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Protein

50S ribosomal protein L18

Gene

rplR

Organism
Escherichia coli (strain K12)
Status
Reviewed-Annotation score: Annotation score: 4 out of 5-Experimental evidence at protein leveli

Functioni

This is one of the proteins that mediates the attachment of the 5S rRNA subcomplex onto the large ribosomal subunit where it forms part of the central protuberance. Binds stably to 5S rRNA; increases binding abilities of L5 in a cooperative fashion; both proteins together confer 23S rRNA binding. The 5S rRNA and some of its associated proteins might help stabilize positioning of ribosome-bound tRNAs.5 Publications

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Ribonucleoprotein, Ribosomal protein

Keywords - Ligandi

RNA-binding, rRNA-binding

Enzyme and pathway databases

BioCyciEcoCyc:EG10879-MONOMER.
ECOL316407:JW3266-MONOMER.

Names & Taxonomyi

Protein namesi
Recommended name:
50S ribosomal protein L18
Gene namesi
Name:rplR
Ordered Locus Names:b3304, JW3266
OrganismiEscherichia coli (strain K12)
Taxonomic identifieri83333 [NCBI]
Taxonomic lineageiBacteriaProteobacteriaGammaproteobacteriaEnterobacterialesEnterobacteriaceaeEscherichia
ProteomesiUP000000318 Componenti: Chromosome UP000000625 Componenti: Chromosome

Organism-specific databases

EcoGeneiEG10879. rplR.

Subcellular locationi

GO - Cellular componenti

  • cytosolic large ribosomal subunit Source: EcoCyc
Complete GO annotation...

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 11711750S ribosomal protein L18PRO_0000131258Add
BLAST

Post-translational modificationi

The protein has been shown to contain a phosphoserine, which was required for the protein to bind to 5S rRNA (PubMed:10529214). However, the presence of this phosphoserine is controversial, and it has not been seen by mass spectrometry.1 Publication

Keywords - PTMi

Phosphoprotein

Proteomic databases

PaxDbiP0C018.
PRIDEiP0C018.

Expressioni

Gene expression databases

GenevestigatoriP0C018.

Interactioni

Subunit structurei

Part of the 50S ribosomal subunit; part of the 5S rRNA/L5/L18/L25 subcomplex. Contacts the 5S and 23S rRNAs.2 Publications

Protein-protein interaction databases

DIPiDIP-47908N.
IntActiP0C018. 35 interactions.
MINTiMINT-1293631.
STRINGi511145.b3304.

