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Protein

Pyrroline-5-carboxylate reductase 2

Gene

PYCR2

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

Functioni

Housekeeping enzyme that catalyzes the last step in proline biosynthesis. In some cell types, such as erythrocytes, its primary function may be the generation of NADP+. Can utilize both NAD and NADP. Has higher affinity for NADP, but higher catalytic efficiency with NADH.2 Publications

Catalytic activityi

L-proline + NAD(P)+ = 1-pyrroline-5-carboxylate + NAD(P)H.2 Publications

Enzyme regulationi

Subject to competitive inhibition by NADP. Not inhibited by proline.2 Publications

Kineticsi

  1. KM=0.64 mM for NADH1 Publication
  2. KM=0.04 mM for NADPH1 Publication
  3. KM=1.49 mM for pyrroline-5-carboxylate (in the presence of NADH)1 Publication
  4. KM=0.23 mM for pyrroline-5-carboxylate (in the presence of NADPH)1 Publication
  1. Vmax=28.5 µmol/min/µg enzyme (in the presence of NADH)1 Publication
  2. Vmax=3.7 µmol/min/µg enzyme (in the presence of NADPH)1 Publication

Pathway:iL-proline biosynthesis

This protein is involved in step 1 of the subpathway that synthesizes L-proline from L-glutamate 5-semialdehyde.
Proteins known to be involved in this subpathway in this organism are:
  1. Pyrroline-5-carboxylate reductase, Pyrroline-5-carboxylate reductase (P5CR2), Pyrroline-5-carboxylate reductase (PYCRL), Pyrroline-5-carboxylate reductase 1, mitochondrial (PYCR1), Pyrroline-5-carboxylate reductase 2 (PYCR2), Pyrroline-5-carboxylate reductase 3 (PYCRL), Pyrroline-5-carboxylate reductase (PYCR1), Pyrroline-5-carboxylate reductase (PYCR2), Pyrroline-5-carboxylate reductase (PYCRL), Pyrroline-5-carboxylate reductase (PYCR2), Pyrroline-5-carboxylate reductase (PYCR1), Pyrroline-5-carboxylate reductase (PYCR1), Pyrroline-5-carboxylate reductase
This subpathway is part of the pathway L-proline biosynthesis, which is itself part of Amino-acid biosynthesis.
View all proteins of this organism that are known to be involved in the subpathway that synthesizes L-proline from L-glutamate 5-semialdehyde, the pathway L-proline biosynthesis and in Amino-acid biosynthesis.

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Binding sitei34 – 341NADP; via carbonyl oxygenBy similarity
Binding sitei56 – 561NADPBy similarity

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi6 – 116NADPBy similarity
Nucleotide bindingi69 – 724NADPBy similarity
Nucleotide bindingi95 – 973NADPBy similarity

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Oxidoreductase

Keywords - Biological processi

Amino-acid biosynthesis, Proline biosynthesis

Keywords - Ligandi

NADP

Enzyme and pathway databases

SABIO-RKQ96C36.
UniPathwayiUPA00098; UER00361.

Names & Taxonomyi

Protein namesi
Recommended name:
Pyrroline-5-carboxylate reductase 2 (EC:1.5.1.2)
Short name:
P5C reductase 2
Short name:
P5CR 2
Gene namesi
Name:PYCR2
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 1

Organism-specific databases

HGNCiHGNC:30262. PYCR2.

Subcellular locationi

  • Cytoplasm 1 Publication

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA134881955.

Chemistry

DrugBankiDB00172. L-Proline.

Polymorphism and mutation databases

DMDMi60390642.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methioninei1 – 11Removed1 Publication
Chaini2 – 320319Pyrroline-5-carboxylate reductase 2PRO_0000187317Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei2 – 21N-acetylserine1 Publication
Modified residuei304 – 3041Phosphoserine3 Publications

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

MaxQBiQ96C36.
PaxDbiQ96C36.
PRIDEiQ96C36.

PTM databases

PhosphoSiteiQ96C36.

Expressioni

Tissue specificityi

Detected in erythrocytes (at protein level).2 Publications

Gene expression databases

BgeeiQ96C36.
CleanExiHS_PYCR2.
ExpressionAtlasiQ96C36. baseline and differential.
GenevisibleiQ96C36. HS.

Organism-specific databases

HPAiHPA056873.

