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Protein

Adenylyltransferase and sulfurtransferase MOCS3

Gene

MOCS3

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

Functioni

Plays a central role in 2-thiolation of mcm5S2U at tRNA wobble positions of cytosolic tRNA(Lys), tRNA(Glu) and tRNA(Gln). Also essential during biosynthesis of the molybdenum cofactor. Acts by mediating the C-terminal thiocarboxylation of sulfur carriers URM1 and MOCS2A. Its N-terminus first activates URM1 and MOCS2A as acyl-adenylates (-COAMP), then the persulfide sulfur on the catalytic cysteine is transferred to URM1 and MOCS2A to form thiocarboxylation (-COSH) of their C-terminus. The reaction probably involves hydrogen sulfide that is generated from the persulfide intermediate and that acts as nucleophile towards URM1 and MOCS2A. Subsequently, a transient disulfide bond is formed. Does not use thiosulfate as sulfur donor; NFS1 probably acting as a sulfur donor for thiocarboxylation reactions.2 PublicationsUniRule annotation

Catalytic activityi

ATP + [molybdopterin-synthase sulfur-carrier protein]-Gly-Gly = diphosphate + [molybdopterin-synthase sulfur-carrier protein]-Gly-Gly-AMP.UniRule annotation
[Molybdopterin-synthase sulfur-carrier protein]-Gly-Gly-AMP + [cysteine desulfurase]-S-sulfanyl-L-cysteine = AMP + [molybdopterin-synthase sulfur-carrier protein]-Gly-NH-CH(2)-C(O)SH + cysteine desulfurase.UniRule annotation

Cofactori

Zn2+UniRule annotationNote: Binds 1 zinc ion per subunit.UniRule annotation

Kineticsi

  1. KM=0.25 mM for thiosulfate1 Publication
  2. KM=0.28 mM for cyanide1 Publication

Pathwayi

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Binding sitei92 – 921ATP; via amide nitrogenUniRule annotation
Binding sitei113 – 1131ATPUniRule annotation
Binding sitei137 – 1371ATPUniRule annotation
Metal bindingi222 – 2221ZincUniRule annotation
Metal bindingi225 – 2251ZincUniRule annotation
Active sitei239 – 2391Glycyl thioester intermediate; for adenylyltransferase activityUniRule annotation
Metal bindingi297 – 2971ZincUniRule annotation
Metal bindingi300 – 3001ZincUniRule annotation
Active sitei412 – 4121Cysteine persulfide intermediate; for sulfurtransferase activity1 PublicationUniRule annotation

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi120 – 1245ATPUniRule annotation
Nucleotide bindingi181 – 1822ATPUniRule annotation

GO - Molecular functioni

  1. ATP binding Source: UniProtKB-KW
  2. metal ion binding Source: UniProtKB-KW
  3. molybdopterin-synthase adenylyltransferase activity Source: UniProtKB-EC
  4. molybdopterin-synthase sulfurtransferase activity Source: UniProtKB-EC
  5. nucleotidyltransferase activity Source: UniProtKB
  6. protein adenylyltransferase activity Source: GO_Central
  7. sulfurtransferase activity Source: UniProtKB
  8. thiosulfate sulfurtransferase activity Source: UniProtKB
  9. URM1 activating enzyme activity Source: UniProtKB

GO - Biological processi

  1. enzyme active site formation via L-cysteine persulfide Source: UniProtKB
  2. molybdopterin cofactor biosynthetic process Source: Reactome
  3. Mo-molybdopterin cofactor biosynthetic process Source: UniProtKB
  4. protein adenylylation Source: GOC
  5. protein urmylation Source: GO_Central
  6. small molecule metabolic process Source: Reactome
  7. tRNA thio-modification Source: UniProtKB
  8. tRNA wobble position uridine thiolation Source: GO_Central
  9. tRNA wobble uridine modification Source: UniProtKB
  10. vitamin metabolic process Source: Reactome
  11. water-soluble vitamin metabolic process Source: Reactome
Complete GO annotation...

