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Protein

Molybdopterin biosynthesis protein CNX1

Gene

CNX1

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

Functioni

Catalyzes two steps in the biosynthesis of the molybdenum cofactor. In the first step, molybdopterin is adenylated. Subsequently, molybdate is inserted into adenylated molybdopterin and AMP is released.4 Publications

Catalytic activityi

Adenylyl-molybdopterin + molybdate = molybdenum cofactor + AMP.
ATP + molybdopterin = diphosphate + adenylyl-molybdopterin.

Cofactori

Mg2+2 Publications

Enzyme regulationi

Inhibited by copper and tungsten.1 Publication

Kineticsi

  1. KM=62 µM for ATP for domain G2 Publications
  2. KM=133 µM for Zn2+ for domain E2 Publications
  3. KM=255 µM for Mg2+ for domain E2 Publications

    Pathway: molybdopterin biosynthesis

    This protein is involved in the pathway molybdopterin biosynthesis, which is part of Cofactor biosynthesis.
    View all proteins of this organism that are known to be involved in the pathway molybdopterin biosynthesis and in Cofactor biosynthesis.

    Sites

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Binding sitei485 – 4851AMP
    Binding sitei486 – 4861AMP; via amide nitrogen
    Binding sitei541 – 5411AMP; via amide nitrogen
    Binding sitei573 – 5731Substrate1 Publication
    Binding sitei600 – 6001AMP; via carbonyl oxygen
    Binding sitei600 – 6001Substrate; via amide nitrogen1 Publication
    Binding sitei607 – 6071Substrate1 Publication

    GO - Molecular functioni

    GO - Biological processi

    Complete GO annotation...

    Keywords - Molecular functioni

    Transferase

    Keywords - Biological processi

    Molybdenum cofactor biosynthesis

    Keywords - Ligandi

    ATP-binding, Magnesium, Metal-binding, Molybdenum, Nucleotide-binding

    Enzyme and pathway databases

    BRENDAi2.10.1.1. 399.
    2.7.7.75. 399.
    ReactomeiREACT_291701. Molybdenum cofactor biosynthesis.
    UniPathwayiUPA00344.

    Names & Taxonomyi

    Protein namesi
    Recommended name:
    Molybdopterin biosynthesis protein CNX1
    Alternative name(s):
    Molybdenum cofactor biosynthesis enzyme CNX1
    Including the following 2 domains:
    Molybdopterin molybdenumtransferase (EC:2.10.1.1)
    Short name:
    MPT Mo-transferase
    Alternative name(s):
    Domain E
    Molybdopterin adenylyltransferase (EC:2.7.7.75)
    Short name:
    MPT adenylyltransferase
    Alternative name(s):
    Domain G
    Gene namesi
    Name:CNX1
    Ordered Locus Names:At5g20990
    ORF Names:F22D1.6, T10F18.20
    OrganismiArabidopsis thaliana (Mouse-ear cress)
    Taxonomic identifieri3702 [NCBI]
    Taxonomic lineageiEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaerosidsmalvidsBrassicalesBrassicaceaeCamelineaeArabidopsis
    ProteomesiUP000006548 Componenti: Chromosome 5

    Organism-specific databases

    TAIRiAT5G20990.

    Subcellular locationi

    GO - Cellular componenti

    • cytoplasm Source: GO_Central
    • cytosol Source: TAIR
    Complete GO annotation...

