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Protein

Glutathione reductase, mitochondrial

Gene

GSR

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Maintains high levels of reduced glutathione in the cytosol.

Catalytic activityi

2 glutathione + NADP+ = glutathione disulfide + NADPH.

Cofactori

FADNote: Binds 1 FAD per subunit.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Active sitei511Proton acceptor1

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Nucleotide bindingi94 – 102FAD9

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Oxidoreductase

Keywords - Ligandi

FAD, Flavoprotein, NADP

Enzyme and pathway databases

BioCyciMetaCyc:HS02602-MONOMER.
ZFISH:HS02602-MONOMER.
BRENDAi1.8.1.7. 2681.
ReactomeiR-HSA-2408550. Metabolism of ingested H2SeO4 and H2SeO3 into H2Se.
R-HSA-3299685. Detoxification of Reactive Oxygen Species.
R-HSA-499943. Synthesis and interconversion of nucleotide di- and triphosphates.
R-HSA-5628897. TP53 Regulates Metabolic Genes.
SABIO-RKP00390.

Names & Taxonomyi

Protein namesi
Recommended name:
Glutathione reductase, mitochondrial (EC:1.8.1.7)
Short name:
GR
Short name:
GRase
Gene namesi
Name:GSR
Synonyms:GLUR, GRD1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 8

Organism-specific databases

HGNCiHGNC:4623. GSR.

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Mitochondrion

Pathology & Biotechi

Organism-specific databases

DisGeNETi2936.
MalaCardsiGSR.
MIMi138300. gene+phenotype.
OpenTargetsiENSG00000104687.
Orphaneti90030. Hemolytic anemia due to glutathione reductase deficiency.
PharmGKBiPA29014.

Chemistry databases

ChEMBLiCHEMBL2755.
DrugBankiDB00262. Carmustine.
DB03147. Flavin adenine dinucleotide.
DB00143. Glutathione.

Polymorphism and mutation databases

BioMutaiGSR.
DMDMi14916998.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Transit peptidei1 – 43MitochondrionSequence analysisAdd BLAST43
ChainiPRO_000003027644 – 522Glutathione reductase, mitochondrialAdd BLAST479

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei97N6-acetyllysineBy similarity1
Disulfide bondi102 ↔ 107Redox-active1 Publication
Disulfide bondi134Interchain1 Publication

Keywords - PTMi

Acetylation, Disulfide bond

Proteomic databases

EPDiP00390.
PaxDbiP00390.
PeptideAtlasiP00390.
PRIDEiP00390.

2D gel databases

REPRODUCTION-2DPAGEIPI00759575.

PTM databases

iPTMnetiP00390.
PhosphoSitePlusiP00390.

Expressioni

Gene expression databases

BgeeiENSG00000104687.
CleanExiHS_GSR.
ExpressionAtlasiP00390. baseline and differential.
GenevisibleiP00390. HS.

Organism-specific databases

HPAiCAB008632.
HPA001538.

Interactioni

Subunit structurei

Homodimer; disulfide-linked.1 Publication

Protein-protein interaction databases

BioGridi109191. 31 interactors.
IntActiP00390. 5 interactors.
MINTiMINT-5000460.
STRINGi9606.ENSP00000221130.

Chemistry databases

BindingDBiP00390.

Structurei

Secondary structure

1522
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi62 – 64Combined sources3
Beta strandi66 – 70Combined sources5
Helixi74 – 85Combined sources12
Beta strandi90 – 96Combined sources7
Helixi100 – 105Combined sources6
Helixi107 – 123Combined sources17
Turni124 – 130Combined sources7
Helixi140 – 164Combined sources25
Beta strandi168 – 172Combined sources5
Beta strandi174 – 176Combined sources3
Beta strandi183 – 186Combined sources4
Beta strandi189 – 192Combined sources4
Beta strandi196 – 198Combined sources3
Beta strandi202 – 204Combined sources3
Turni209 – 211Combined sources3
Helixi215 – 217Combined sources3
Helixi221 – 224Combined sources4
Beta strandi232 – 237Combined sources6
Helixi241 – 252Combined sources12
Beta strandi256 – 260Combined sources5
Beta strandi262 – 266Combined sources5
Helixi272 – 284Combined sources13
Beta strandi288 – 290Combined sources3
Beta strandi293 – 300Combined sources8
Beta strandi302 – 311Combined sources10
Beta strandi319 – 331Combined sources13
Beta strandi335 – 338Combined sources4
Turni340 – 343Combined sources4
Helixi344 – 347Combined sources4
Beta strandi370 – 372Combined sources3
Helixi374 – 377Combined sources4
Helixi383 – 398Combined sources16
Beta strandi413 – 415Combined sources3
Beta strandi417 – 419Combined sources3
Beta strandi421 – 425Combined sources5
Helixi428 – 435Combined sources8
Helixi437 – 439Combined sources3
Beta strandi440 – 447Combined sources8
Helixi450 – 454Combined sources5
Beta strandi461 – 468Combined sources8
Turni469 – 472Combined sources4
Beta strandi473 – 481Combined sources9
Helixi484 – 496Combined sources13
Helixi501 – 505Combined sources5
Beta strandi511 – 514Combined sources4
Helixi515 – 519Combined sources5

