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Protein

Sulfite reductase [NADPH] flavoprotein alpha-component

Gene

cysJ

Organism
Escherichia coli (strain K12)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Component of the sulfite reductase complex that catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate. The flavoprotein component catalyzes the electron flow from NADPH -> FAD -> FMN to the hemoprotein component.UniRule annotation

Catalytic activityi

H2S + 3 NADP+ + 3 H2O = sulfite + 3 NADPH.UniRule annotation1 Publication

Cofactori

Protein has several cofactor binding sites:
  • FADUniRule annotation1 PublicationNote: Binds 1 FAD per subunit.UniRule annotation1 Publication
  • FMNUniRule annotation1 PublicationNote: Binds 1 FMN per subunit.UniRule annotation1 Publication

Pathwayi: hydrogen sulfide biosynthesis

This protein is involved in step 1 of the subpathway that synthesizes hydrogen sulfide from sulfite (NADPH route).UniRule annotation
Proteins known to be involved in this subpathway in this organism are:
  1. Sulfite reductase [NADPH] hemoprotein beta-component (cysI), Sulfite reductase [NADPH] flavoprotein alpha-component (cysJ)
This subpathway is part of the pathway hydrogen sulfide biosynthesis, which is itself part of Sulfur metabolism.
View all proteins of this organism that are known to be involved in the subpathway that synthesizes hydrogen sulfide from sulfite (NADPH route), the pathway hydrogen sulfide biosynthesis and in Sulfur metabolism.

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Binding sitei322 – 3221FADUniRule annotation1 Publication
Binding sitei356 – 3561FAD; via carbonyl oxygenUniRule annotation1 Publication
Binding sitei410 – 4101FADUniRule annotation1 Publication
Binding sitei561 – 5611NADPUniRule annotation1 Publication
Binding sitei599 – 5991FADUniRule annotation1 Publication

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi70 – 756FMNUniRule annotation1 Publication
Nucleotide bindingi117 – 1204FMNUniRule annotation1 Publication
Nucleotide bindingi153 – 16210FMNUniRule annotation1 Publication
Nucleotide bindingi386 – 3894FADUniRule annotation1 Publication
Nucleotide bindingi404 – 4063FADUniRule annotation1 Publication
Nucleotide bindingi419 – 4224FADUniRule annotation1 Publication
Nucleotide bindingi519 – 5202NADPUniRule annotation1 Publication
Nucleotide bindingi525 – 5295NADPUniRule annotation1 Publication

GO - Molecular functioni

  • flavin adenine dinucleotide binding Source: EcoCyc
  • FMN binding Source: EcoCyc
  • riboflavin reductase (NADPH) activity Source: EcoCyc
  • sulfite reductase (NADPH) activity Source: UniProtKB-HAMAP

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Oxidoreductase

Keywords - Biological processi

Amino-acid biosynthesis, Cysteine biosynthesis, Electron transport, Transport

Keywords - Ligandi

FAD, Flavoprotein, FMN, NADP

Enzyme and pathway databases

BioCyciEcoCyc:ALPHACOMP-MONOMER.
ECOL316407:JW2734-MONOMER.
MetaCyc:ALPHACOMP-MONOMER.
BRENDAi1.8.1.2. 2026.
UniPathwayiUPA00140; UER00207.

Names & Taxonomyi

Protein namesi
Recommended name:
Sulfite reductase [NADPH] flavoprotein alpha-componentUniRule annotation (EC:1.8.1.2UniRule annotation1 Publication)
Short name:
SiR-FPUniRule annotation
Gene namesi
Name:cysJUniRule annotation
Ordered Locus Names:b2764, JW2734
OrganismiEscherichia coli (strain K12)
Taxonomic identifieri83333 [NCBI]
Taxonomic lineageiBacteriaProteobacteriaGammaproteobacteriaEnterobacterialesEnterobacteriaceaeEscherichia
Proteomesi
  • UP000000318 Componenti: Chromosome
  • UP000000625 Componenti: Chromosome

Organism-specific databases

EcoGeneiEG10191. cysJ.

Subcellular locationi

GO - Cellular componenti

  • sulfite reductase complex (NADPH) Source: EcoCyc
Complete GO annotation...

