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Protein

Probable pectinesterase/pectinesterase inhibitor 32

Gene

PME32

Organism
Arabidopsis thaliana (Mouse-ear cress)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at transcript leveli

Functioni

Acts in the modification of cell walls via demethylesterification of cell wall pectin.By similarity

Catalytic activityi

Pectin + n H2O = n methanol + pectate.

Pathwayi: pectin degradation

This protein is involved in step 1 of the subpathway that synthesizes 2-dehydro-3-deoxy-D-gluconate from pectin.
Proteins known to be involved in the 5 steps of the subpathway in this organism are:
  1. Probable pectinesterase/pectinesterase inhibitor 7 (PME7), Pectinesterase (AXX17_At1g11890), Pectinesterase (AXX17_At4g02940), Pectinesterase (AXX17_At5g52320), Probable pectinesterase/pectinesterase inhibitor 42 (PME42), Probable pectinesterase 15 (PME15), Putative pectinesterase 14 (PME14), Pectinesterase (At3g10720), Pectinesterase (AXX17_At2g33410), Probable pectinesterase 55 (PME55), Probable pectinesterase/pectinesterase inhibitor 23 (PME23), Pectinesterase (AXX17_At4g18720), Pectinesterase 4 (PME4), Putative pectinesterase/pectinesterase inhibitor 22 (PME22), Pectinesterase (AXX17_At1g48290), Pectinesterase (AXX17_At5g47900), Pectinesterase (At3g14310), Pectinesterase (AXX17_At4g38050), Pectinesterase (AXX17_At5g07100), Pectinesterase/pectinesterase inhibitor 18 (PME18), Pectinesterase (AXX17_At2g14510), Pectinesterase (AXX17_At3g43380), Pectinesterase (AXX17_At5g64270), Probable pectinesterase/pectinesterase inhibitor 64 (PME64), Putative pectinesterase 10 (PME10), Pectinesterase (F14I3.7), Probable pectinesterase 29 (PME29), Pectinesterase, Pectinesterase (AXX17_At4g38040), Probable pectinesterase 8 (PME8), Pectinesterase (AXX17_At5g27870), Pectinesterase (AXX17_At5g18820), Pectinesterase (AXX17_At2g45340), Pectinesterase 31 (PME31), Pectinesterase (AXX17_At3g41380), Pectinesterase (AXX17_At1g11650), Probable pectinesterase/pectinesterase inhibitor 25 (PME25), Probable pectinesterase/pectinesterase inhibitor 51 (PME51), Pectinesterase (AXX17_At3g36460), Pectinesterase (AXX17_At5g04430), Pectinesterase (At3g62170), Probable pectinesterase/pectinesterase inhibitor 20 (PME20), Pectinesterase (T27B3.30), Probable pectinesterase/pectinesterase inhibitor 60 (PME60), Probable pectinesterase/pectinesterase inhibitor 59 (PME59), Pectinesterase QRT1 (QRT1), Pectinesterase (AXX17_At3g53530), Pectinesterase (AXX17_At5g61190), Pectinesterase PPME1 (PPME1), Pectinesterase (AXX17_At3g56460), Pectinesterase (AXX17_At3g06710), Probable pectinesterase/pectinesterase inhibitor 32 (PME32), Pectinesterase (AXX17_At1g44540), Probable pectinesterase/pectinesterase inhibitor 33 (PME33), Probable pectinesterase/pectinesterase inhibitor 36 (PME36), Probable pectinesterase/pectinesterase inhibitor 13 (PME13), Putative pectinesterase 52 (PME52), Probable pectinesterase/pectinesterase inhibitor 54 (PME54), Pectinesterase (AXX17_At2g33420), Pectinesterase (AXX17_At2g40510), Pectinesterase (At1g53840), Pectinesterase 5 (PME5), Probable pectinesterase/pectinesterase inhibitor 16 (PME16), Probable pectinesterase 30 (PME30), Probable pectinesterase/pectinesterase inhibitor VGDH2 (VGDH2), Pectinesterase (AXX17_At3g26070), Probable pectinesterase 68 (PME68), Pectinesterase, Pectinesterase (AXX17_At3g14900), Pectinesterase (AXX17_At5g54740), Probable pectinesterase 67 (PME67), Putative pectinesterase/pectinesterase inhibitor 38 (PME38), Probable pectinesterase 56 (PME56), Pectinesterase, Probable pectinesterase/pectinesterase inhibitor 47 (PME47), Putative pectinesterase/pectinesterase inhibitor 28 (PME28), Probable pectinesterase 53 (PME53), Probable pectinesterase/pectinesterase inhibitor 46 (PME46), Pectinesterase (AXX17_At5g07090), Probable pectinesterase/pectinesterase inhibitor 17 (PME17), Pectinesterase (AXX17_At2g22270), Probable pectinesterase/pectinesterase inhibitor 61 (PME61), Probable pectinesterase 66 (PME66), Pectinesterase (AXX17_At2g42790), Pectinesterase (AXX17_At5g45990), Probable pectinesterase/pectinesterase inhibitor 6 (PME6), Probable pectinesterase 48 (PME48), Probable pectinesterase 49 (PME49), Pectinesterase (AXX17_At1g64100), Probable pectinesterase 50 (PME50), Pectinesterase (AXX17_At3g17940), Pectinesterase, Probable pectinesterase/pectinesterase inhibitor 19 (PME19), Pectinesterase (AXX17_At2g45050), Probable pectinesterase/pectinesterase inhibitor 40 (PME40), Pectinesterase (AXX17_At1g11920), Pectinesterase (AXX17_At3g30550), PME26 (AXX17_At3g14890), Probable pectinesterase/pectinesterase inhibitor 39 (PME39), Pectinesterase (AXX17_At2g44790), Pectinesterase (AXX17_At2g17140), Pectinesterase (AXX17_At5g19650), Putative pectinesterase/pectinesterase inhibitor 43 (PME43), Pectinesterase (AXX17_At3g31890), Pectinesterase (AXX17_At4g02900), Probable