Structurei

Secondary structure

1
117
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi3 – 97Combined sources
Helixi12 – 2110Combined sources
Beta strandi25 – 317Combined sources
Beta strandi34 – 407Combined sources
Beta strandi44 – 463Combined sources
Beta strandi47 – 504Combined sources
Beta strandi53 – 553Combined sources
Helixi56 – 605Combined sources
Beta strandi62 – 643Combined sources
Beta strandi65 – 673Combined sources
Helixi68 – 8316Combined sources
Turni84 – 863Combined sources
Beta strandi91 – 933Combined sources
Beta strandi99 – 1013Combined sources
Helixi102 – 11211Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1ML5electron microscopy14.00q2-117[»]
2J28electron microscopy8.00O1-117[»]
2RDOelectron microscopy9.10O1-117[»]
3BBXelectron microscopy10.00O1-117[»]
3J5Lelectron microscopy6.60O2-117[»]
3J7Zelectron microscopy3.90O1-117[»]
4CSUelectron microscopy5.50O2-117[»]
4U1UX-ray2.95BO/DO2-117[»]
4U1VX-ray3.00BO/DO2-117[»]
4U20X-ray2.90BO/DO2-117[»]
4U24X-ray2.90BO/DO2-117[»]
4U25X-ray2.90BO/DO2-117[»]
4U26X-ray2.80BO/DO2-117[»]
4U27X-ray2.80BO/DO2-117[»]
4UY8electron microscopy3.80O2-117[»]
4V47electron microscopy12.30AM1-117[»]
4V48electron microscopy11.50AM1-117[»]
4V4HX-ray3.46BO/DO1-117[»]
4V4QX-ray3.46BO/DO1-117[»]
4V4Velectron microscopy15.00BM3-115[»]
4V4Welectron microscopy15.00BM3-115[»]
4V50X-ray3.22BO/DO1-117[»]
4V52X-ray3.21BO/DO1-117[»]
4V53X-ray3.54BO/DO1-117[»]
4V54X-ray3.30BO/DO1-117[»]
4V55X-ray4.00BO/DO1-117[»]
4V56X-ray3.93BO/DO1-117[»]
4V57X-ray3.50BO/DO1-117[»]
4V5BX-ray3.74AO/CO1-117[»]
4V5Helectron microscopy5.80BO2-117[»]
4V5YX-ray4.45BO/DO1-117[»]
4V64X-ray3.50BO/DO1-117[»]
4V65electron microscopy9.00BH1-117[»]
4V66electron microscopy9.00BH1-117[»]
4V69electron microscopy6.70BO2-117[»]
4V6CX-ray3.19BO/DO1-117[»]
4V6DX-ray3.81BO/DO1-117[»]
4V6EX-ray3.71BO/DO1-117[»]
4V6Kelectron microscopy8.25AP1-117[»]
4V6Lelectron microscopy13.20BP1-117[»]
4V6Melectron microscopy7.10BO1-117[»]
4V6Nelectron microscopy12.10AQ1-117[»]
4V6Oelectron microscopy14.70BQ1-117[»]
4V6Pelectron microscopy13.50BQ1-117[»]
4V6Qelectron microscopy11.50BQ1-117[»]
4V6Relectron microscopy11.50BQ1-117[»]
4V6Selectron microscopy13.10AQ1-117[»]
4V6Telectron microscopy8.30BO2-117[»]
4V6Velectron microscopy9.80BS1-117[»]
4V6Yelectron microscopy12.00BO1-117[»]
4V6Zelectron microscopy12.00BO1-117[»]
4V70electron microscopy17.00BO1-117[»]
4V71electron microscopy20.00BO1-117[»]
4V72electron microscopy13.00BO1-117[»]
4V73electron microscopy15.00BO1-117[»]
4V74electron microscopy17.00BO1-117[»]
4V75electron microscopy12.00BO1-117[»]
4V76electron microscopy17.00BO1-117[»]
4V77electron microscopy17.00BO1-117[»]
4V78electron microscopy20.00BO1-117[»]
4V79electron microscopy15.00BO1-117[»]
4V7Aelectron microscopy9.00BO1-117[»]
4V7Belectron microscopy6.80BO1-117[»]
4V7Celectron microscopy7.60BQ1-117[»]
4V7Delectron microscopy7.60AR1-117[»]
4V7Ielectron microscopy9.60AO1-117[»]
4V7SX-ray3.25BO/DO2-117[»]
4V7TX-ray3.19BO/DO2-117[»]
4V7UX-ray3.10BO/DO2-117[»]
4V7VX-ray3.29BO/DO2-117[»]
4V85X-ray3.20S1-117[»]
4V89X-ray3.70BS1-117[»]
4V9CX-ray3.30BO/DO1-117[»]
4V9DX-ray3.00CO/DO2-117[»]
4V9OX-ray2.90AO/CO/EO/GO1-117[»]
4V9PX-ray2.90AO/CO/EO/GO1-117[»]
4WF1X-ray3.09BO/DO2-117[»]
4WWWX-ray3.10RO/YO2-117[»]
4YBBX-ray2.10CP/DP1-117[»]
5AFIelectron microscopy2.90O1-117[»]
5AKAelectron microscopy5.70O1-117[»]
ProteinModelPortaliP0C018.
SMRiP0C018. Positions 2-117.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP0C018.

Family & Domainsi

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni1 – 1717Required for binding of the 5S rRNA/L5/L18 complex to the 23S rRNA1 PublicationAdd
BLAST

Domaini

The basic N-terminus is not necessary for binding to 5S rRNA. It is however required for cooperative binding of L5 and L18 to 5S rRNA as well as for binding of the 5S rRNA/L5/L18 complex to the 23S rRNA.1 Publication

Sequence similaritiesi

Belongs to the ribosomal protein L18P family.Curated

Phylogenomic databases

eggNOGiCOG0256.
HOGENOMiHOG000248742.
InParanoidiP0C018.
KOiK02881.
OMAiNKYHGRI.
OrthoDBiEOG64NB48.
PhylomeDBiP0C018.