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1ALGNMR-A480-503[»]
1BWCX-ray2.10A45-522[»]
1DNCX-ray1.70A45-522[»]
1GRAX-ray2.00A45-522[»]
1GRBX-ray1.85A45-522[»]
1GREX-ray2.00A45-522[»]
1GRFX-ray2.00A45-522[»]
1GRGX-ray2.00A45-522[»]
1GRHX-ray3.00A45-522[»]
1GRTX-ray2.30A45-522[»]
1GSNX-ray1.70A45-522[»]
1K4QX-ray1.90A62-522[»]
1XANX-ray2.00A62-522[»]
2AAQX-ray2.60A44-522[»]
2GH5X-ray1.70A/B45-522[»]
2GRTX-ray2.70A62-522[»]
3DJGX-ray1.80X59-522[»]
3DJJX-ray1.10A45-522[»]
3DK4X-ray1.20A45-522[»]
3DK8X-ray1.10A45-522[»]
3DK9X-ray0.95A45-522[»]
3GRSX-ray1.54A45-522[»]
3GRTX-ray2.50A62-522[»]
3SQPX-ray2.21A/B45-522[»]
4GR1X-ray2.40A45-522[»]
4GRTX-ray2.80A62-522[»]
5GRTX-ray2.40A62-522[»]
ProteinModelPortaliP00390.
SMRiP00390.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP00390.

Family & Domainsi

Domaini

Each subunit can be divided into 4 domains that are consecutive along the polypeptide chain. Domains 1 and 2 bind FAD and NADPH, respectively. Domain 4 forms the interface.

Sequence similaritiesi

Keywords - Domaini

Redox-active center, Transit peptide

Phylogenomic databases

eggNOGiKOG0405. Eukaryota.
COG1249. LUCA.
GeneTreeiENSGT00390000007578.
HOGENOMiHOG000276712.
HOVERGENiHBG004959.
InParanoidiP00390.
KOiK00383.
OMAiHLYAKDY.
OrthoDBiEOG091G078A.
PhylomeDBiP00390.
TreeFamiTF105353.

Family and domain databases

Gene3Di3.30.390.30. 1 hit.
3.50.50.60. 3 hits.
InterProiIPR023753. FAD/NAD-binding_dom.
IPR016156. FAD/NAD-linked_Rdtase_dimer.
IPR006322. Glutathione_Rdtase_euk/bac.
IPR004099. Pyr_nucl-diS_OxRdtase_dimer.
IPR012999. Pyr_OxRdtase_I_AS.
[Graphical view]
PfamiPF07992. Pyr_redox_2. 1 hit.
PF02852. Pyr_redox_dim. 1 hit.
[Graphical view]
SUPFAMiSSF51905. SSF51905. 2 hits.
SSF55424. SSF55424. 1 hit.
TIGRFAMsiTIGR01421. gluta_reduc_1. 1 hit.
PROSITEiPS00076. PYRIDINE_REDOX_1. 1 hit.
[Graphical view]

Sequences (5)i

Sequence statusi: Complete.

