLVLLGLTWALLYHLLAGIRHLLWDFGYGFELETARR 105

                         90
                 ....*....|...
gi 488388030 181 FTWISLIVFLVIS 193
Cdd:COG2009  106 SAWVVLVLSVVLT 118
PRK13554 PRK13554
fumarate reductase cytochrome b-556 subunit; Provisional
 12-204 1.29e-04

fumarate reductase cytochrome b-556 subunit; Provisional


Pssm-ID: 237424  Cd Length: 241  Bit Score: 41.66  E-value: 1.29e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  12 RLHSLLGVIpIGAFLIVHLMVNHQATQGAEAFNRASGFMES---------LPFLIVMEFILIYIPLLYHGLFGLHiAFTA 82
Cdd:PRK13554  26 KLQSATGIM-LGCFLLLHMHFESSILLGKEAFYHVVQFLEGgmfsstghgFPIVTKVFSVFMLLVVIVHAAVALR-RFPA 103

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  83 KenIGHYSLFRNWM----------FFFQRVSGILAFIFIAMHLWQTRLQKafygkSVDYNLMHETLQHPLWAIFYIICVI 152
Cdd:PRK13554 104 Q--LGQWRALRSHMgsikhkdthaWFWQLITGFILFFLVPVHLFTMILNP-----EIGPHLSAERVYHDNAWLLYALLLP 176

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|..
gi 488388030 153 AVVFHFANGLWSFCVTWGFLQSKKSQRVFTWIsLIVFLVIsyIGVAAVIAFI 204
Cdd:PRK13554 177 AVVIHAMIGLYRVAVKWGLTTNRSGLRKVAKV-LIIYLLC--LGTLSLVSYI 225
 
Name Accession Description Interval E-value
SQR_TypeB_1_TM cd03497
Succinate:quinone oxidoreductase (SQR) Type B subfamily 1, transmembrane subunit; composed of ...
 5-203 5.53e-81

Succinate:quinone oxidoreductase (SQR) Type B subfamily 1, transmembrane subunit; composed of proteins similar to Bacillus subtilis SQR. SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol. Bacillus subtilis SQR reduces low potential quinones such as menaquinone. SQR is also called succinate dehydrogenase (Sdh) or Complex II and is part of the citric acid cycle and the aerobic respiratory chain. SQR is composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are classified as Type B as they contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside on the transmembrane subunit. The transmembrane subunit of Bacillus subtilis SQR is also called Sdh cytochrome b558 subunit. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron acceptor (quinone). The reversible reduction of quinone is an essential feature of respiration, allowing transfer of electrons between respiratory complexes.


Pssm-ID: 239577  Cd Length: 207  Bit Score: 239.91  E-value: 5.53e-81
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   5 KNEFYLRRLHSLLGVIPIGAFLIVHLMVNHQATQGAEAFNRASGFMESLPFLIVMEFILIYIPLLYHGLFGLHIAFTAKE 84
Cdd:cd03497    1 RNEFIIRRLHSLLGVVPIGLFLIEHLLTNSSAASGPEGFNAAVNFMHSLPGLLLIEIFGIFLPLLFHAIYGIYIAFTAKS 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  85 NIGHYSLFRNWMFFFQRVSGILAFIFIAMHLWQTRLQKAFYG--------KSVDYNLMHETLQHPLWAIFYIICVIAVVF 156
Cdd:cd03497   81 NTGRYDYFRNWMYTLQRITGIILLVFIAWHVWHTRFAEALGHvdiqtpeaGEANLSAMRNALASPLMLIFYIIGVLAAVF 160

                        170       180       190       200
                 ....*....|....*....|....*....|....*....|....*..
gi 488388030 157 HFANGLWSFCVTWGFLQSKKSQRVFTWISLIVFLVISYIGVAAVIAF 203
Cdd:cd03497  161 HFANGLWTFLITWGITVSPRSQRVSTYVCLLVFVVVSFMGVAAIWAF 207
sdhC_b558_fam TIGR02046
succinate dehydrogenase (or fumarate reductase) cytochrome b subunit, b558 family; This family ...
 7-204 1.70e-32

succinate dehydrogenase (or fumarate reductase) cytochrome b subunit, b558 family; This family consists of the succinate dehydrogenase subunit C of Bacillus subtilis, designated cytochrome b-558, and related sequences that include a fumarate reductase subunit C. This subfamily is only weakly similar to the main group of succinate dehydrogenase cytochrome b subunits described by pfam01127, so that some members score above the gathering threshold and some do not. [Energy metabolism, TCA cycle]