pectinesterase/pectinesterase inhibitor 34 (PME34), Pectinesterase 1 (PME1), Putative pectinesterase 63 (PME63), Pectinesterase (AXX17_At3g05180), Pectinesterase 2 (PME2), Probable pectinesterase/pectinesterase inhibitor 21 (PME21), Pectinesterase (AXX17_At2g22280), Pectinesterase (AXX17_At1g51200), Putative pectinesterase/pectinesterase inhibitor 45 (PME45), Probable pectinesterase/pectinesterase inhibitor 12 (PME12), Pectinesterase (AXX17_At4g02930), Probable pectinesterase/pectinesterase inhibitor 44 (PME44), Pectinesterase, Pectinesterase/pectinesterase inhibitor 3 (PME3), Pectinesterase (AXX17_At1g24390), Pectinesterase (AXX17_At5g50300), Pectinesterase (AXX17_At1g11900), Probable pectinesterase/pectinesterase inhibitor 58 (PME58), Putative pectinesterase 57 (PME57), Pectinesterase (AXX17_At3g10560), Pectinesterase (AXX17_At3g55110), Pectinesterase (AXX17_At3g10570), Putative pectinesterase 11 (PME11), Pectinesterase (AXX17_At1g01970), Pectinesterase (AXX17_At5g07110), Pectinesterase (AXX17_At4g06570), Pectinesterase (AXX17_At5g50310), Pectinesterase, Pectinesterase (AXX17_At1g51190), Pectinesterase (AXX17_At2g33420), Pectinesterase (AXX17_At1g48300), Pectinesterase (AXX17_At3g05190), Putative pectinesterase/pectinesterase inhibitor 24 (PME24), Putative pectinesterase/pectinesterase inhibitor 26 (PME26), Probable pectinesterase/pectinesterase inhibitor 35 (PME35), Pectinesterase (AXX17_At5g04420), Pectinesterase (AXX17_At2g44780), Pectinesterase (AXX17_At4g00230), Pectinesterase (AXX17_At5g09310), Pectinesterase (AXX17_At5g20800), Pectinesterase (AXX17_At1g04730), Probable pectinesterase/pectinesterase inhibitor 41 (PME41), Pectinesterase (AXX17_At1g11660), Pectinesterase (AXX17_At5g26780)
  2. Pectate lyase (AXX17_At3g26720), Probable pectate lyase 7 (At3g01270), Probable pectate lyase 18 (At4g24780), Probable pectate lyase 16 (At4g22080), Putative pectate lyase 17 (At4g22090), Pectate lyase (AXX17_At3g09180), Putative pectate lyase 14 (At4g13210), Pectate lyase (At3g55140), Pectate lyase (AXX17_At5g54880), Pectate lyase (AXX17_At4g15660), Probable pectate lyase 22 (At5g63180), Pectate lyase (T5E8_80), Pectate lyase (AXX17_At3g00310), Pectate lyase (At3g07010), Probable pectate lyase 8 (At3g07010), Probable pectate lyase 4 (At1g30350), Pectate lyase (AXX17_At2g01680), Putative pectate lyase 21 (At5g55720), Pectate lyase (At4g13210), Pectate lyase (At5g04310), Pectate lyase (AXX17_At5g03700), Pectate lyase (At4g13710), Pectate lyase (AXX17_At3g49720), Pectate lyase (At3g01270), Pectate lyase (At5g04310), Pectate lyase (AXX17_At1g12300), Probable pectate lyase 9 (At3g24230), Probable pectate lyase 1 (At1g04680), Pectate lyase (AXX17_At5g08800), Pectate lyase (T26I12.20), Pectate lyase (AXX17_At5g62760), Pectate lyase (AXX17_At3g47590), Pectate lyase (AXX17_At4g14900), Pectate lyase (AXX17_At3g49450), Pectate lyase (AXX17_At4g25600), Pectate lyase (AXX17_At1g61710), Probable pectate lyase 20 (At5g48900), Pectate lyase (AXX17_At5g47570), Probable pectate lyase 6 (At2g02720), Pectate lyase (AXX17_At3g06910), Pectate lyase (At1g14420), Pectate lyase (At3g01270), Pectate lyase (At2g02720), Pectate lyase (AXX17_At1g04020), Pectate lyase (At3g01270), Pectate lyase (At3g55140), Putative pectate lyase 2 (At1g11920), Pectate lyase, Pectate lyase (AXX17_At1g30780), Probable pectate lyase 19 (At5g15110), Pectate lyase (F11F8_12), Probable pectate lyase 13 (PMR6), Probable pectate lyase 3 (AT59), Pectate lyase (AXX17_At3g26200), Probable pectate lyase 5 (At1g67750), Probable pectate lyase 12 (At3g53190), Pectate lyase (At4g24780), Pectate lyase (AXX17_At4g25610), Probable pectate lyase 15 (At4g13710), Pectate lyase (At3g53190), Putative pectate lyase 11 (At3g27400), Pectate lyase (AXX17_At1g15010), Pectate lyase (At3g07010), Pectate lyase (AXX17_At3g29900), Pectate lyase (AXX17_At5g14600), Probable pectate lyase 10 (At3g24670)
  3. no protein annotated in this organism
  4. no protein annotated in this organism
  5. no protein annotated in this organism
This subpathway is part of the pathway pectin degradation, which is itself part of Glycan metabolism.
View all proteins of this organism that are known to be involved in the subpathway that synthesizes 2-dehydro-3-deoxy-D-gluconate from pectin, the pathway pectin degradation and in Glycan metabolism.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Binding sitei289Substrate; for pectinesterase activityBy similarity1
Binding sitei319Substrate; for pectinesterase activityBy similarity1
Sitei341Transition state stabilizerBy similarity1
Active sitei342Proton donor; for pectinesterase activityPROSITE-ProRule annotation1
Active sitei363Nucleophile; for pectinesterase activityPROSITE-ProRule annotation1
Binding sitei431Substrate; for pectinesterase activityBy similarity1
Binding sitei433Substrate; for pectinesterase activityBy similarity1