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

This entry describes 5 isoformsi produced by alternative splicing and alternative initiation. AlignAdd to basket

Isoform Mitochondrial (identifier: P00390-1) [UniParc]FASTAAdd to basket

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

« Hide

        10         20         30         40         50
MALLPRALSA GAGPSWRRAA RAFRGFLLLL PEPAALTRAL SRAMACRQEP
60 70 80 90 100
QPQGPPPAAG AVASYDYLVI GGGSGGLASA RRAAELGARA AVVESHKLGG
110 120 130 140 150
TCVNVGCVPK KVMWNTAVHS EFMHDHADYG FPSCEGKFNW RVIKEKRDAY
160 170 180 190 200
VSRLNAIYQN NLTKSHIEII RGHAAFTSDP KPTIEVSGKK YTAPHILIAT
210 220 230 240 250
GGMPSTPHES QIPGASLGIT SDGFFQLEEL PGRSVIVGAG YIAVEMAGIL
260 270 280 290 300
SALGSKTSLM IRHDKVLRSF DSMISTNCTE ELENAGVEVL KFSQVKEVKK
310 320 330 340 350
TLSGLEVSMV TAVPGRLPVM TMIPDVDCLL WAIGRVPNTK DLSLNKLGIQ
360 370 380 390 400
TDDKGHIIVD EFQNTNVKGI YAVGDVCGKA LLTPVAIAAG RKLAHRLFEY
410 420 430 440 450
KEDSKLDYNN IPTVVFSHPP IGTVGLTEDE AIHKYGIENV KTYSTSFTPM
460 470 480 490 500
YHAVTKRKTK CVMKMVCANK EEKVVGIHMQ GLGCDEMLQG FAVAVKMGAT
510 520
KADFDNTVAI HPTSSEELVT LR
Length:522
Mass (Da):56,257
Last modified:July 11, 2001 - v2
Checksum:iDD8E2BA9D6E3757B
GO
Isoform Cytoplasmic (identifier: P00390-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-43: Missing.

Note: Produced by alternative initiation of isoform Mitochondrial.
Show »
Length:479
Mass (Da):51,701
Checksum:i3C0A194C96E880E7
GO
Isoform 2 (identifier: P00390-3) [UniParc]FASTAAdd to basket
Also known as: delta8

The sequence of this isoform differs from the canonical sequence as follows:
     266-294: Missing.

Show »
Length:493
Mass (Da):53,027
Checksum:iEFBA71DCDCFF1529
GO
Isoform 3 (identifier: P00390-4) [UniParc]FASTAAdd to basket
Also known as: delta9

The sequence of this isoform differs from the canonical sequence as follows:
     295-347: Missing.

Note: Expressed at very high levels in peripheral blood.
Show »
Length:469
Mass (Da):50,497
Checksum:i0AD475B02A87C63E
GO
Isoform 4 (identifier: P00390-5) [UniParc]FASTAAdd to basket
Also known as: delta8+9

The sequence of this isoform differs from the canonical sequence as follows:
     266-294: Missing.
     295-347: Missing.

Show »
Length:440
Mass (Da):47,267
Checksum:i793E0A9F8706B1B5
GO

Sequence cautioni

The sequence AAP88037 differs from that shown. Reason: Erroneous initiation.Curated

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_019079153R → C.1 PublicationCorresponds to variant rs8190955dbSNPEnsembl.1
Natural variantiVAR_051775232G → R.Corresponds to variant rs8190976dbSNPEnsembl.1
Natural variantiVAR_019080232G → S.1 PublicationCorresponds to variant rs8190976dbSNPEnsembl.1
Natural variantiVAR_019081261I → V.1 PublicationCorresponds to variant rs8190997dbSNPEnsembl.1
Natural variantiVAR_019082297E → D.1 PublicationCorresponds to variant rs8191004dbSNPEnsembl.1
Natural variantiVAR_014554314P → H.Corresponds to variant rs2020916dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0189721 – 43Missing in isoform Cytoplasmic. 1 PublicationAdd BLAST43
Alternative sequenceiVSP_042908266 – 294Missing in isoform 2 and isoform 4. 1 PublicationAdd BLAST29
Alternative sequenceiVSP_042909295 – 347Missing in isoform 3 and isoform 4. 1 PublicationAdd BLAST53