Pssm-ID: 131101 [Multi-domain]  Cd Length: 214  Bit Score: 116.42  E-value: 1.70e-32
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030    7 EFYLRRLHSLLGVIPIGaFLIVHLMVNHQATQGAEAFNRASGFMESLPFLIVMEFILIYIPLLYHGLFGLHIAFTAKENI 86
Cdd:TIGR02046   2 SIGRKVVMALTGLVLLL-FLVVHMVGNLFALFGAEAFNAAAHFLRSLPFRLWLERIILFVPFILHAVYAVILSIRNKRNA 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   87 GHYSLFRN------WMFFFQRVSGILAFIFIAMHLWQTRLQKAFYG-------KSVDYNLMHETLQHPLWAIFYIICVIA 153
Cdd:TIGR02046  81 RPYRYMHKgrpgvsWASRTMRVTGIIVLIFIGWHVLDFTIGAQMGEifhmgvaRHDGYDMVVLTFSSPIMLSIYIVAMLA 160

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|....
gi 488388030  154 VVFHFANGLWSFCVTWGFLQSKKSQRV---FTWISLIVFLVISYIGVAAVIAFI 204
Cdd:TIGR02046 161 LGFHLSHGLWSAAQTLGLNVTPRSQRIktiSNVVALVIFGGFSAVPLKFILGFV 214
SQR_QFR_TypeB_TM cd03526
Succinate:quinone oxidoreductase (SQR) and Quinol:fumarate reductase (QFR) Type B subfamily, ...
 10-202 3.95e-30

Succinate:quinone oxidoreductase (SQR) and Quinol:fumarate reductase (QFR) Type B subfamily, transmembrane subunit; SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol, while QFR catalyzes the reverse reaction. SQR, also called succinate dehydrogenase or Complex II, is part of the citric acid cycle and the aerobic respiratory chain, while QFR is involved in anaerobic respiration with fumarate as the terminal electron acceptor. SQR and QFR share a common subunit arrangement, composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Type B proteins contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside in the transmembrane subunits. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron donor/acceptor (quinol or quinone). The reversible reduction of quinone is an essential feature of respiration, allowing the transfer of electrons between respiratory complexes.


Pssm-ID: 239602  Cd Length: 199  Bit Score: 110.00  E-value: 3.95e-30
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  10 LRRLHSLLGVIpIGAFLIVHLMVNHQATQGAEAFNRASGFMESLPFLIVMEFILIYIPLLYHGLFGLHIAF---TAKENI 86
Cdd:cd03526    1 LDWLQSATGLF-LGLFMIGHLFFNSTILLGDNVMNWVAKKFELLPIVVSFLAAFIFAVFIAHAFLGVRKFPiyrQALTFK 79

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  87 GHYSLF--RNWMFFFQRVSGILAFIFIAMHLWQTRLQkAFYGKSVDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWS 164
Cdd:cd03526   80 THKDLMhgDTTLWWIQAMTGFAMLFFGSVHLYIMMTQ-AQPDRTIGFVMSSNRMSSEWMWPLYIVLLFAVELHGSVGLYS 158

                        170       180       190       200
                 ....*....|....*....|....*....|....*....|.
gi 488388030 165 FCVTWGFLQSK---KSQRVFTWISLIVFLVISYIGVAAVIA 202
Cdd:cd03526  159 FAVTWGWFDGEtpdKSRANLKKLKTLMSAFLSVLGLLTFGA 199
SQR_TypeB_2_TM cd03498
Succinate:quinone oxidoreductase (SQR)-like Type B subfamily 2, transmembrane subunit; ...
 25-203 8.22e-14

Succinate:quinone oxidoreductase (SQR)-like Type B subfamily 2, transmembrane subunit; composed of proteins with similarity to the SQRs of Geobacter metallireducens and Corynebacterium glutamicum. SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol. C. glutamicum SQR reduces low potential quinones such as menaquinone. SQR is also called succinate dehydrogenase (Sdh) or Complex II and is part of the citric acid cycle and the aerobic respiratory chain. SQR is composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are classified as Type B as they contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside in the transmembrane subunit. The transmembrane subunit of members of this subfamily is also called Sdh cytochrome b558 subunit based on the Bacillus subtilis protein. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron acceptor (quinone). The reversible reduction of quinone is an essential feature of respiration, allowing transfer of electrons between respiratory complexes. Proteins in this subfamily from G. metallireducens and G. sulfurreducens are bifunctional enzymes with SQR and QFR activities.