    Pathology & Biotechi

    Mutagenesis

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Mutagenesisi475 – 4751S → D: Reduced molybdopterin binding. Loss of adenylation activity. 1 Publication
    Mutagenesisi485 – 4851D → S: Reduced molybdopterin binding. Loss of adenylation activity. 1 Publication
    Mutagenesisi515 – 5151D → H or N: Almost normal molybdopterin binding. Loss adenylation activity. 2 Publications
    Mutagenesisi542 – 5421T → A: Strongly reduced molybdopterin binding. Reduced activity. 1 Publication
    Mutagenesisi542 – 5421T → D or N: Loss of molybdopterin binding. Loss of activity. 1 Publication
    Mutagenesisi542 – 5421T → S: Reduced molybdopterin binding. No effect on activity. 1 Publication
    Mutagenesisi542 – 5421T → V: Strongly reduced molybdopterin binding. No effect on activity. 1 Publication
    Mutagenesisi547 – 5471R → E: No effect on molybdopterin binding. Clear reduction in adenylation activity. 1 Publication
    Mutagenesisi557 – 5571V → G: Impaired folding. Loss of activity. 1 Publication
    Mutagenesisi573 – 5731S → A: Loss of molybdopterin binding. Loss of activity. 1 Publication
    Mutagenesisi583 – 5831S → A: No effect on activity. 1 Publication
    Mutagenesisi597 – 5971N → L: Loss of molybdopterin binding. Loss of activity. 1 Publication

    PTM / Processingi

    Molecule processing

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Chaini1 – 670670Molybdopterin biosynthesis protein CNX1PRO_0000170963Add
    BLAST

    Proteomic databases

    PaxDbiQ39054.
    PRIDEiQ39054.

    Interactioni

    Subunit structurei

    The G domain: homotrimer or homohexamer. The E domain: homodimer.4 Publications

    Protein-protein interaction databases

    BioGridi17499. 2 interactions.
    MINTiMINT-8070811.
    STRINGi3702.AT5G20990.1.

    Structurei

    Secondary structure

    1
    670
    Legend: HelixTurnBeta strand
    Show more details
    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Beta strandi466 – 4749Combined sources
    Helixi476 – 4794Combined sources
    Helixi487 – 49711Combined sources
    Turni498 – 5036Combined sources
    Beta strandi504 – 51310Combined sources
    Helixi517 – 52913Combined sources
    Beta strandi534 – 5407Combined sources
    Beta strandi543 – 5453Combined sources
    Helixi550 – 5578Combined sources
    Beta strandi559 – 5613Combined sources
    Helixi563 – 57614Combined sources
    Helixi578 – 5825Combined sources
    Beta strandi587 – 5904Combined sources
    Beta strandi593 – 5986Combined sources
    Helixi604 – 62320Combined sources

    3D structure databases

    Select the link destinations:
    PDBei
    RCSB PDBi
    PDBji
    Links Updated
    EntryMethodResolution (Å)ChainPositionsPDBsum
    1EAVX-ray2.60A/B/C/D/E/F/G/H462-623[»]
    1O8NX-ray2.80A/B/C462-628[»]
    1O8OX-ray2.70A/B/C462-628[»]
    1O8QX-ray2.60A/B/C/D/E/F/G/H462-628[»]
    1UUXX-ray1.60A462-623[»]
    1UUYX-ray1.45A462-624[»]
    ProteinModelPortaliQ39054.
    SMRiQ39054. Positions 20-416, 464-623.
    ModBaseiSearch...
    MobiDBiSearch...

    Miscellaneous databases

    EvolutionaryTraceiQ39054.

    Family & Domainsi

    Region

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Regioni19 – 439421MPT Mo-transferaseAdd
    BLAST
    Regioni466 – 620155MPT adenylyltransferaseAdd
    BLAST
    Regioni542 – 5432Substrate binding

    Compositional bias

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Compositional biasi8 – 125Poly-Gly

    Sequence similaritiesi

    In the N-terminal section; belongs to the MoaB/Mog family.Curated
    In the C-terminal section; belongs to the MoeA family.Curated

    Phylogenomic databases

    eggNOGiCOG0303.
    HOGENOMiHOG000280651.
    InParanoidiQ39054.
    KOiK15376.
    OMAiKITPFAM.
    PhylomeDBiQ39054.