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X15722 mRNA. Translation: CAA33744.1.
AF228703 Genomic DNA. Translation: AAF37572.1.
AF228703 Genomic DNA. Translation: AAF37573.1.
AF228704 mRNA. Translation: AAF37574.1.
AY338490 Genomic DNA. Translation: AAP88037.1. Different initiation.
AB519179 mRNA. Translation: BAI43437.1.
AB519180 mRNA. Translation: BAI43438.1.
AB519181 mRNA. Translation: BAI43439.1.
AC009314 Genomic DNA. No translation available.
AC103959 Genomic DNA. No translation available.
AF215848 Genomic DNA. No translation available.
CH471080 Genomic DNA. Translation: EAW63443.1.
CH471080 Genomic DNA. Translation: EAW63445.1.
BC069244 mRNA. Translation: AAH69244.1.
CCDSiCCDS34877.1. [P00390-1]
CCDS56530.1. [P00390-5]
CCDS56531.1. [P00390-3]
CCDS56532.1. [P00390-4]
PIRiS08979. RDHUU.
RefSeqiNP_000628.2. NM_000637.3. [P00390-1]
NP_001182031.1. NM_001195102.1. [P00390-3]
NP_001182032.1. NM_001195103.1. [P00390-4]
NP_001182033.1. NM_001195104.1. [P00390-5]
UniGeneiHs.271510.

Genome annotation databases

EnsembliENST00000221130; ENSP00000221130; ENSG00000104687. [P00390-1]
ENST00000537535; ENSP00000438845; ENSG00000104687. [P00390-5]
ENST00000541648; ENSP00000444559; ENSG00000104687. [P00390-4]
ENST00000546342; ENSP00000445516; ENSG00000104687. [P00390-3]
GeneIDi2936.
KEGGihsa:2936.
UCSCiuc022ato.2. human. [P00390-1]

Keywords - Coding sequence diversityi

Alternative initiation, Alternative splicing, Polymorphism

Cross-referencesi

Web resourcesi

NIEHS-SNPs
Wikipedia

Glutathione reductase entry

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X15722 mRNA. Translation: CAA33744.1.
AF228703 Genomic DNA. Translation: AAF37572.1.
AF228703 Genomic DNA. Translation: AAF37573.1.
AF228704 mRNA. Translation: AAF37574.1.
AY338490 Genomic DNA. Translation: AAP88037.1. Different initiation.
AB519179 mRNA. Translation: BAI43437.1.
AB519180 mRNA. Translation: BAI43438.1.
AB519181 mRNA. Translation: BAI43439.1.
AC009314 Genomic DNA. No translation available.
AC103959 Genomic DNA. No translation available.
AF215848 Genomic DNA. No translation available.
CH471080 Genomic DNA. Translation: EAW63443.1.
CH471080 Genomic DNA. Translation: EAW63445.1.
BC069244 mRNA. Translation: AAH69244.1.
CCDSiCCDS34877.1. [P00390-1]
CCDS56530.1. [P00390-5]
CCDS56531.1. [P00390-3]
CCDS56532.1. [P00390-4]
PIRiS08979. RDHUU.
RefSeqiNP_000628.2. NM_000637.3. [P00390-1]
NP_001182031.1. NM_001195102.1. [P00390-3]
NP_001182032.1. NM_001195103.1. [P00390-4]
NP_001182033.1. NM_001195104.1. [P00390-5]
UniGeneiHs.271510.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1ALGNMR-A480-503[»]
1BWCX-ray2.10A45-522[»]
1DNCX-ray1.70A45-522[»]
1GRAX-ray2.00A45-522[»]
1GRBX-ray1.85A45-522[»]
1GREX-ray2.00A45-522[»]
1GRFX-ray2.00A45-522[»]
1GRGX-ray2.00A45-522[»]
1GRHX-ray3.00A45-522[»]
1GRTX-ray2.30A45-522[»]
1GSNX-ray1.70A45-522[»]
1K4QX-ray1.90A62-522[»]
1XANX-ray2.00A62-522[»]
2AAQX-ray2.60A44-522[»]
2GH5X-ray1.70A/B45-522[»]
2GRTX-ray2.70A62-522[»]
3DJGX-ray1.80X59-522[»]
3DJJX-ray1.10A45-522[»]
3DK4X-ray1.20A45-522[»]
3DK8X-ray1.10A45-522[»]
3DK9X-ray0.95A45-522[»]
3GRSX-ray1.54A45-522[»]
3GRTX-ray2.50A62-522[»]
3SQPX-ray2.21A/B45-522[»]
4GR1X-ray2.40A45-522[»]
4GRTX-ray2.80A62-522[»]
5GRTX-ray2.40A62-522[»]
ProteinModelPortaliP00390.
SMRiP00390.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi109191. 31 interactors.
IntActiP00390. 5 interactors.
MINTiMINT-5000460.
STRINGi9606.ENSP00000221130.