Pssm-ID: 239578  Cd Length: 209  Bit Score: 66.89  E-value: 8.22e-14
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  25 FLIVHLMVNHQATQGAEAFNRASGFMESL-PFLIVMEFILIYIPLLyHGLFGLHI----------AFTAKENIGHYSLFR 93
Cdd:cd03498   15 FLLVHLLGNLKIFFGPEAFNAYAEFLHTLnPLLWIARLVLLVAAVL-HIVFGLQLtirnraarpvRYAVKNRKKLASLAS 93

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  94 NWMfffqRVSGILAFIFIAMHLWQTRLQKAFYGKSVD-------YNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFC 166
Cdd:cd03498   94 RTM----IWSGLIILLFIILHLLDFTFGVVGPVSPPMgvgrgdvYELLVASFQQPWIAALYVLAMVALGLHLSHGFWSAF 169

                        170       180       190
                 ....*....|....*....|....*....|....*....
gi 488388030 167 VTWGFLQSkKSQRVFTWISLIVFLVIS--YIGVAAVIAF 203
Cdd:cd03498  170 QTLGLNNP-RYRPALKAVGRVVAILIAggFISIPLLILF 207
SQR_QFR_TM cd03493
Succinate:quinone oxidoreductase (SQR) and Quinol:fumarate reductase (QFR) family, ...
 98-198 1.52e-08

Succinate:quinone oxidoreductase (SQR) and Quinol:fumarate reductase (QFR) family, transmembrane subunits; SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol, while QFR catalyzes the reverse reaction. SQR, also called succinate dehydrogenase or Complex II, is part of the citric acid cycle and the aerobic respiratory chain, while QFR is involved in anaerobic respiration with fumarate as the terminal electron acceptor. SQRs may reduce either high or low potential quinones while QFRs oxidize only low potential quinols. SQR and QFR share a common subunit arrangement, composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit(s) containing the electron donor/acceptor (quinol or quinone). The reversible reduction of quinone is an essential feature of respiration, allowing the transfer of electrons between respiratory complexes. SQRs and QFRs can be classified into five types (A-E) according to the number of their hydrophobic subunits and heme groups. This classification is consistent with the characteristics and phylogeny of the catalytic and iron-sulfur subunits. Type E proteins, e.g. non-classical archael SQRs, contain atypical transmembrane subunits and are not included in this hierarchy. The heme and quinone binding sites reside in the transmembrane subunits. Although succinate oxidation and fumarate reduction are carried out by separate enzymes in most organisms, some bifunctional enzymes that exhibit both SQR and QFR activities exist.


Pssm-ID: 239573  Cd Length: 98  Bit Score: 50.36  E-value: 1.52e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  98 FFQRVSGILAFIFIAMHLWQTRLQKAFYGksvDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQSKKS 177
Cdd:cd03493    1 ILHRITGVALLLFLPLHLLGLLALLGGPY---AFAEVVAFLSSPLGKLLYLLLLLALLYHALNGIRHLIWDYGKGLELKL 77

                         90       100
                 ....*....|....*....|.
gi 488388030 178 QRVFTWISLIVFLVISYIGVA 198
Cdd:cd03493   78 RKALGYAVLALSVLLTVLLLF 98
QFR_TypeB_TM cd00581
Quinol:fumarate reductase (QFR) Type B subfamily, transmembrane subunit; QFR couples the ...
 10-204 5.48e-08

Quinol:fumarate reductase (QFR) Type B subfamily, transmembrane subunit; QFR couples the reduction of fumarate to succinate to the oxidation of quinol to quinone, the opposite reaction to that catalyzed by the related protein, succinate:quinone oxidoreductase (SQR). QFRs oxidize low potential quinols such as menaquinol and rhodoquinol and are involved in anaerobic respiration with fumarate as the terminal electron acceptor. SQR and QFR share a common subunit arrangement, composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are classified as Type B as they contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside in the transmembrane subunit. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron donor (quinol). The Type B enzyme from Desulfovibrio gigas is capable of fumarate reduction and succinate oxidation.