    Family and domain databases

    Gene3Di2.40.340.10. 1 hit.
    3.40.980.10. 2 hits.
    InterProiIPR001453. MoaB/Mog_dom.
    IPR008284. MoCF_biosynth_CS.
    IPR005111. MoeA_C_domain_IV.
    IPR005110. MoeA_linker/N.
    [Graphical view]
    PfamiPF00994. MoCF_biosynth. 2 hits.
    PF03454. MoeA_C. 1 hit.
    PF03453. MoeA_N. 1 hit.
    [Graphical view]
    SMARTiSM00852. MoCF_biosynth. 2 hits.
    [Graphical view]
    SUPFAMiSSF53218. SSF53218. 2 hits.
    SSF63867. SSF63867. 1 hit.
    SSF63882. SSF63882. 1 hit.
    TIGRFAMsiTIGR00177. molyb_syn. 2 hits.
    PROSITEiPS01078. MOCF_BIOSYNTHESIS_1. 1 hit.
    PS01079. MOCF_BIOSYNTHESIS_2. 1 hit.
    [Graphical view]

    Sequencei

    Sequence statusi: Complete.

    Q39054-1 [UniParc]FASTAAdd to basket

    « Hide

            10         20         30         40         50
    MEGQGCCGGG GGKTEMIPTE EALRIVFGVS KRLPPVIVSL YEALGKVLAE
    60 70 80 90 100
    DIRAPDPLPP YPASVKDGYA VVASDGPGEY PVITESRAGN DGLGVTVTPG
    110 120 130 140 150
    TVAYVTTGGP IPDGADAVVQ VEDTKVIGDV STESKRVKIL IQTKKGTDIR
    160 170 180 190 200
    RVGCDIEKDA TVLTTGERIG ASEIGLLATA GVTMVKVYPM PIVAILSTGD
    210 220 230 240 250
    ELVEPTAGTL GRGQIRDSNR AMLVAAVMQQ QCKVVDLGIV RDDRKELEKV
    260 270 280 290 300
    LDEAVSSGVD IILTSGGVSM GDRDFVKPLL EEKGKVYFSK VLMKPGKPLT
    310 320 330 340 350
    FAEIRAKPTE SMLGKTVLAF GLPGNPVSCL VCFNIFVVPT IRQLAGWTSP
    360 370 380 390 400
    HPLRVRLRLQ EPIKSDPIRP EFHRAIIKWK DNDGSGTPGF VAESTGHQMS
    410 420 430 440 450
    SRLLSMRSAN ALLELPATGN VLSAGSSVSA IIVSDISAFS IDKKASLSEP
    460 470 480 490 500
    GSIRKEKKYD EVPGPEYKVA ILTVSDTVSA GAGPDRSGPR AVSVVDSSSE
    510 520 530 540 550
    KLGGAKVVAT AVVPDEVERI KDILQKWSDV DEMDLILTLG GTGFTPRDVT
    560 570 580 590 600
    PEATKKVIER ETPGLLFVMM QESLKITPFA MLSRSAAGIR GSTLIINMPG
    610 620 630 640 650
    NPNAVAECME ALLPALKHAL KQIKGDKREK HPKHIPHAEA TLPTDTWDQS
    660 670
    YKSAYETGEK KEEAGCSCTH
    Length:670
    Mass (Da):71,279
    Last modified:December 6, 2002 - v2
    Checksum:i4405722BB9C5EF02
    GO

    Experimental Info

    Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
    Sequence conflicti113 – 1131D → V (PubMed:8528286).Curated
    Sequence conflicti113 – 1131D → V (Ref. 2) Curated
    Sequence conflicti134 – 1341S → A (PubMed:8528286).Curated
    Sequence conflicti134 – 1341S → A (Ref. 2) Curated
    Sequence conflicti653 – 6531S → L (PubMed:8528286).Curated
    Sequence conflicti653 – 6531S → L (Ref. 2) Curated

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    L47323 mRNA. Translation: AAA97413.1.
    AJ236870 Genomic DNA. Translation: CAB38312.1.
    AC069325 Genomic DNA. No translation available.
    AF296834 Genomic DNA. No translation available.
    CP002688 Genomic DNA. Translation: AED92917.1.
    RefSeqiNP_197599.1. NM_122108.3.
    UniGeneiAt.23035.