Interactioni

Subunit structurei

Homodecamer; composed of 5 homodimers.1 Publication

Protein-protein interaction databases

BioGridi118962. 19 interactions.
IntActiQ96C36. 9 interactions.
MINTiMINT-1150827.
STRINGi9606.ENSP00000342502.

Structurei

3D structure databases

ProteinModelPortaliQ96C36.
SMRiQ96C36. Positions 1-275.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Sequence similaritiesi

Phylogenomic databases

eggNOGiCOG0345.
GeneTreeiENSGT00390000007443.
HOGENOMiHOG000230247.
HOVERGENiHBG053399.
InParanoidiQ96C36.
KOiK00286.
OMAiFAREEDY.
OrthoDBiEOG7N0C5N.
PhylomeDBiQ96C36.

Family and domain databases

Gene3Di1.10.3730.10. 1 hit.
3.40.50.720. 1 hit.
HAMAPiMF_01925. P5C_reductase.
InterProiIPR008927. 6-PGluconate_DH_C-like.
IPR016040. NAD(P)-bd_dom.
IPR029036. P5CR_dimer.
IPR028939. ProC_N.
IPR000304. Pyrroline-COOH_reductase.
[Graphical view]
PANTHERiPTHR11645. PTHR11645. 1 hit.
PfamiPF03807. F420_oxidored. 1 hit.
PF14748. P5CR_dimer. 1 hit.
[Graphical view]
PIRSFiPIRSF000193. Pyrrol-5-carb_rd. 1 hit.
SUPFAMiSSF48179. SSF48179. 1 hit.
TIGRFAMsiTIGR00112. proC. 1 hit.
PROSITEiPS00521. P5CR. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

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

Q96C36-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MSVGFIGAGQ LAYALARGFT AAGILSAHKI IASSPEMNLP TVSALRKMGV
60 70 80 90 100
NLTRSNKETV KHSDVLFLAV KPHIIPFILD EIGADVQARH IVVSCAAGVT
110 120 130 140 150
ISSVEKKLMA FQPAPKVIRC MTNTPVVVQE GATVYATGTH ALVEDGQLLE
160 170 180 190 200
QLMSSVGFCT EVEEDLIDAV TGLSGSGPAY AFMALDALAD GGVKMGLPRR
210 220 230 240 250
LAIQLGAQAL LGAAKMLLDS EQHPCQLKDN VCSPGGATIH ALHFLESGGF
260 270 280 290 300
RSLLINAVEA SCIRTRELQS MADQEKISPA ALKKTLLDRV KLESPTVSTL
310 320
TPSSPGKLLT RSLALGGKKD
Length:320
Mass (Da):33,637
Last modified:December 1, 2001 - v1
Checksum:i9348455A64CCE722
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti13 – 131Y → N in AAP97169 (Ref. 1) Curated
Sequence conflicti23 – 242GI → AF in AAP97169 (Ref. 1) Curated
Sequence conflicti72 – 732PH → HI in AAP97169 (Ref. 1) Curated

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF087859 mRNA. Translation: AAP97169.1.
AK291913 mRNA. Translation: BAF84602.1.
AL117348 Genomic DNA. Translation: CAI21802.1.
CH471098 Genomic DNA. Translation: EAW69762.1.
BC014868 mRNA. Translation: AAH14868.1.
BC020553 mRNA. Translation: AAH20553.1.
CCDSiCCDS31043.1.
RefSeqiNP_001258610.1. NM_001271681.1.
NP_037460.2. NM_013328.3.
UniGeneiHs.654718.

Genome annotation databases

EnsembliENST00000343818; ENSP00000342502; ENSG00000143811.
GeneIDi29920.
KEGGihsa:29920.
UCSCiuc001hpq.4. human.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF087859 mRNA. Translation: AAP97169.1.
AK291913 mRNA. Translation: BAF84602.1.
AL117348 Genomic DNA. Translation: CAI21802.1.
CH471098 Genomic DNA. Translation: EAW69762.1.
BC014868 mRNA. Translation: AAH14868.1.
BC020553 mRNA. Translation: AAH20553.1.
CCDSiCCDS31043.1.
RefSeqiNP_001258610.1. NM_001271681.1.
NP_037460.2. NM_013328.3.
UniGeneiHs.654718.