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Aspartyl esterase, Hydrolase

Keywords - Biological processi

Cell wall biogenesis/degradation

Enzyme and pathway databases

BioCyciARA:AT3G43270-MONOMER.
UniPathwayiUPA00545; UER00823.

Names & Taxonomyi

Protein namesi
Recommended name:
Probable pectinesterase/pectinesterase inhibitor 32
Including the following 2 domains:
Pectinesterase inhibitor 32
Alternative name(s):
Pectin methylesterase inhibitor 32
Pectinesterase 32 (EC:3.1.1.11)
Short name:
PE 32
Alternative name(s):
Pectin methylesterase 32
Short name:
AtPME32
Gene namesi
Name:PME32
Synonyms:ARATH32
Ordered Locus Names:At3g43270
ORF Names:F7K15.120
OrganismiArabidopsis thaliana (Mouse-ear cress)
Taxonomic identifieri3702 [NCBI]
Taxonomic lineageiEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaerosidsmalvidsBrassicalesBrassicaceaeCamelineaeArabidopsis
Proteomesi
  • UP000006548 Componenti: Chromosome 3

Organism-specific databases

TAIRiAT3G43270.

Subcellular locationi

GO - Cellular componenti

  • cell periphery Source: GO_Central
  • extracellular region Source: UniProtKB-KW
  • plant-type cell wall Source: TAIR
Complete GO annotation...