Pssm-ID: 238325  Cd Length: 206  Bit Score: 50.79  E-value: 5.48e-08
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  10 LRRLHSLLGVIpIGAFLIVHLMVNHQATQGAEAFNRASGFME-------SLPFLIVMEFILIYIPLLYHGLFGLH-IAFT 81
Cdd:cd00581    1 LDFLQSATGLF-LALFMWAHMLFVSSILLGKEAMYWVARFFEgafffghGYPWVVSVVAAIVFALFVAHAFLALRkFPAN 79

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  82 AKENI---GHYSLFRN---WMFFFQRVSGILAFIFIAMHLWQTRLQKAFYGKSvdynLMHETLQHPLWAIFYIICVIAVV 155
Cdd:cd00581   80 YRQWRafrRHMQLMKHgdtSLWWIQAVTGFVLFFLASAHLYEMLTNPEIIGPH----TSAYRVVHGGWWLLYLALLPAVE 155

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|
gi 488388030 156 FHFANGLWSFCVTWGFLQSKKSQRVFTWI-SLIVFLVIsyIGVAAVIAFI 204
Cdd:cd00581  156 LHGGIGLYRLAVKWGWFASESRKRLRRIKnVLSAFFLV--LGLLTLLAYI 203
succ_dehyd_cytB TIGR02970
succinate dehydrogenase, cytochrome b556 subunit; In E. coli and many other bacteria, two ...
 95-195 9.13e-07

succinate dehydrogenase, cytochrome b556 subunit; In E. coli and many other bacteria, two small, hydrophobic, mutually homologous subunits of succinate dehydrogenase, a TCA cycle enzyme, are SdhC and SdhD. This family is the SdhC, the cytochrome b subunit, called b556 in bacteria and b560 in mitochondria. SdhD (see TIGR02968) is called the hydrophobic membrane anchor subunit, although both SdhC and SdhD participate in anchoring the complex. In some bacteria, this cytochrome b subunit is replaced my a member of the cytochrome b558 family (see TIGR02046). [Energy metabolism, TCA cycle]


Pssm-ID: 274370  Cd Length: 120  Bit Score: 46.02  E-value: 9.13e-07
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   95 WMFFFQRVSGILAFIFIAMHLWQtrLQKAFYGKSVdYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQS 174
Cdd:TIGR02970  19 ILSILHRITGVLLFFGLPFLLWW--LSLSLSSPES-FATVHALLSSPLGKLILWGLLWALLYHLLAGIRHLLWDLGYGLE 95

                          90       100
                  ....*....|....*....|.
gi 488388030  175 KKSQRVFTWISLIVFLVISYI 195
Cdd:TIGR02970  96 LKSARISAWVVLVLSLVLTIL 116
Sdh_cyt pfam01127
Succinate dehydrogenase/Fumarate reductase transmembrane subunit; This family includes a ...
 95-193 3.36e-06

Succinate dehydrogenase/Fumarate reductase transmembrane subunit; This family includes a transmembrane protein from both the Succinate dehydrogenase and Fumarate reductase complexes.


Pssm-ID: 426067  Cd Length: 122  Bit Score: 44.68  E-value: 3.36e-06
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   95 WMFFFQRVSGILAFIFIAMHLWQTRLQKAFYGKSVDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQS 174
Cdd:pfam01127  21 WLSILHRITGVALAVLGLIFLLLWLLLLLSLLGPESYATVVAWLASPVKLILLLLLLLALFYHAANGIRHLIWDVGFGLE 100

                          90
                  ....*....|....*....
gi 488388030  175 KKSQRVFTWISLIVFLVIS 193
Cdd:pfam01127 101 LKTVRKSGAAVLALSVVLV 119
SQR_TypeA_SdhC_like cd03501
Succinate:quinone oxidoreductase (SQR) Type A subfamily, Succinate dehydrogenase C (SdhC)-like ...
 95-197 5.22e-06