Keywords - Molecular functioni

Transferase

Keywords - Biological processi

Molybdenum cofactor biosynthesis, tRNA processing

Keywords - Ligandi

ATP-binding, Metal-binding, Nucleotide-binding, Zinc

Enzyme and pathway databases

BioCyciMetaCyc:HS04742-MONOMER.
ReactomeiREACT_25073. Molybdenum cofactor biosynthesis.
UniPathwayiUPA00344.
UPA00988.

Names & Taxonomyi

Protein namesi
Recommended name:
Adenylyltransferase and sulfurtransferase MOCS3UniRule annotation
Alternative name(s):
Molybdenum cofactor synthesis protein 3UniRule annotation
Molybdopterin synthase sulfurylase
Short name:
MPT synthase sulfurylase
Including the following 2 domains:
Molybdopterin-synthase adenylyltransferaseUniRule annotation (EC:2.7.7.80UniRule annotation)
Alternative name(s):
Adenylyltransferase MOCS3UniRule annotation
Sulfur carrier protein MOCS2A adenylyltransferaseUniRule annotation
Molybdopterin-synthase sulfurtransferaseUniRule annotation (EC:2.8.1.11UniRule annotation)
Alternative name(s):
Sulfur carrier protein MOCS2A sulfurtransferaseUniRule annotation
Sulfurtransferase MOCS3UniRule annotation
Gene namesi
Name:MOCS3UniRule annotation
Synonyms:UBA4UniRule annotation
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640: Chromosome 20

Organism-specific databases

HGNCiHGNC:15765. MOCS3.

Subcellular locationi

Cytoplasm 1 PublicationUniRule annotation

GO - Cellular componenti

  1. cytosol Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi239 – 2391C → A: Impairs sulfurtransferase activity. 1 Publication
Mutagenesisi316 – 3161C → A: Does not affect sulfurtransferase activity. 1 Publication
Mutagenesisi324 – 3241C → A: Does not affect sulfurtransferase activity. 1 Publication
Mutagenesisi365 – 3651C → A: Does not affect sulfurtransferase activity. 1 Publication
Mutagenesisi412 – 4121C → A: Abolishes sulfurtransferase activity. 1 Publication
Mutagenesisi413 – 4131K → R: Does not affect sulfurtransferase specificity and activity. 1 Publication
Mutagenesisi414 – 4141L → K: Does not affect sulfurtransferase specificity and activity. 1 Publication
Mutagenesisi415 – 4151G → A: Does not affect sulfurtransferase specificity and activity. 1 Publication
Mutagenesisi416 – 4161N → V: Does not affect sulfurtransferase specificity and activity. 1 Publication
Mutagenesisi417 – 4171D → R: Results in 470-fold increased activity. 1 Publication
Mutagenesisi417 – 4171D → T: Results in 90-fold increased activity. 1 Publication
Mutagenesisi458 – 4581P → G: Does not affect sulfurtransferase specificity and activity. 1 Publication
Mutagenesisi460 – 4601Y → A: Does not affect sulfurtransferase specificity and activity. 1 Publication

Organism-specific databases

PharmGKBiPA30904.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 460460Adenylyltransferase and sulfurtransferase MOCS3PRO_0000120583Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi316 ↔ 3241 Publication

Keywords - PTMi

Disulfide bond

Proteomic databases

MaxQBiO95396.
PaxDbiO95396.
PeptideAtlasiO95396.
PRIDEiO95396.

PTM databases

PhosphoSiteiO95396.

Expressioni

Gene expression databases

BgeeiO95396.
CleanExiHS_MOCS3.
GenevestigatoriO95396.

Organism-specific databases

HPAiHPA027556.

Interactioni

Subunit structurei

Interacts with NFS1.1 PublicationUniRule annotation

Protein-protein interaction databases

BioGridi118127. 10 interactions.
DIPiDIP-31168N.
IntActiO95396. 1 interaction.
MINTiMINT-5003967.
STRINGi9606.ENSP00000244051.