Keywords - Cellular componenti

Cell wall, Secreted

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Signal peptidei1 – 24Sequence analysisAdd BLAST24
ChainiPRO_000037168425 – 527Probable pectinesterase/pectinesterase inhibitor 32Add BLAST503

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Glycosylationi110N-linked (GlcNAc...)Sequence analysis1
Glycosylationi209N-linked (GlcNAc...)Sequence analysis1
Glycosylationi224N-linked (GlcNAc...)Sequence analysis1
Glycosylationi280N-linked (GlcNAc...)Sequence analysis1
Disulfide bondi356 ↔ 376By similarity
Glycosylationi423N-linked (GlcNAc...)Sequence analysis1
Glycosylationi494N-linked (GlcNAc...)Sequence analysis1
Glycosylationi501N-linked (GlcNAc...)Sequence analysis1

Keywords - PTMi

Disulfide bond, Glycoprotein

Proteomic databases

PaxDbiQ9LXK7.
PRIDEiQ9LXK7.

PTM databases

iPTMnetiQ9LXK7.

Expressioni

Tissue specificityi

Expressed in siliques.1 Publication

Developmental stagei

Expressed during late developmental phases of siliques.1 Publication

Gene expression databases

GenevisibleiQ9LXK7. AT.

Interactioni

Protein-protein interaction databases

STRINGi3702.AT3G43270.1.

Structurei

3D structure databases

ProteinModelPortaliQ9LXK7.
SMRiQ9LXK7.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni25 – 165Pectinesterase inhibitor 32Add BLAST141
Regioni214 – 511Pectinesterase 32Add BLAST298

Compositional bias

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Compositional biasi259 – 262Poly-Lys4

Sequence similaritiesi

In the N-terminal section; belongs to the PMEI family.Curated
In the C-terminal section; belongs to the pectinesterase family.Curated

Keywords - Domaini

Signal

Phylogenomic databases

eggNOGiENOG410IGVA. Eukaryota.
COG4677. LUCA.
HOGENOMiHOG000217409.
InParanoidiQ9LXK7.
KOiK01051.
OMAiFRECIIT.
OrthoDBiEOG093607M8.
PhylomeDBiQ9LXK7.

Family and domain databases

Gene3Di1.20.140.40. 1 hit.
2.160.20.10. 1 hit.
InterProiIPR012334. Pectin_lyas_fold.
IPR011050. Pectin_lyase_fold/virulence.
IPR033131. Pectinesterase_Asp_AS.
IPR000070. Pectinesterase_cat.
IPR006501. Pectinesterase_inhib_dom.
IPR018040. Pectinesterase_Tyr_AS.
[Graphical view]
PfamiPF01095. Pectinesterase. 1 hit.
PF04043. PMEI. 1 hit.
[Graphical view]
SMARTiSM00856. PMEI. 1 hit.
[Graphical view]
SUPFAMiSSF101148. SSF101148. 1 hit.
SSF51126. SSF51126. 1 hit.
TIGRFAMsiTIGR01614. PME_inhib. 1 hit.
PROSITEiPS00800. PECTINESTERASE_1. 1 hit.
PS00503. PECTINESTERASE_2. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

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

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q9LXK7-1) [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
MAKFRQMGSS IFFLFLIIIS LCSAHKEAFS STDLVQMECL RVPPLEFAEA
60 70 80 90 100
AKTVVDAITK AVAIVSKFDK KAGKSRVSNA IVDCVDLLDS AAEELSWIIS
110 120 130 140 150
ASQSPNGKDN STGDVGSDLR TWISAALSNQ DTCLDGFEGT NGIIKKIVAG
160 170 180 190 200
GLSKVGTTVR NLLTMVHSPP SKPKPKPIKA QTMTKAHSGF SKFPSWVKPG
210 220 230 240 250
DRKLLQTDNI TVADAVVAAD GTGNFTTISD AVLAAPDYST KRYVIHVKRG
260 270 280 290 300
VYVENVEIKK KKWNIMMVGD GIDATVITGN RSFIDGWTTF RSATFAVSGR
310 320 330 340 350
GFIARDITFQ NTAGPEKHQA VAIRSDTDLG VFYRCAMRGY QDTLYAHSMR
360 370 380 390 400
QFFRECIITG TVDFIFGDAT AVFQSCQIKA KQGLPNQKNS ITAQGRKDPN
410 420 430 440 450
EPTGFTIQFS NIAADTDLLL NLNTTATYLG RPWKLYSRTV FMQNYMSDAI
460 470 480 490 500
NPVGWLEWNG NFALDTLYYG EYMNSGPGAS LDRRVKWPGY HVLNTSAEAN
510 520
NFTVSQLIQG NLWLPSTGIT FIAGLVS
Length:527
Mass (Da):57,636
Last modified:October 1, 2000 - v1
Checksum:iCBC47903AB23A29C
GO
Isoform 2 (identifier: Q9LXK7-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     296-305: AVSGRGFIAR → GKSKFIISFT
     306-527: Missing.