Succinate:quinone oxidoreductase (SQR) Type A subfamily, Succinate dehydrogenase C (SdhC)-like subunit; SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol. Members of this subfamily reduce low potential quinones such as menaquinone and thermoplasmaquinone. SQR is also called succinate dehydrogenase or Complex II, and is part of the citric acid cycle and the aerobic respiratory chain. SQR is composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are similar to the Thermoplasma acidophilum SQR and are classified as Type A because they contain two transmembrane subunits as well as two heme groups. Although there are no structures available for this subfamily, the presence of two hemes has been proven spectroscopically for T. acidophilum. The two membrane anchor subunits are similar to the SdhD and SdhC subunits of bacterial SQRs, which contain heme and quinone binding sites. The two-electron oxidation of succinate in the flavoprotein active site is coupled to the two-electron reduction of quinone in the membrane anchor subunits via electron transport through FAD and three iron-sulfur centers. The reversible reduction of quinone is an essential feature of respiration, allowing transfer of electrons between respiratory complexes.


Pssm-ID: 239581  Cd Length: 101  Bit Score: 43.41  E-value: 5.22e-06
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  95 WMFFFQRVSGILAFIFIAMHLWQTRLqkAFYGKSVdYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQS 174
Cdd:cd03501    2 WAWVLHRITGVVILFYLFLHVLDLSS--LRRGPET-YNAVIATYKSPIFKLGEFGLVAAVVFHALNGIRLILVDFGSGGP 78

                         90       100
                 ....*....|....*....|...
gi 488388030 175 KKSQRVFtWISLIVFLVISYIGV 197
Cdd:cd03501   79 RYQRQLF-YIVLVLTVVLIVAAG 100
SdhC COG2009
Succinate dehydrogenase/fumarate reductase, cytochrome b subunit [Energy production and ...
 101-193 5.26e-06

Succinate dehydrogenase/fumarate reductase, cytochrome b subunit [Energy production and conversion];


Pssm-ID: 441612  Cd Length: 128  Bit Score: 44.00  E-value: 5.26e-06
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030 101 RVSGILAFIFIAMHLWQtrLQKAFYGKSvDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGFLQSKKSQRV 180
Cdd:COG2009   29 RITGVALFLGLPLLVWW--LAASASSPE-AFAAVQAFLGSPLGKLVLLGLTWALLYHLLAGIRHLLWDFGYGFELETARR 105

                         90
                 ....*....|...
gi 488388030 181 FTWISLIVFLVIS 193
Cdd:COG2009  106 SAWVVLVLSVVLT 118
SdhD COG2142
Succinate dehydrogenase, hydrophobic anchor subunit [Energy production and conversion];
95-163 1.89e-05

Succinate dehydrogenase, hydrophobic anchor subunit [Energy production and conversion];


Pssm-ID: 441745  Cd Length: 124  Bit Score: 42.51  E-value: 1.89e-05
                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 488388030  95 WMFFFQRVSGILAFIFIAMHLWQtrlqkAFYGKSVDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLW 163
Cdd:COG2142   21 HHWLLQRVTAVALVVLVLWFLFF-----LLSLPGADYAEVAAWFASPFWAILTLLFLLSALYHAWLGLR 84
SQR_TypeA_SdhD_like cd03500
Succinate:quinone oxidoreductase (SQR) Type A subfamily, Succinate dehydrogenase D (SdhD)-like ...
 95-202 2.66e-05

Succinate:quinone oxidoreductase (SQR) Type A subfamily, Succinate dehydrogenase D (SdhD)-like subunit; SQR catalyzes the oxidation of succinate to fumarate coupled to the reduction of quinone to quinol. Members of this subfamily reduce low potential quinones such as menaquinone and thermoplasmaquinone. SQR is also called succinate dehydrogenase or Complex II, and is part of the citric acid cycle and the aerobic respiratory chain. SQR is composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are similar to the Thermoplasma acidophilum SQR and are classified as Type A because they contain two transmembrane subunits as well as two heme groups. Although there are no structures available for this subfamily, the presence of two hemes has been proven spectroscopically for T. acidophilum. The two membrane anchor subunits are similar to the SdhD and SdhC subunits of bacterial SQRs, which contain heme and quinone binding sites. The two-electron oxidation of succinate in the flavoprotein active site is coupled to the two-electron reduction of quinone in the membrane anchor subunits via electron transport through FAD and three iron-sulfur centers. The reversible reduction of quinone is an essential feature of respiration, allowing transfer of electrons between respiratory complexes.