    Genome annotation databases

    EnsemblPlantsiAT5G20990.1; AT5G20990.1; AT5G20990.
    GeneIDi832224.
    KEGGiath:AT5G20990.

    Cross-referencesi

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    L47323 mRNA. Translation: AAA97413.1.
    AJ236870 Genomic DNA. Translation: CAB38312.1.
    AC069325 Genomic DNA. No translation available.
    AF296834 Genomic DNA. No translation available.
    CP002688 Genomic DNA. Translation: AED92917.1.
    RefSeqiNP_197599.1. NM_122108.3.
    UniGeneiAt.23035.

    3D structure databases

    Select the link destinations:
    PDBei
    RCSB PDBi
    PDBji
    Links Updated
    EntryMethodResolution (Å)ChainPositionsPDBsum
    1EAVX-ray2.60A/B/C/D/E/F/G/H462-623[»]
    1O8NX-ray2.80A/B/C462-628[»]
    1O8OX-ray2.70A/B/C462-628[»]
    1O8QX-ray2.60A/B/C/D/E/F/G/H462-628[»]
    1UUXX-ray1.60A462-623[»]
    1UUYX-ray1.45A462-624[»]
    ProteinModelPortaliQ39054.
    SMRiQ39054. Positions 20-416, 464-623.
    ModBaseiSearch...
    MobiDBiSearch...

    Protein-protein interaction databases

    BioGridi17499. 2 interactions.
    MINTiMINT-8070811.
    STRINGi3702.AT5G20990.1.

    Proteomic databases

    PaxDbiQ39054.
    PRIDEiQ39054.

    Protocols and materials databases

    Structural Biology KnowledgebaseSearch...

    Genome annotation databases

    EnsemblPlantsiAT5G20990.1; AT5G20990.1; AT5G20990.
    GeneIDi832224.
    KEGGiath:AT5G20990.

    Organism-specific databases

    TAIRiAT5G20990.

    Phylogenomic databases

    eggNOGiCOG0303.
    HOGENOMiHOG000280651.
    InParanoidiQ39054.
    KOiK15376.
    OMAiKITPFAM.
    PhylomeDBiQ39054.

    Enzyme and pathway databases

    UniPathwayiUPA00344.
    BRENDAi2.10.1.1. 399.
    2.7.7.75. 399.
    ReactomeiREACT_291701. Molybdenum cofactor biosynthesis.

    Miscellaneous databases

    EvolutionaryTraceiQ39054.
    PROiQ39054.

    Family and domain databases

    Gene3Di2.40.340.10. 1 hit.
    3.40.980.10. 2 hits.
    InterProiIPR001453. MoaB/Mog_dom.
    IPR008284. MoCF_biosynth_CS.
    IPR005111. MoeA_C_domain_IV.
    IPR005110. MoeA_linker/N.
    [Graphical view]
    PfamiPF00994. MoCF_biosynth. 2 hits.
    PF03454. MoeA_C. 1 hit.
    PF03453. MoeA_N. 1 hit.
    [Graphical view]
    SMARTiSM00852. MoCF_biosynth. 2 hits.
    [Graphical view]
    SUPFAMiSSF53218. SSF53218. 2 hits.
    SSF63867. SSF63867. 1 hit.
    SSF63882. SSF63882. 1 hit.
    TIGRFAMsiTIGR00177. molyb_syn. 2 hits.
    PROSITEiPS01078. MOCF_BIOSYNTHESIS_1. 1 hit.
    PS01079. MOCF_BIOSYNTHESIS_2. 1 hit.
    [Graphical view]
    ProtoNetiSearch...