Structurei

Secondary structure

1
460
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi338 – 34710Combined sources
Beta strandi352 – 3554Combined sources
Helixi359 – 3646Combined sources
Beta strandi370 – 3723Combined sources
Helixi375 – 3795Combined sources
Helixi383 – 39715Combined sources
Beta strandi406 – 4116Combined sources
Beta strandi413 – 4164Combined sources
Helixi417 – 43014Combined sources
Beta strandi433 – 4353Combined sources
Beta strandi437 – 4426Combined sources
Helixi445 – 4528Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
3I2VX-ray1.25A335-460[»]
ProteinModelPortaliO95396.
SMRiO95396. Positions 5-301, 335-460.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiO95396.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini347 – 458112RhodaneseUniRule annotationAdd
BLAST

Sequence similaritiesi

In the N-terminal section; belongs to the HesA/MoeB/ThiF family. UBA4 subfamily.UniRule annotation
Contains 1 rhodanese domain.UniRule annotation

Phylogenomic databases

eggNOGiCOG0476.
GeneTreeiENSGT00570000079161.
HOGENOMiHOG000281219.
HOVERGENiHBG052491.
InParanoidiO95396.
KOiK11996.
OMAiSRRLDCA.
OrthoDBiEOG776SQ3.
PhylomeDBiO95396.
TreeFamiTF106103.

Family and domain databases

Gene3Di3.40.250.10. 1 hit.
3.40.50.720. 1 hit.
HAMAPiMF_03049. MOCS3_Uba4.
InterProiIPR028885. MOCS3/Uba4.
IPR007901. MoeZ_MoeB.
IPR009036. Molybdenum_cofac_synth_MoeB.
IPR016040. NAD(P)-bd_dom.
IPR001763. Rhodanese-like_dom.
IPR000594. ThiF_NAD_FAD-bd.
[Graphical view]
PfamiPF05237. MoeZ_MoeB. 1 hit.
PF00581. Rhodanese. 1 hit.
PF00899. ThiF. 1 hit.
[Graphical view]
SMARTiSM00450. RHOD. 1 hit.
[Graphical view]
SUPFAMiSSF69572. SSF69572. 1 hit.
PROSITEiPS50206. RHODANESE_3. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

O95396-1 [UniParc]FASTAAdd to Basket

« Hide

        10         20         30         40         50
MASREEVLAL QAEVAQREEE LNSLKQKLAS ALLAEQEPQP ERLVPVSPLP
60 70 80 90 100
PKAALSRDEI LRYSRQLVLP ELGVHGQLRL GTACVLIVGC GGLGCPLAQY
110 120 130 140 150
LAAAGVGRLG LVDYDVVEMS NLARQVLHGE ALAGQAKAFS AAASLRRLNS
160 170 180 190 200
AVECVPYTQA LTPATALDLV RRYDVVADCS DNVPTRYLVN DACVLAGRPL
210 220 230 240 250
VSASALRFEG QITVYHYDGG PCYRCIFPQP PPAETVTNCA DGGVLGVVTG
260 270 280 290 300
VLGCLQALEV LKIAAGLGPS YSGSLLLFDA LRGHFRSIRL RSRRLDCAAC
310 320 330 340 350
GERPTVTDLL DYEAFCGSSA TDKCRSLQLL SPEERVSVTD YKRLLDSGAF
360 370 380 390 400
HLLLDVRPQV EVDICRLPHA LHIPLKHLER RDAESLKLLK EAIWEEKQGT
410 420 430 440 450
QEGAAVPIYV ICKLGNDSQK AVKILQSLSA AQELDPLTVR DVVGGLMAWA
460
AKIDGTFPQY
Length:460
Mass (Da):49,669
Last modified:May 1, 1999 - v1
Checksum:i299A4E755173E324
GO

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti429 – 4291S → A.
Corresponds to variant rs7269297 [ dbSNP | Ensembl ].
VAR_049349

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF102544 mRNA. Translation: AAC72412.1.
AL034553 Genomic DNA. Translation: CAB53750.1.
BC015939 mRNA. Translation: AAH15939.1.
CCDSiCCDS13435.1.
RefSeqiNP_055299.1. NM_014484.4.
UniGeneiHs.159410.
Hs.736268.

Genome annotation databases

EnsembliENST00000244051; ENSP00000244051; ENSG00000124217.
GeneIDi27304.
KEGGihsa:27304.
UCSCiuc002xvy.2. human.