Pathology & Biotechi

Chemistry

DrugBankiDB03147. Flavin adenine dinucleotide.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methionineiRemoved
Chaini2 – 599598Sulfite reductase [NADPH] flavoprotein alpha-componentPRO_0000199923Add
BLAST

Proteomic databases

EPDiP38038.
PaxDbiP38038.

Interactioni

Subunit structurei

Alpha(8)-beta8. The alpha component is a flavoprotein, the beta component is a hemoprotein.UniRule annotation2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
ycbXP758634EBI-544440,EBI-544422

Protein-protein interaction databases

BioGridi4262283. 213 interactions.
DIPiDIP-9381N.
IntActiP38038. 3 interactions.
MINTiMINT-1239442.
STRINGi511145.b2764.

Structurei

Secondary structure

1
599
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi65 – 695Combined sources
Beta strandi71 – 733Combined sources
Helixi74 – 8916Combined sources
Beta strandi94 – 974Combined sources
Helixi98 – 1003Combined sources
Helixi103 – 1086Combined sources
Beta strandi110 – 1178Combined sources
Helixi120 – 1223Combined sources
Helixi126 – 1283Combined sources
Helixi129 – 1357Combined sources
Beta strandi147 – 1537Combined sources
Beta strandi158 – 1603Combined sources
Helixi163 – 17513Combined sources
Beta strandi178 – 1814Combined sources
Beta strandi184 – 1863Combined sources
Helixi191 – 20616Combined sources
Beta strandi233 – 2353Combined sources
Beta strandi237 – 24610Combined sources
Beta strandi253 – 26210Combined sources
Beta strandi275 – 2784Combined sources
Helixi284 – 29310Combined sources
Beta strandi300 – 3045Combined sources
Beta strandi307 – 3104Combined sources
Helixi311 – 3188Combined sources
Helixi326 – 33611Combined sources
Turni339 – 3413Combined sources
Helixi342 – 3443Combined sources
Helixi349 – 3579Combined sources
Helixi360 – 3667Combined sources
Helixi373 – 3797Combined sources
Beta strandi386 – 3905Combined sources
Turni394 – 3963Combined sources
Beta strandi399 – 4079Combined sources
Beta strandi409 – 4124Combined sources
Beta strandi415 – 4184Combined sources
Helixi420 – 4278Combined sources
Beta strandi434 – 4407Combined sources
Beta strandi455 – 4584Combined sources
Helixi461 – 4644Combined sources
Helixi465 – 47713Combined sources
Beta strandi483 – 4908Combined sources
Helixi492 – 4954Combined sources
Helixi499 – 5079Combined sources
Beta strandi513 – 5186Combined sources
Beta strandi521 – 5244Combined sources
Helixi528 – 5347Combined sources
Helixi536 – 5449Combined sources
Beta strandi548 – 5547Combined sources
Turni555 – 5573Combined sources
Helixi558 – 57215Combined sources
Turni573 – 5753Combined sources
Helixi578 – 59013Combined sources
Beta strandi594 – 5996Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1DDGX-ray2.01A/B226-599[»]
1DDIX-ray2.51A226-599[»]
1YKGNMR-A53-219[»]
DisProtiDP00190.
ProteinModelPortaliP38038.
SMRiP38038. Positions 64-599.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP38038.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini64 – 202139Flavodoxin-likeUniRule annotationAdd
BLAST
Domaini234 – 448215FAD-binding FR-typeUniRule annotationAdd
BLAST

Sequence similaritiesi

Belongs to the NADPH-dependent sulphite reductase flavoprotein subunit CysJ family.UniRule annotation
In the N-terminal section; belongs to the flavodoxin family.UniRule annotation
In the C-terminal section; belongs to the flavoprotein pyridine nucleotide cytochrome reductase family.UniRule annotation
Contains 1 FAD-binding FR-type domain.UniRule annotation
Contains 1 flavodoxin-like domain.UniRule annotation

Phylogenomic databases

eggNOGiENOG4107EER. Bacteria.
COG0369. LUCA.
HOGENOMiHOG000282025.
InParanoidiP38038.
KOiK00380.
OMAiGVWYEND.
OrthoDBiEOG6CVV7G.
PhylomeDBiP38038.