    Publicationsi

    « Hide 'large scale' publications
    1. "Molybdenum co-factor biosynthesis: the Arabidopsis thaliana cDNA cnx1 encodes a multifunctional two-domain protein homologous to a mammalian neuroprotein, the insect protein Cinnamon and three Escherichia coli proteins."
      Stallmeyer B., Nerlich A., Schiemann J., Brinkmann H., Mendel R.R.
      Plant J. 8:751-762(1995) [PubMed] [Europe PMC] [Abstract]
      Cited for: NUCLEOTIDE SEQUENCE [MRNA].
      Strain: cv. Columbia.
    2. "Sequence of the Arabidopsis thaliana gene cnx1 that is involved in the last step of molybdenum cofactor biosynthesis."
      Brinkmann H., Schledzewski K., Nerlich A., Bollmann G., Stallmeyer B., Mendel R.R.
      Submitted (MAR-1999) to the EMBL/GenBank/DDBJ databases
      Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
      Strain: cv. Columbia.
    3. "Sequence and analysis of chromosome 5 of the plant Arabidopsis thaliana."
      Tabata S., Kaneko T., Nakamura Y., Kotani H., Kato T., Asamizu E., Miyajima N., Sasamoto S., Kimura T., Hosouchi T., Kawashima K., Kohara M., Matsumoto M., Matsuno A., Muraki A., Nakayama S., Nakazaki N., Naruo K.
      , Okumura S., Shinpo S., Takeuchi C., Wada T., Watanabe A., Yamada M., Yasuda M., Sato S., de la Bastide M., Huang E., Spiegel L., Gnoj L., O'Shaughnessy A., Preston R., Habermann K., Murray J., Johnson D., Rohlfing T., Nelson J., Stoneking T., Pepin K., Spieth J., Sekhon M., Armstrong J., Becker M., Belter E., Cordum H., Cordes M., Courtney L., Courtney W., Dante M., Du H., Edwards J., Fryman J., Haakensen B., Lamar E., Latreille P., Leonard S., Meyer R., Mulvaney E., Ozersky P., Riley A., Strowmatt C., Wagner-McPherson C., Wollam A., Yoakum M., Bell M., Dedhia N., Parnell L., Shah R., Rodriguez M., Hoon See L., Vil D., Baker J., Kirchoff K., Toth K., King L., Bahret A., Miller B., Marra M.A., Martienssen R., McCombie W.R., Wilson R.K., Murphy G., Bancroft I., Volckaert G., Wambutt R., Duesterhoeft A., Stiekema W., Pohl T., Entian K.-D., Terryn N., Hartley N., Bent E., Johnson S., Langham S.-A., McCullagh B., Robben J., Grymonprez B., Zimmermann W., Ramsperger U., Wedler H., Balke K., Wedler E., Peters S., van Staveren M., Dirkse W., Mooijman P., Klein Lankhorst R., Weitzenegger T., Bothe G., Rose M., Hauf J., Berneiser S., Hempel S., Feldpausch M., Lamberth S., Villarroel R., Gielen J., Ardiles W., Bents O., Lemcke K., Kolesov G., Mayer K.F.X., Rudd S., Schoof H., Schueller C., Zaccaria P., Mewes H.-W., Bevan M., Fransz P.F.
      Nature 408:823-826(2000) [PubMed] [Europe PMC] [Abstract]
      Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
      Strain: cv. Columbia.
    4. The Arabidopsis Information Resource (TAIR)
      Submitted (APR-2011) to the EMBL/GenBank/DDBJ databases
      Cited for: GENOME REANNOTATION.
      Strain: cv. Columbia.
    5. "Molybdenum cofactor biosynthesis. The plant protein Cnx1 binds molybdopterin with high affinity."
      Schwarz G., Boxer D.H., Mendel R.R.
      J. Biol. Chem. 272:26811-26814(1997) [PubMed] [Europe PMC] [Abstract]
      Cited for: BINDING OF MPT TO DOMAIN G, SUBUNIT.