Keywords - Coding sequence diversityi

Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF102544 mRNA. Translation: AAC72412.1.
AL034553 Genomic DNA. Translation: CAB53750.1.
BC015939 mRNA. Translation: AAH15939.1.
CCDSiCCDS13435.1.
RefSeqiNP_055299.1. NM_014484.4.
UniGeneiHs.159410.
Hs.736268.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
3I2VX-ray1.25A335-460[»]
ProteinModelPortaliO95396.
SMRiO95396. Positions 5-301, 335-460.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi118127. 10 interactions.
DIPiDIP-31168N.
IntActiO95396. 1 interaction.
MINTiMINT-5003967.
STRINGi9606.ENSP00000244051.

PTM databases

PhosphoSiteiO95396.

Proteomic databases

MaxQBiO95396.
PaxDbiO95396.
PeptideAtlasiO95396.
PRIDEiO95396.

Protocols and materials databases

DNASUi27304.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000244051; ENSP00000244051; ENSG00000124217.
GeneIDi27304.
KEGGihsa:27304.
UCSCiuc002xvy.2. human.

Organism-specific databases

CTDi27304.
GeneCardsiGC20P049575.
HGNCiHGNC:15765. MOCS3.
HPAiHPA027556.
MIMi609277. gene.
neXtProtiNX_O95396.
PharmGKBiPA30904.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiCOG0476.
GeneTreeiENSGT00570000079161.
HOGENOMiHOG000281219.
HOVERGENiHBG052491.
InParanoidiO95396.
KOiK11996.
OMAiSRRLDCA.
OrthoDBiEOG776SQ3.
PhylomeDBiO95396.
TreeFamiTF106103.

Enzyme and pathway databases

UniPathwayiUPA00344.
UPA00988.
BioCyciMetaCyc:HS04742-MONOMER.
ReactomeiREACT_25073. Molybdenum cofactor biosynthesis.

Miscellaneous databases

EvolutionaryTraceiO95396.
GeneWikiiMOCS3.
GenomeRNAii27304.
NextBioi50301.
PROiO95396.
SOURCEiSearch...

Gene expression databases

BgeeiO95396.
CleanExiHS_MOCS3.
GenevestigatoriO95396.