Family and domain databases

Gene3Di1.20.990.10. 1 hit.
3.40.50.360. 1 hit.
HAMAPiMF_01541. CysJ.
InterProiIPR010199. CysJ.
IPR029758. CysJ_Proteobact.
IPR003097. FAD-binding_1.
IPR017927. Fd_Rdtase_FAD-bd.
IPR001094. Flavdoxin-like.
IPR008254. Flavodoxin/NO_synth.
IPR001709. Flavoprot_Pyr_Nucl_cyt_Rdtase.
IPR029039. Flavoprotein-like_dom.
IPR023173. NADPH_Cyt_P450_Rdtase_dom3.
IPR001433. OxRdtase_FAD/NAD-bd.
IPR017938. Riboflavin_synthase-like_b-brl.
[Graphical view]
PfamiPF00667. FAD_binding_1. 1 hit.
PF00258. Flavodoxin_1. 1 hit.
PF00175. NAD_binding_1. 1 hit.
[Graphical view]
PIRSFiPIRSF000207. SiR-FP_CysJ. 1 hit.
PRINTSiPR00369. FLAVODOXIN.
PR00371. FPNCR.
SUPFAMiSSF52218. SSF52218. 1 hit.
SSF63380. SSF63380. 1 hit.
TIGRFAMsiTIGR01931. cysJ. 1 hit.
PROSITEiPS51384. FAD_FR. 1 hit.
PS50902. FLAVODOXIN_LIKE. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

P38038-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MTTQVPPSAL LPLNPEQLAR LQAATTDLTP TQLAWVSGYF WGVLNQQPAA
60 70 80 90 100
LAATPAPAAE MPGITIISAS QTGNARRVAE ALRDDLLAAK LNVKLVNAGD
110 120 130 140 150
YKFKQIASEK LLIVVTSTQG EGEPPEEAVA LHKFLFSKKA PKLENTAFAV
160 170 180 190 200
FSLGDSSYEF FCQSGKDFDS KLAELGGERL LDRVDADVEY QAAASEWRAR
210 220 230 240 250
VVDALKSRAP VAAPSQSVAT GAVNEIHTSP YSKDAPLVAS LSVNQKITGR
260 270 280 290 300
NSEKDVRHIE IDLGDSGMRY QPGDALGVWY QNDPALVKEL VELLWLKGDE
310 320 330 340 350
PVTVEGKTLP LNEALQWHFE LTVNTANIVE NYATLTRSET LLPLVGDKAK
360 370 380 390 400
LQHYAATTPI VDMVRFSPAQ LDAEALINLL RPLTPRLYSI ASSQAEVENE
410 420 430 440 450
VHVTVGVVRY DVEGRARAGG ASSFLADRVE EEGEVRVFIE HNDNFRLPAN
460 470 480 490 500
PETPVIMIGP GTGIAPFRAF MQQRAADEAP GKNWLFFGNP HFTEDFLYQV
510 520 530 540 550
EWQRYVKDGV LTRIDLAWSR DQKEKVYVQD KLREQGAELW RWINDGAHIY
560 570 580 590
VCGDANRMAK DVEQALLEVI AEFGGMDTEA ADEFLSELRV ERRYQRDVY
Length:599
Mass (Da):66,270
Last modified:January 23, 2007 - v4
Checksum:i6B39EF5C25265113
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti156 – 1561S → T in AAA23650 (PubMed:2550423).Curated
Sequence conflicti268 – 2681M → L in AAA23650 (PubMed:2550423).Curated
Sequence conflicti508 – 5081D → E in AAA23650 (PubMed:2550423).Curated

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M23008 Genomic DNA. Translation: AAA23650.1.
U29579 Genomic DNA. Translation: AAA69274.1.
U00096 Genomic DNA. Translation: AAC75806.1.
AP009048 Genomic DNA. Translation: BAE76841.1.
PIRiH65057.
RefSeqiNP_417244.1. NC_000913.3.
WP_000211913.1. NZ_LN832404.1.