    6. "Mutations in the molybdenum cofactor biosynthetic protein Cnx1G from Arabidopsis thaliana define functions for molybdopterin binding, molybdenum insertion, and molybdenum cofactor stabilization."
      Kuper J., Palmer T., Mendel R.R., Schwarz G.
      Proc. Natl. Acad. Sci. U.S.A. 97:6475-6480(2000) [PubMed] [Europe PMC] [Abstract]
      Cited for: MUTAGENESIS OF ASP-515; VAL-557 AND ASN-597.
    7. "Synthesis of adenylated molybdopterin: an essential step for molybdenum insertion."
      Llamas A., Mendel R.R., Schwarz G.
      J. Biol. Chem. 279:55241-55246(2004) [PubMed] [Europe PMC] [Abstract]
      Cited for: FUNCTION OF DOMAIN G AS MPT ADENYLYLTRANSFERASE, CATALYTIC ACTIVITY, SUBSTRATE SPECIFICITY, COFACTOR, MUTAGENESIS, BIOPHYSICOCHEMICAL PROPERTIES.
    8. "The Mechanism of nucleotide-assisted molybdenum insertion into molybdopterin. A novel route toward metal cofactor assembly."
      Llamas A., Otte T., Multhaup G., Mendel R.R., Schwarz G.
      J. Biol. Chem. 281:18343-18350(2006) [PubMed] [Europe PMC] [Abstract]
      Cited for: FUNCTION OF DOMAIN E AS MOLYBDENUM--MPT-AMP LIGASE, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES, REACTION MECHANISM.
    9. "Crystal structures of human gephyrin and plant Cnx1 G domains: comparative analysis and functional implications."
      Schwarz G., Schrader N., Mendel R.R., Hecht H.-J., Schindelin H.
      J. Mol. Biol. 312:405-418(2001) [PubMed] [Europe PMC] [Abstract]
      Cited for: X-RAY CRYSTALLOGRAPHY (2.6 ANGSTROMS) OF 462-623, SUBUNIT.
    10. "The active site of the molybdenum cofactor biosynthetic protein domain Cnx1G."
      Kuper J., Winking J., Hecht H.-J., Mendel R.R., Schwarz G.
      Arch. Biochem. Biophys. 411:36-46(2003) [PubMed] [Europe PMC] [Abstract]
      Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) OF 462-628 OF MUTANTS ALA/ASP-542 AND ALA-573, FUNCTION, MUTAGENESIS OF SER-475; ASP-485; ASP-515; THR-542; ARG-547 AND SER-573, SUBUNIT.
    11. "Structure of the molybdopterin-bound Cnx1G domain links molybdenum and copper metabolism."
      Kuper J., Llamas A., Hecht H.-J., Mendel R.R., Schwarz G.
      Nature 430:803-806(2004) [PubMed] [Europe PMC] [Abstract]
      Cited for: X-RAY CRYSTALLOGRAPHY (1.45 ANGSTROMS) OF 462-623 OF WILD-TYPE AND MUTANT ALA-583 IN COMPLEX WITH SUBSTRATE, FUNCTION, COFACTOR, ENZYME REGULATION, SUBUNIT.

    Entry informationi

    Entry nameiCNX1_ARATH
    AccessioniPrimary (citable) accession number: Q39054
    Entry historyi
    Integrated into UniProtKB/Swiss-Prot: November 1, 1997
    Last sequence update: December 6, 2002
    Last modified: June 24, 2015
    This is version 133 of the entry and version 2 of the sequence. [Complete history]
    Entry statusiReviewed (UniProtKB/Swiss-Prot)
    Annotation programPlant Protein Annotation Program

    Miscellaneousi

    Keywords - Technical termi

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

    Documents

    1. Arabidopsis thaliana
      Arabidopsis thaliana: entries and gene names
    2. PATHWAY comments
      Index of metabolic and biosynthesis pathways
    3. PDB cross-references
      Index of Protein Data Bank (PDB) cross-references
    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.