Family and domain databases

HAMAPiMF_01337_B. Ribosomal_L18_B.
InterProiIPR005484. Ribosomal_L18/L5.
IPR004389. Ribosomal_L18_bac-type.
[Graphical view]
PfamiPF00861. Ribosomal_L18p. 1 hit.
[Graphical view]
TIGRFAMsiTIGR00060. L18_bact. 1 hit.

Sequencei

Sequence statusi: Complete.

P0C018-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MDKKSARIRR ATRARRKLQE LGATRLVVHR TPRHIYAQVI APNGSEVLVA
60 70 80 90 100
ASTVEKAIAE QLKYTGNKDA AAAVGKAVAE RALEKGIKDV SFDRSGFQYH
110
GRVQALADAA REAGLQF
Length:117
Mass (Da):12,770
Last modified:July 21, 1986 - v1
Checksum:iCA1082FF9B5D9697
GO

Mass spectrometryi

Molecular mass is 12769.8 Da from positions 1 - 117. Determined by MALDI. 1 Publication

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X01563 Genomic DNA. Translation: CAA25721.1.
U18997 Genomic DNA. Translation: AAA58101.1.
U00096 Genomic DNA. Translation: AAC76329.1.
AP009048 Genomic DNA. Translation: BAE77987.1.
PIRiA02803. R5EC18.
RefSeqiNP_417763.1. NC_000913.3.

Genome annotation databases

EnsemblBacteriaiAAC76329; AAC76329; b3304.
BAE77987; BAE77987; BAE77987.
GeneIDi947804.
KEGGiecj:Y75_p3872.
eco:b3304.
PATRICi32122040. VBIEscCol129921_3397.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X01563 Genomic DNA. Translation: CAA25721.1.
U18997 Genomic DNA. Translation: AAA58101.1.
U00096 Genomic DNA. Translation: AAC76329.1.
AP009048 Genomic DNA. Translation: BAE77987.1.
PIRiA02803. R5EC18.
RefSeqiNP_417763.1. NC_000913.3.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1ML5electron microscopy14.00q2-117[»]
2J28electron microscopy8.00O1-117[»]
2RDOelectron microscopy9.10O1-117[»]
3BBXelectron microscopy10.00O1-117[»]
3J5Lelectron microscopy6.60O2-117[»]
3J7Zelectron microscopy3.90O1-117[»]
4CSUelectron microscopy5.50O2-117[»]
4U1UX-ray2.95BO/DO2-117[»]
4U1VX-ray3.00BO/DO2-117[»]
4U20X-ray2.90BO/DO2-117[»]
4U24X-ray2.90BO/DO2-117[»]
4U25X-ray2.90BO/DO2-117[»]
4U26X-ray2.80BO/DO2-117[»]
4U27X-ray2.80BO/DO2-117[»]
4UY8electron microscopy3.80O2-117[»]
4V47electron microscopy12.30AM1-117[»]
4V48electron microscopy11.50AM1-117[»]
4V4HX-ray3.46BO/DO1-117[»]
4V4QX-ray3.46BO/DO1-117[»]
4V4Velectron microscopy15.00BM3-115[»]