Show »
Length:305
Mass (Da):32,937
Checksum:i3051D91851FB7AD5
GO

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_037089296 – 305AVSGRGFIAR → GKSKFIISFT in isoform 2. 1 Publication10
Alternative sequenceiVSP_037090306 – 527Missing in isoform 2. 1 PublicationAdd BLAST222

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AL353871 Genomic DNA. Translation: CAB89048.1.
CP002686 Genomic DNA. Translation: AEE77781.1.
AY070071 mRNA. Translation: AAL49828.1.
AY096694 mRNA. Translation: AAM20328.1.
AY065349 mRNA. Translation: AAL38790.1.
AY096720 mRNA. Translation: AAM20354.1.
PIRiT49241.
RefSeqiNP_189913.3. NM_114195.4. [Q9LXK7-1]
UniGeneiAt.28622.

Genome annotation databases

EnsemblPlantsiAT3G43270.1; AT3G43270.1; AT3G43270. [Q9LXK7-1]
GeneIDi823402.
GrameneiAT3G43270.1; AT3G43270.1; AT3G43270.
KEGGiath:AT3G43270.

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AL353871 Genomic DNA. Translation: CAB89048.1.
CP002686 Genomic DNA. Translation: AEE77781.1.
AY070071 mRNA. Translation: AAL49828.1.
AY096694 mRNA. Translation: AAM20328.1.
AY065349 mRNA. Translation: AAL38790.1.
AY096720 mRNA. Translation: AAM20354.1.
PIRiT49241.
RefSeqiNP_189913.3. NM_114195.4. [Q9LXK7-1]
UniGeneiAt.28622.

3D structure databases

ProteinModelPortaliQ9LXK7.
SMRiQ9LXK7.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

STRINGi3702.AT3G43270.1.

PTM databases

iPTMnetiQ9LXK7.

Proteomic databases

PaxDbiQ9LXK7.
PRIDEiQ9LXK7.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblPlantsiAT3G43270.1; AT3G43270.1; AT3G43270. [Q9LXK7-1]
GeneIDi823402.
GrameneiAT3G43270.1; AT3G43270.1; AT3G43270.
KEGGiath:AT3G43270.

Organism-specific databases

TAIRiAT3G43270.

Phylogenomic databases

eggNOGiENOG410IGVA. Eukaryota.
COG4677. LUCA.
HOGENOMiHOG000217409.
InParanoidiQ9LXK7.
KOiK01051.
OMAiFRECIIT.
OrthoDBiEOG093607M8.
PhylomeDBiQ9LXK7.

Enzyme and pathway databases

UniPathwayiUPA00545; UER00823.
BioCyciARA:AT3G43270-MONOMER.

Miscellaneous databases

PROiQ9LXK7.

Gene expression databases

GenevisibleiQ9LXK7. AT.

Family and domain databases

Gene3Di1.20.140.40. 1 hit.
2.160.20.10. 1 hit.
InterProiIPR012334. Pectin_lyas_fold.
IPR011050. Pectin_lyase_fold/virulence.
IPR033131. Pectinesterase_Asp_AS.
IPR000070. Pectinesterase_cat.
IPR006501. Pectinesterase_inhib_dom.
IPR018040. Pectinesterase_Tyr_AS.
[Graphical view]
PfamiPF01095. Pectinesterase. 1 hit.
PF04043. PMEI. 1 hit.
[Graphical view]
SMARTiSM00856. PMEI. 1 hit.
[Graphical view]
SUPFAMiSSF101148. SSF101148. 1 hit.
SSF51126. SSF51126. 1 hit.
TIGRFAMsiTIGR01614. PME_inhib. 1 hit.
PROSITEiPS00800. PECTINESTERASE_1. 1 hit.
PS00503. PECTINESTERASE_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiPME32_ARATH
AccessioniPrimary (citable) accession number: Q9LXK7
Secondary accession number(s): Q8VZ27
Entry historyi
Integrated into UniProtKB/Swiss-Prot: May 5, 2009
Last sequence update: October 1, 2000
Last modified: November 30, 2016
This is version 100 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programPlant Protein Annotation Program

Miscellaneousi

Miscellaneous

The PMEI region may act as an autoinhibitory domain and prevent untimely PME activity during transport.

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. Arabidopsis thaliana
    Arabidopsis thaliana: entries and gene names
  2. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  3. 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.