3D structure databases

ProteinModelPortaliQ96C36.
SMRiQ96C36. Positions 1-275.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi118962. 19 interactions.
IntActiQ96C36. 9 interactions.
MINTiMINT-1150827.
STRINGi9606.ENSP00000342502.

Chemistry

DrugBankiDB00172. L-Proline.

PTM databases

PhosphoSiteiQ96C36.

Polymorphism and mutation databases

DMDMi60390642.

Proteomic databases

MaxQBiQ96C36.
PaxDbiQ96C36.
PRIDEiQ96C36.

Protocols and materials databases

DNASUi29920.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000343818; ENSP00000342502; ENSG00000143811.
GeneIDi29920.
KEGGihsa:29920.
UCSCiuc001hpq.4. human.

Organism-specific databases

CTDi29920.
GeneCardsiGC01M226107.
H-InvDBHIX0200217.
HGNCiHGNC:30262. PYCR2.
HPAiHPA056873.
neXtProtiNX_Q96C36.
PharmGKBiPA134881955.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiCOG0345.
GeneTreeiENSGT00390000007443.
HOGENOMiHOG000230247.
HOVERGENiHBG053399.
InParanoidiQ96C36.
KOiK00286.
OMAiFAREEDY.
OrthoDBiEOG7N0C5N.
PhylomeDBiQ96C36.

Enzyme and pathway databases

UniPathwayiUPA00098; UER00361.
SABIO-RKQ96C36.

Miscellaneous databases

GenomeRNAii29920.
NextBioi52520.
PROiQ96C36.

Gene expression databases

BgeeiQ96C36.
CleanExiHS_PYCR2.
ExpressionAtlasiQ96C36. baseline and differential.
GenevisibleiQ96C36. HS.