4V4Welectron microscopy15.00BM3-115[»]
4V50X-ray3.22BO/DO1-117[»]
4V52X-ray3.21BO/DO1-117[»]
4V53X-ray3.54BO/DO1-117[»]
4V54X-ray3.30BO/DO1-117[»]
4V55X-ray4.00BO/DO1-117[»]
4V56X-ray3.93BO/DO1-117[»]
4V57X-ray3.50BO/DO1-117[»]
4V5BX-ray3.74AO/CO1-117[»]
4V5Helectron microscopy5.80BO2-117[»]
4V5YX-ray4.45BO/DO1-117[»]
4V64X-ray3.50BO/DO1-117[»]
4V65electron microscopy9.00BH1-117[»]
4V66electron microscopy9.00BH1-117[»]
4V69electron microscopy6.70BO2-117[»]
4V6CX-ray3.19BO/DO1-117[»]
4V6DX-ray3.81BO/DO1-117[»]
4V6EX-ray3.71BO/DO1-117[»]
4V6Kelectron microscopy8.25AP1-117[»]
4V6Lelectron microscopy13.20BP1-117[»]
4V6Melectron microscopy7.10BO1-117[»]
4V6Nelectron microscopy12.10AQ1-117[»]
4V6Oelectron microscopy14.70BQ1-117[»]
4V6Pelectron microscopy13.50BQ1-117[»]
4V6Qelectron microscopy11.50BQ1-117[»]
4V6Relectron microscopy11.50BQ1-117[»]
4V6Selectron microscopy13.10AQ1-117[»]
4V6Telectron microscopy8.30BO2-117[»]
4V6Velectron microscopy9.80BS1-117[»]
4V6Yelectron microscopy12.00BO1-117[»]
4V6Zelectron microscopy12.00BO1-117[»]
4V70electron microscopy17.00BO1-117[»]
4V71electron microscopy20.00BO1-117[»]
4V72electron microscopy13.00BO1-117[»]
4V73electron microscopy15.00BO1-117[»]
4V74electron microscopy17.00BO1-117[»]
4V75electron microscopy12.00BO1-117[»]
4V76electron microscopy17.00BO1-117[»]
4V77electron microscopy17.00BO1-117[»]
4V78electron microscopy20.00BO1-117[»]
4V79electron microscopy15.00BO1-117[»]
4V7Aelectron microscopy9.00BO1-117[»]
4V7Belectron microscopy6.80BO1-117[»]
4V7Celectron microscopy7.60BQ1-117[»]
4V7Delectron microscopy7.60AR1-117[»]
4V7Ielectron microscopy9.60AO1-117[»]
4V7SX-ray3.25BO/DO2-117[»]
4V7TX-ray3.19BO/DO2-117[»]
4V7UX-ray3.10BO/DO2-117[»]
4V7VX-ray3.29BO/DO2-117[»]
4V85X-ray3.20S1-117[»]
4V89X-ray3.70BS1-117[»]
4V9CX-ray3.30BO/DO1-117[»]
4V9DX-ray3.00CO/DO2-117[»]
4V9OX-ray2.90AO/CO/EO/GO1-117[»]
4V9PX-ray2.90AO/CO/EO/GO1-117[»]
4WF1X-ray3.09BO/DO2-117[»]
4WWWX-ray3.10RO/YO2-117[»]
4YBBX-ray2.10CP/DP1-117[»]
5AFIelectron microscopy2.90O1-117[»]
5AKAelectron microscopy5.70O1-117[»]
ProteinModelPortaliP0C018.
SMRiP0C018. Positions 2-117.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