Genome annotation databases

EnsemblBacteriaiAAC75806; AAC75806; b2764.
BAE76841; BAE76841; BAE76841.
GeneIDi947239.
KEGGiecj:JW2734.
eco:b2764.
PATRICi32120940. VBIEscCol129921_2862.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M23008 Genomic DNA. Translation: AAA23650.1.
U29579 Genomic DNA. Translation: AAA69274.1.
U00096 Genomic DNA. Translation: AAC75806.1.
AP009048 Genomic DNA. Translation: BAE76841.1.
PIRiH65057.
RefSeqiNP_417244.1. NC_000913.3.
WP_000211913.1. NZ_LN832404.1.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1DDGX-ray2.01A/B226-599[»]
1DDIX-ray2.51A226-599[»]
1YKGNMR-A53-219[»]
DisProtiDP00190.
ProteinModelPortaliP38038.
SMRiP38038. Positions 64-599.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi4262283. 213 interactions.
DIPiDIP-9381N.
IntActiP38038. 3 interactions.
MINTiMINT-1239442.
STRINGi511145.b2764.

Chemistry

DrugBankiDB03147. Flavin adenine dinucleotide.

Proteomic databases

EPDiP38038.
PaxDbiP38038.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblBacteriaiAAC75806; AAC75806; b2764.
BAE76841; BAE76841; BAE76841.
GeneIDi947239.
KEGGiecj:JW2734.
eco:b2764.
PATRICi32120940. VBIEscCol129921_2862.

Organism-specific databases

EchoBASEiEB0188.
EcoGeneiEG10191. cysJ.

Phylogenomic databases

eggNOGiENOG4107EER. Bacteria.
COG0369. LUCA.
HOGENOMiHOG000282025.
InParanoidiP38038.
KOiK00380.
OMAiGVWYEND.
OrthoDBiEOG6CVV7G.
PhylomeDBiP38038.

Enzyme and pathway databases

UniPathwayiUPA00140; UER00207.
BioCyciEcoCyc:ALPHACOMP-MONOMER.
ECOL316407:JW2734-MONOMER.
MetaCyc:ALPHACOMP-MONOMER.
BRENDAi1.8.1.2. 2026.

Miscellaneous databases

EvolutionaryTraceiP38038.
PROiP38038.