Family and domain databases

Gene3Di1.10.3730.10. 1 hit.
3.40.50.720. 1 hit.
HAMAPiMF_01925. P5C_reductase.
InterProiIPR008927. 6-PGluconate_DH_C-like.
IPR016040. NAD(P)-bd_dom.
IPR029036. P5CR_dimer.
IPR028939. ProC_N.
IPR000304. Pyrroline-COOH_reductase.
[Graphical view]
PANTHERiPTHR11645. PTHR11645. 1 hit.
PfamiPF03807. F420_oxidored. 1 hit.
PF14748. P5CR_dimer. 1 hit.
[Graphical view]
PIRSFiPIRSF000193. Pyrrol-5-carb_rd. 1 hit.
SUPFAMiSSF48179. SSF48179. 1 hit.
TIGRFAMsiTIGR00112. proC. 1 hit.
PROSITEiPS00521. P5CR. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Cloning of a new human cDNA homologous to human pyrroline 5-carboxylate reductase mRNA."
    Yue P., Yu L., Zhao S.Y.
    Submitted (AUG-1998) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
  2. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
  3. "The DNA sequence and biological annotation of human chromosome 1."
    Gregory S.G., Barlow K.F., McLay K.E., Kaul R., Swarbreck D., Dunham A., Scott C.E., Howe K.L., Woodfine K., Spencer C.C.A., Jones M.C., Gillson C., Searle S., Zhou Y., Kokocinski F., McDonald L., Evans R., Phillips K.
    , Atkinson A., Cooper R., Jones C., Hall R.E., Andrews T.D., Lloyd C., Ainscough R., Almeida J.P., Ambrose K.D., Anderson F., Andrew R.W., Ashwell R.I.S., Aubin K., Babbage A.K., Bagguley C.L., Bailey J., Beasley H., Bethel G., Bird C.P., Bray-Allen S., Brown J.Y., Brown A.J., Buckley D., Burton J., Bye J., Carder C., Chapman J.C., Clark S.Y., Clarke G., Clee C., Cobley V., Collier R.E., Corby N., Coville G.J., Davies J., Deadman R., Dunn M., Earthrowl M., Ellington A.G., Errington H., Frankish A., Frankland J., French L., Garner P., Garnett J., Gay L., Ghori M.R.J., Gibson R., Gilby L.M., Gillett W., Glithero R.J., Grafham D.V., Griffiths C., Griffiths-Jones S., Grocock R., Hammond S., Harrison E.S.I., Hart E., Haugen E., Heath P.D., Holmes S., Holt K., Howden P.J., Hunt A.R., Hunt S.E., Hunter G., Isherwood J., James R., Johnson C., Johnson D., Joy A., Kay M., Kershaw J.K., Kibukawa M., Kimberley A.M., King A., Knights A.J., Lad H., Laird G., Lawlor S., Leongamornlert D.A., Lloyd D.M., Loveland J., Lovell J., Lush M.J., Lyne R., Martin S., Mashreghi-Mohammadi M., Matthews L., Matthews N.S.W., McLaren S., Milne S., Mistry S., Moore M.J.F., Nickerson T., O'Dell C.N., Oliver K., Palmeiri A., Palmer S.A., Parker A., Patel D., Pearce A.V., Peck A.I., Pelan S., Phelps K., Phillimore B.J., Plumb R., Rajan J., Raymond C., Rouse G., Saenphimmachak C., Sehra H.K., Sheridan E., Shownkeen R., Sims S., Skuce C.D., Smith M., Steward C., Subramanian S., Sycamore N., Tracey A., Tromans A., Van Helmond Z., Wall M., Wallis J.M., White S., Whitehead S.L., Wilkinson J.E., Willey D.L., Williams H., Wilming L., Wray P.W., Wu Z., Coulson A., Vaudin M., Sulston J.E., Durbin R.M., Hubbard T., Wooster R., Dunham I., Carter N.P., McVean G., Ross M.T., Harrow J., Olson M.V., Beck S., Rogers J., Bentley D.R.
    Nature 441:315-321(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  4. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  5. "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: Cervix and Skin.
  6. Bienvenut W.V., Heiserich L., Gottlieb E., Zebisch A., Kolch W.
    Submitted (OCT-2008) to UniProtKB
    Cited for: PROTEIN SEQUENCE OF 2-17, CLEAVAGE OF INITIATOR METHIONINE, ACETYLATION AT SER-2, IDENTIFICATION BY MASS SPECTROMETRY.
    Tissue: Colon carcinoma.
  7. "Pyrroline-5-carboxylate reductase in human erythrocytes."
    Yeh G.C., Harris S.C., Phang J.M.
    J. Clin. Invest. 67:1042-1046(1981) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, CATALYTIC ACTIVITY, ENZYME REGULATION, TISSUE SPECIFICITY.
  8. "Purified human erythrocyte pyrroline-5-carboxylate reductase. Preferential oxidation of NADPH."
    Merrill M.J., Yeh G.C., Phang J.M.
    J. Biol. Chem. 264:9352-9358(1989) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, CATALYTIC ACTIVITY, SUBUNIT, SUBCELLULAR LOCATION, ENZYME REGULATION, BIOPHYSICOCHEMICAL PROPERTIES, TISSUE SPECIFICITY.
  9. "A probability-based approach for high-throughput protein phosphorylation analysis and site localization."
    Beausoleil S.A., Villen J., Gerber S.A., Rush J., Gygi S.P.
    Nat. Biotechnol. 24:1285-1292(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  10. Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-304, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  11. "Lys-N and trypsin cover complementary parts of the phosphoproteome in a refined SCX-based approach."
    Gauci S., Helbig A.O., Slijper M., Krijgsveld J., Heck A.J., Mohammed S.
    Anal. Chem. 81:4493-4501(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  12. "Quantitative phosphoproteomics reveals widespread full phosphorylation site occupancy during mitosis."
    Olsen J.V., Vermeulen M., Santamaria A., Kumar C., Miller M.L., Jensen L.J., Gnad F., Cox J., Jensen T.S., Nigg E.A., Brunak S., Mann M.
    Sci. Signal. 3:RA3-RA3(2010) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-304, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  13. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  14. "System-wide temporal characterization of the proteome and phosphoproteome of human embryonic stem cell differentiation."
    Rigbolt K.T., Prokhorova T.A., Akimov V., Henningsen J., Johansen P.T., Kratchmarova I., Kassem M., Mann M., Olsen J.V., Blagoev B.
    Sci. Signal. 4:RS3-RS3(2011) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-304, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].

Entry informationi

Entry nameiP5CR2_HUMAN
AccessioniPrimary (citable) accession number: Q96C36
Secondary accession number(s): A8K798, Q7Z515, Q9Y5J4
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 1, 2005
Last sequence update: December 1, 2001
Last modified: July 22, 2015
This is version 117 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

Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 1
    Human chromosome 1: entries, gene names and cross-references to MIM
  2. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  3. 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.