DIPiDIP-47908N.
IntActiP0C018. 35 interactions.
MINTiMINT-1293631.
STRINGi511145.b3304.

Chemistry

ChEMBLiCHEMBL2363135.

Proteomic databases

PaxDbiP0C018.
PRIDEiP0C018.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblBacteriaiAAC76329; AAC76329; b3304.
BAE77987; BAE77987; BAE77987.
GeneIDi947804.
KEGGiecj:Y75_p3872.
eco:b3304.
PATRICi32122040. VBIEscCol129921_3397.

Organism-specific databases

EchoBASEiEB0872.
EcoGeneiEG10879. rplR.

Phylogenomic databases

eggNOGiCOG0256.
HOGENOMiHOG000248742.
InParanoidiP0C018.
KOiK02881.
OMAiNKYHGRI.
OrthoDBiEOG64NB48.
PhylomeDBiP0C018.

Enzyme and pathway databases

BioCyciEcoCyc:EG10879-MONOMER.
ECOL316407:JW3266-MONOMER.

Miscellaneous databases

EvolutionaryTraceiP0C018.
PROiP0C018.

Gene expression databases

GenevestigatoriP0C018.

Family and domain databases

HAMAPiMF_01337_B. Ribosomal_L18_B.
InterProiIPR005484. Ribosomal_L18/L5.
IPR004389. Ribosomal_L18_bac-type.
[Graphical view]
PfamiPF00861. Ribosomal_L18p. 1 hit.
[Graphical view]
TIGRFAMsiTIGR00060. L18_bact. 1 hit.
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "The primary structure of the 5S RNA binding protein L18 from Escherichia coli ribosomes."
    Brosius J., Schiltz E., Chen R.
    FEBS Lett. 56:359-361(1975) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE.
    Strain: K.
  2. "The spc ribosomal protein operon of Escherichia coli: sequence and cotranscription of the ribosomal protein genes and a protein export gene."
    Cerretti D.P., Dean D., Davis G.R., Bedwell D.M., Nomura M.
    Nucleic Acids Res. 11:2599-2616(1983) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    Strain: K12.
  3. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: K12 / MG1655 / ATCC 47076.
  4. "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.
  5. "Stoichiometry, cooperativity, and stability of interactions between 5S RNA and proteins L5, L18, and L25 from the 50S ribosomal subunit of Escherichia coli."
    Spierer P., Zimmermann R.A.
    Biochemistry 17:2474-2479(1978) [PubMed] [Europe PMC] [Abstract]
    Cited for: FORMATION OF THE 5S RRNA/L5/L18/L25 SUBCOMPLEX.
  6. "Fragment of protein L18 from the Escherichia coli ribosome that contains the 5S RNA binding site."
    Newberry V., Brosius J., Garrett R.
    Nucleic Acids Res. 5:1753-1766(1978) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION OF THE BASIC N-TERMINUS.
  7. "Cooperative interactions among protein and RNA components of the 50S ribosomal subunit of Escherichia coli."
    Spierer P., Wang C.-C., Marsh T.L., Zimmermann R.A.
    Nucleic Acids Res. 6:1669-1682(1979) [PubMed] [Europe PMC] [Abstract]
    Cited for: ASSOCIATION OF 5S RRNA/L5/L18 WITH 23S RRNA.
    Strain: MRE-600.
  8. "The role of the basic N-terminal region of protein L18 in 5S RNA-23S RNA complex formation."
    Newberry V., Garrett R.A.
    Nucleic Acids Res. 8:4131-4142(1980) [PubMed] [Europe PMC] [Abstract]
    Cited for: REQUIREMENT OF N-TERMINUS FOR FORMATION OF 5S RRNA-23S RRNA COMPLEX.
    Strain: MRE-600.
  9. "Assembly map of the large subunit (50S) of Escherichia coli ribosomes."
    Rohl R., Nierhaus K.H.
    Proc. Natl. Acad. Sci. U.S.A. 79:729-733(1982) [PubMed] [Europe PMC] [Abstract]
    Cited for: REQUIREMENT FOR INCORPORATION OF 5S RRNA INTO THE 50S SUBUNIT.
    Strain: MRE-600.
  10. "5S rRNA sugar-phosphate backbone protection in complexes with specific ribosomal proteins."
    Shpanchenko O.V., Zvereva M.I., Dontsova O.A., Nierhaus K.H., Bogdanov A.A.
    FEBS Lett. 394:71-75(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: CHARACTERIZATION OF A 5S RRNA/L5/L18/L25 SUBCOMPLEX.
    Strain: K12 / A19.
  11. "Phosphorylation of ribosomal protein L18 is required for its folding and binding to 5S rRNA."
    Bloemink M.J., Moore P.B.
    Biochemistry 38:13385-13390(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION.
  12. "Observation of Escherichia coli ribosomal proteins and their posttranslational modifications by mass spectrometry."
    Arnold R.J., Reilly J.P.
    Anal. Biochem. 269:105-112(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: MASS SPECTROMETRY.
    Strain: K12 / ATCC 25404 / DSM 5698 / NCIMB 11290.
  13. "Study of the structural dynamics of the E. coli 70S ribosome using real-space refinement."
    Gao H., Sengupta J., Valle M., Korostelev A., Eswar N., Stagg S.M., Van Roey P., Agrawal R.K., Harvey S.C., Sali A., Chapman M.S., Frank J.
    Cell 113:789-801(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: STRUCTURE BY ELECTRON MICROSCOPY (11.50 ANGSTROMS).
    Strain: MRE-600.
  14. Cited for: X-RAY CRYSTALLOGRAPHY (3.46 ANGSTROMS) OF 2 DIFFERENT RIBOSOME STRUCTURES.
    Strain: MRE-600.
  15. "Molecular basis for the ribosome functioning as an L-tryptophan sensor."
    Bischoff L., Berninghausen O., Beckmann R.
    Cell Rep. 9:469-475(2014) [PubMed] [Europe PMC] [Abstract]
    Cited for: STRUCTURE BY ELECTRON MICROSCOPY (3.80 ANGSTROMS) OF 2-117 IN TNAC-STALLED 50S RIBOSOMAL SUBUNIT.
    Strain: K12 / A19 / KC6.

Entry informationi

Entry nameiRL18_ECOLI
AccessioniPrimary (citable) accession number: P0C018
Secondary accession number(s): P02419, Q2M6W9
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 21, 1986
Last modified: May 27, 2015
This is version 100 of the entry and version 1 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. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  3. Ribosomal proteins
    Ribosomal proteins families and list of entries
  4. 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.