Chemistry databases

BindingDBiP00390.
ChEMBLiCHEMBL2755.
DrugBankiDB00262. Carmustine.
DB03147. Flavin adenine dinucleotide.
DB00143. Glutathione.

PTM databases

iPTMnetiP00390.
PhosphoSitePlusiP00390.

Polymorphism and mutation databases

BioMutaiGSR.
DMDMi14916998.

2D gel databases

REPRODUCTION-2DPAGEIPI00759575.

Proteomic databases

EPDiP00390.
PaxDbiP00390.
PeptideAtlasiP00390.
PRIDEiP00390.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000221130; ENSP00000221130; ENSG00000104687. [P00390-1]
ENST00000537535; ENSP00000438845; ENSG00000104687. [P00390-5]
ENST00000541648; ENSP00000444559; ENSG00000104687. [P00390-4]
ENST00000546342; ENSP00000445516; ENSG00000104687. [P00390-3]
GeneIDi2936.
KEGGihsa:2936.
UCSCiuc022ato.2. human. [P00390-1]

Organism-specific databases

CTDi2936.
DisGeNETi2936.
GeneCardsiGSR.
HGNCiHGNC:4623. GSR.
HPAiCAB008632.
HPA001538.
MalaCardsiGSR.
MIMi138300. gene+phenotype.
neXtProtiNX_P00390.
OpenTargetsiENSG00000104687.
Orphaneti90030. Hemolytic anemia due to glutathione reductase deficiency.
PharmGKBiPA29014.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG0405. Eukaryota.
COG1249. LUCA.
GeneTreeiENSGT00390000007578.
HOGENOMiHOG000276712.
HOVERGENiHBG004959.
InParanoidiP00390.
KOiK00383.
OMAiHLYAKDY.
OrthoDBiEOG091G078A.
PhylomeDBiP00390.
TreeFamiTF105353.

Enzyme and pathway databases

BioCyciMetaCyc:HS02602-MONOMER.
ZFISH:HS02602-MONOMER.
BRENDAi1.8.1.7. 2681.
ReactomeiR-HSA-2408550. Metabolism of ingested H2SeO4 and H2SeO3 into H2Se.
R-HSA-3299685. Detoxification of Reactive Oxygen Species.
R-HSA-499943. Synthesis and interconversion of nucleotide di- and triphosphates.
R-HSA-5628897. TP53 Regulates Metabolic Genes.
SABIO-RKP00390.

Miscellaneous databases

EvolutionaryTraceiP00390.
GeneWikiiGlutathione_reductase.
GenomeRNAii2936.
PROiP00390.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000104687.
CleanExiHS_GSR.
ExpressionAtlasiP00390. baseline and differential.
GenevisibleiP00390. HS.

Family and domain databases

Gene3Di3.30.390.30. 1 hit.
3.50.50.60. 3 hits.
InterProiIPR023753. FAD/NAD-binding_dom.
IPR016156. FAD/NAD-linked_Rdtase_dimer.
IPR006322. Glutathione_Rdtase_euk/bac.
IPR004099. Pyr_nucl-diS_OxRdtase_dimer.
IPR012999. Pyr_OxRdtase_I_AS.
[Graphical view]
PfamiPF07992. Pyr_redox_2. 1 hit.
PF02852. Pyr_redox_dim. 1 hit.
[Graphical view]
SUPFAMiSSF51905. SSF51905. 2 hits.
SSF55424. SSF55424. 1 hit.
TIGRFAMsiTIGR01421. gluta_reduc_1. 1 hit.
PROSITEiPS00076. PYRIDINE_REDOX_1. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiGSHR_HUMAN
AccessioniPrimary (citable) accession number: P00390
Secondary accession number(s): C8KIL8
, C8KIL9, C8KIM0, D3DSV3, Q7Z5C9, Q9NP63
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 11, 2001
Last modified: November 2, 2016
This is version 218 of the entry and version 2 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Miscellaneous

The active site is a redox-active disulfide bond.

Keywords - Technical termi

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

Documents

  1. Human chromosome 8
    Human chromosome 8: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  6. 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.