Family and domain databases

Gene3Di1.20.990.10. 1 hit.
3.40.50.360. 1 hit.
HAMAPiMF_01541. CysJ.
InterProiIPR010199. CysJ.
IPR029758. CysJ_Proteobact.
IPR003097. FAD-binding_1.
IPR017927. Fd_Rdtase_FAD-bd.
IPR001094. Flavdoxin-like.
IPR008254. Flavodoxin/NO_synth.
IPR001709. Flavoprot_Pyr_Nucl_cyt_Rdtase.
IPR029039. Flavoprotein-like_dom.
IPR023173. NADPH_Cyt_P450_Rdtase_dom3.
IPR001433. OxRdtase_FAD/NAD-bd.
IPR017938. Riboflavin_synthase-like_b-brl.
[Graphical view]
PfamiPF00667. FAD_binding_1. 1 hit.
PF00258. Flavodoxin_1. 1 hit.
PF00175. NAD_binding_1. 1 hit.
[Graphical view]
PIRSFiPIRSF000207. SiR-FP_CysJ. 1 hit.
PRINTSiPR00369. FLAVODOXIN.
PR00371. FPNCR.
SUPFAMiSSF52218. SSF52218. 1 hit.
SSF63380. SSF63380. 1 hit.
TIGRFAMsiTIGR01931. cysJ. 1 hit.
PROSITEiPS51384. FAD_FR. 1 hit.
PS50902. FLAVODOXIN_LIKE. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Characterization of the flavoprotein moieties of NADPH-sulfite reductase from Salmonella typhimurium and Escherichia coli. Physicochemical and catalytic properties, amino acid sequence deduced from DNA sequence of cysJ, and comparison with NADPH-cytochrome P-450 reductase."
    Ostrowski J., Barber M.J., Rueger D.C., Miller B.E., Siegel L.M., Kredich N.M.
    J. Biol. Chem. 264:15796-15808(1989) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    Strain: B.
  2. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: K12 / MG1655 / ATCC 47076.
  3. "Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110."
    Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T.
    Mol. Syst. Biol. 2:E1-E5(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
  4. "Characterization of the cysJIH regions of Salmonella typhimurium and Escherichia coli B. DNA sequences of cysI and cysH and a model for the siroheme-Fe4S4 active center of sulfite reductase hemoprotein based on amino acid homology with spinach nitrite reductase."
    Ostrowski J., Wu J.-Y., Rueger D.C., Miller B.E., Siegel L.M., Kredich N.M.
    J. Biol. Chem. 264:15726-15737(1989) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 594-599.
    Strain: B.
  5. "NADPH-sulfite reductase flavoprotein from Escherichia coli: contribution to the flavin content and subunit interaction."
    Eschenbrenner M., Coves J., Fontecave M.
    FEBS Lett. 374:82-84(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION OF FAD AND FMN DOMAINS.
  6. "The flavin reductase activity of the flavoprotein component of sulfite reductase from Escherichia coli. A new model for the protein structure."
    Eschenbrenner M., Coves J., Fontecave M.
    J. Biol. Chem. 270:20550-20555(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION AS A NADPH:FLAVIN OXIDOREDUCTASE.
  7. "Flavin mononucleotide-binding domain of the flavoprotein component of the sulfite reductase from Escherichia coli."
    Coves J., Zeghouf M., Macherel D., Guigliarelli B., Asso M., Fontecave M.
    Biochemistry 36:5921-5928(1997) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION OF FMN DOMAIN 1-220.
  8. "The flavoprotein component of the Escherichia coli sulfite reductase can act as a cytochrome P450c17 reductase."
    Zeghouf M., Defaye G., Fontecave M., Coves J.
    Biochem. Biophys. Res. Commun. 246:602-605(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION AS A NADPH-CYTOCHROME P450 REDUCTASE.
  9. "The flavoprotein component of the Escherichia coli sulfite reductase: expression, purification, and spectral and catalytic properties of a monomeric form containing both the flavin adenine dinucleotide and the flavin mononucleotide cofactors."
    Zeghouf M., Fontecave M., Macherel D., Coves J.
    Biochemistry 37:6114-6123(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION.
  10. "Overexpression of the FAD-binding domain of the sulphite reductase flavoprotein component from Escherichia coli and its inhibition by iodonium diphenyl chloride."
    Coves J., Lebrun C., Gervasi G., Dalbon P., Fontecave M.
    Biochem. J. 342:465-472(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION OF FAD DOMAIN.
  11. "Reactivity, secondary structure, and molecular topology of the Escherichia coli sulfite reductase flavodoxin-like domain."
    Champier L., Sibille N., Bersch B., Brutscher B., Blackledge M., Coves J.
    Biochemistry 41:3770-3780(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION, STRUCTURE BY NMR OF 53-220.
  12. "A simplifed functional version of the Escherichia coli sulfite reductase."
    Zeghouf M., Fontecave M., Coves J.
    J. Biol. Chem. 275:37651-37656(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: QUATERNARY STRUCTURE.
  13. "Four crystal structures of the 60 kDa flavoprotein monomer of the sulfite reductase indicate a disordered flavodoxin-like module."
    Gruez A., Pignol D., Zeghouf M., Coves J., Fontecave M., Ferrer J.-L., Fontecilla-Camps J.-C.
    J. Mol. Biol. 299:199-212(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.01 ANGSTROMS) OF 226-599 IN COMPLEXES WITH FAD AND NADP, COFACTOR, IDENTIFICATION BY MASS SPECTROMETRY, PARTIAL PROTEIN SEQUENCE, CATALYTIC ACTIVITY.
  14. "Solution structure of the sulfite reductase flavodoxin-like domain from Escherichia coli."
    Sibille N., Blackledge M., Brutscher B., Coves J., Bersch B.
    Biochemistry 44:9086-9095(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: STRUCTURE BY NMR OF 53-218 IN COMPLEX WITH FMN.

Entry informationi

Entry nameiCYSJ_ECOLI
AccessioniPrimary (citable) accession number: P38038
Secondary accession number(s): P14782, Q2MA65
Entry historyi
Integrated into UniProtKB/Swiss-Prot: October 1, 1994
Last sequence update: January 23, 2007
Last modified: July 6, 2016
This is version 153 of the entry and version 4 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Escherichia coli
    Escherichia coli (strain K12): entries and cross-references to EcoGene
  2. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  3. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  4. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.