Pssm-ID: 239580  Cd Length: 106  Bit Score: 41.88  E-value: 2.66e-05
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  95 WMFFFQRVSGILAFIFIAMHLWQTRLQkaFYGKSVDYNLMHETLQHPLWAIFYIICVIAVVFHFANGLWSFCVTWGflQS 174
Cdd:cd03500    3 LAWLFQRITGVFLVFLLAGHFWVQHMD--NGGDVIDFAFVANRLASPLWKVWDLLLLVLALLHGGNGLRNILLDYV--RR 78

                         90       100
                 ....*....|....*....|....*...
gi 488388030 175 KKSQRVFTWISLIVFLVISYIGVAAVIA 202
Cdd:cd03500   79 PRLRRAVKGLLYVAGLLLIVLGTYVIFA 106
PRK13554 PRK13554
fumarate reductase cytochrome b-556 subunit; Provisional
 12-204 1.29e-04

fumarate reductase cytochrome b-556 subunit; Provisional


Pssm-ID: 237424  Cd Length: 241  Bit Score: 41.66  E-value: 1.29e-04
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  12 RLHSLLGVIpIGAFLIVHLMVNHQATQGAEAFNRASGFMES---------LPFLIVMEFILIYIPLLYHGLFGLHiAFTA 82
Cdd:PRK13554  26 KLQSATGIM-LGCFLLLHMHFESSILLGKEAFYHVVQFLEGgmfsstghgFPIVTKVFSVFMLLVVIVHAAVALR-RFPA 103

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030  83 KenIGHYSLFRNWM----------FFFQRVSGILAFIFIAMHLWQTRLQKafygkSVDYNLMHETLQHPLWAIFYIICVI 152
Cdd:PRK13554 104 Q--LGQWRALRSHMgsikhkdthaWFWQLITGFILFFLVPVHLFTMILNP-----EIGPHLSAERVYHDNAWLLYALLLP 176

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|..
gi 488388030 153 AVVFHFANGLWSFCVTWGFLQSKKSQRVFTWIsLIVFLVIsyIGVAAVIAFI 204
Cdd:PRK13554 177 AVVIHAMIGLYRVAVKWGLTTNRSGLRKVAKV-LIIYLLC--LGTLSLVSYI 225
SdhC COG2009
Succinate dehydrogenase/fumarate reductase, cytochrome b subunit [Energy production and ...
 8-115 6.69e-03

Succinate dehydrogenase/fumarate reductase, cytochrome b subunit [Energy production and conversion];


Pssm-ID: 441612  Cd Length: 128  Bit Score: 35.53  E-value: 6.69e-03
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 488388030   8 FYLRRLHSLLGVIpIGAFLIVHLMVNHQATQGAEAFNRASGFMESlPFLIVMEFILIYiPLLYHGLFGL-------HIAF 80
Cdd:COG2009   22 MIVSILHRITGVA-LFLGLPLLVWWLAASASSPEAFAAVQAFLGS-PLGKLVLLGLTW-ALLYHLLAGIrhllwdfGYGF 98

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 488388030  81 TAKENighyslfRNWMFFFQRVSGILAFIFIAMHL 115
Cdd:COG2009   99 ELETA-------RRSAWVVLVLSVVLTVLLGVVLW 126
 
Blast search parameters
Data Source: Precalculated data, version = cdd.v.3.21
Preset Options:Database: CDSEARCH/cdd   Low complexity filter: no  Composition Based Adjustment: yes   E-value threshold: 0.01

References:

  • Wang J et al. (2023), "The conserved domain database in 2023", Nucleic Acids Res.51(D)384-8.
  • Lu S et al. (2020), "The conserved domain database in 2020", Nucleic Acids Res.48(D)265-8.
  • Marchler-Bauer A et al. (2017), "CDD/SPARCLE: functional classification of proteins via subfamily domain architectures.", Nucleic Acids Res.45(D)200-3.
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