Family and domain databases

Gene3Di3.40.250.10. 1 hit.
3.40.50.720. 1 hit.
HAMAPiMF_03049. MOCS3_Uba4.
InterProiIPR028885. MOCS3/Uba4.
IPR007901. MoeZ_MoeB.
IPR009036. Molybdenum_cofac_synth_MoeB.
IPR016040. NAD(P)-bd_dom.
IPR001763. Rhodanese-like_dom.
IPR000594. ThiF_NAD_FAD-bd.
[Graphical view]
PfamiPF05237. MoeZ_MoeB. 1 hit.
PF00581. Rhodanese. 1 hit.
PF00899. ThiF. 1 hit.
[Graphical view]
SMARTiSM00450. RHOD. 1 hit.
[Graphical view]
SUPFAMiSSF69572. SSF69572. 1 hit.
PROSITEiPS50206. RHODANESE_3. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Evidence for the physiological role of a rhodanese-like protein for the biosynthesis of the molybdenum cofactor in humans."
    Matthies A., Rajagopalan K.V., Mendel R.R., Leimkuehler S.
    Proc. Natl. Acad. Sci. U.S.A. 101:5946-5951(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION IN BIOSYNTHESIS OF THE MOLYBDENUM COFACTOR, BIOPHYSICOCHEMICAL PROPERTIES, SUBCELLULAR LOCATION, MUTAGENESIS OF CYS-239; CYS-316; CYS-324; CYS-365 AND CYS-412.
  2. "The DNA sequence and comparative analysis of human chromosome 20."
    Deloukas P., Matthews L.H., Ashurst J.L., Burton J., Gilbert J.G.R., Jones M., Stavrides G., Almeida J.P., Babbage A.K., Bagguley C.L., Bailey J., Barlow K.F., Bates K.N., Beard L.M., Beare D.M., Beasley O.P., Bird C.P., Blakey S.E.
    , Bridgeman A.M., Brown A.J., Buck D., Burrill W.D., Butler A.P., Carder C., Carter N.P., Chapman J.C., Clamp M., Clark G., Clark L.N., Clark S.Y., Clee C.M., Clegg S., Cobley V.E., Collier R.E., Connor R.E., Corby N.R., Coulson A., Coville G.J., Deadman R., Dhami P.D., Dunn M., Ellington A.G., Frankland J.A., Fraser A., French L., Garner P., Grafham D.V., Griffiths C., Griffiths M.N.D., Gwilliam R., Hall R.E., Hammond S., Harley J.L., Heath P.D., Ho S., Holden J.L., Howden P.J., Huckle E., Hunt A.R., Hunt S.E., Jekosch K., Johnson C.M., Johnson D., Kay M.P., Kimberley A.M., King A., Knights A., Laird G.K., Lawlor S., Lehvaeslaiho M.H., Leversha M.A., Lloyd C., Lloyd D.M., Lovell J.D., Marsh V.L., Martin S.L., McConnachie L.J., McLay K., McMurray A.A., Milne S.A., Mistry D., Moore M.J.F., Mullikin J.C., Nickerson T., Oliver K., Parker A., Patel R., Pearce T.A.V., Peck A.I., Phillimore B.J.C.T., Prathalingam S.R., Plumb R.W., Ramsay H., Rice C.M., Ross M.T., Scott C.E., Sehra H.K., Shownkeen R., Sims S., Skuce C.D., Smith M.L., Soderlund C., Steward C.A., Sulston J.E., Swann R.M., Sycamore N., Taylor R., Tee L., Thomas D.W., Thorpe A., Tracey A., Tromans A.C., Vaudin M., Wall M., Wallis J.M., Whitehead S.L., Whittaker P., Willey D.L., Williams L., Williams S.A., Wilming L., Wray P.W., Hubbard T., Durbin R.M., Bentley D.R., Beck S., Rogers J.
    Nature 414:865-871(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  3. "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
    The MGC Project Team
    Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Tissue: Uterus.
  4. "Molybdenum cofactor biosynthesis in humans: identification of a persulfide group in the rhodanese-like domain of MOCS3 by mass spectrometry."
    Matthies A., Nimtz M., Leimkuehler S.
    Biochemistry 44:7912-7920(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACTIVE SITE, DISULFIDE BOND.
  5. "Site-directed mutagenesis of the active site loop of the rhodanese-like domain of the human molybdopterin synthase sulfurase MOCS3. Major differences in substrate specificity between eukaryotic and bacterial homologs."
    Krepinsky K., Leimkuehler S.
    FEBS J. 274:2778-2787(2007) [PubMed] [Europe PMC] [Abstract]
    Cited for: ENZYME ACTIVITY, MUTAGENESIS OF LYS-413; LEU-414; GLY-415; ASN-416; ASP-417; PRO-458 AND TYR-460.
  6. "A novel role for human Nfs1 in the cytoplasm: Nfs1 acts as a sulfur donor for MOCS3, a protein involved in molybdenum cofactor biosynthesis."
    Marelja Z., Stoecklein W., Nimtz M., Leimkuehler S.
    J. Biol. Chem. 283:25178-25185(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: ENZYME ACTIVITY, INTERACTION WITH NFS1.
  7. "A functional proteomics approach links the ubiquitin-related modifier Urm1 to a tRNA modification pathway."
    Schlieker C.D., Van der Veen A.G., Damon J.R., Spooner E., Ploegh H.L.
    Proc. Natl. Acad. Sci. U.S.A. 105:18255-18260(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION IN 2-THIOLATION OF TRNA.
  8. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  9. "Crystal structure of the human MOCS3 rhodanese-like domain."
    Structural genomics consortium (SGC)
    Submitted (JUL-2009) to the PDB data bank
    Cited for: X-RAY CRYSTALLOGRAPHY (1.25 ANGSTROMS) OF 335-460.

Entry informationi

Entry nameiMOCS3_HUMAN
AccessioniPrimary (citable) accession number: O95396
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 26, 2002
Last sequence update: May 1, 1999
Last modified: February 4, 2015
This is version 133 of the entry and version 1 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

Keywords - Technical termi

3D-structure, Complete proteome, Multifunctional enzyme, Reference proteome

Documents

  1. Human chromosome 20
    Human chromosome 20: 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. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  6. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  7. SIMILARITY comments
    Index of protein domains and families

External Data

Dasty 3

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 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.