Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Isoleucine--tRNA ligase

Gene

ileS

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

Functioni

Catalyzes the attachment of isoleucine to tRNA(Ile). As IleRS can inadvertently accommodate and process structurally similar amino acids such as valine, to avoid such errors it has two additional distinct tRNA(Ile)-dependent editing activities. One activity is designated as 'pretransfer' editing and involves the hydrolysis of activated Val-AMP. The other activity is designated 'posttransfer' editing and involves deacylation of mischarged Val-tRNA(Ile).

Miscellaneous

Strain PS102 is resistant to the antibiotic mupirocin (pseudomonic acid A), an Ile-analog that competitively inhibits activation by Ile-tRNA synthetase, thus inhibiting protein biosynthesis.

Catalytic activityi

ATP + L-isoleucine + tRNA(Ile) = AMP + diphosphate + L-isoleucyl-tRNA(Ile).

Cofactori

Zn2+Note: Binds 1 zinc ion per subunit.

Kineticsi

  1. KM=5 µM for isoleucine1 Publication
  2. KM=0.4 mM for ATP1 Publication

    Sites

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Binding sitei561Aminoacyl-adenylateBy similarity1
    Binding sitei605ATPBy similarity1
    Metal bindingi901ZincBy similarity1
    Metal bindingi904ZincBy similarity1
    Metal bindingi921ZincBy similarity1
    Metal bindingi924ZincBy similarity1

    GO - Molecular functioni

    GO - Biological processi

    Keywordsi

    Molecular functionAminoacyl-tRNA synthetase, Ligase
    Biological processAntibiotic resistance, Protein biosynthesis
    LigandATP-binding, Metal-binding, Nucleotide-binding, Zinc

    Enzyme and pathway databases

    BioCyciEcoCyc:ILES-MONOMER
    MetaCyc:ILES-MONOMER

    Names & Taxonomyi

    Protein namesi
    Recommended name:
    Isoleucine--tRNA ligase (EC:6.1.1.5)
    Alternative name(s):
    Isoleucyl-tRNA synthetase
    Short name:
    IleRS
    Gene namesi
    Name:ileS
    Synonyms:ilvS
    Ordered Locus Names:b0026, JW0024
    OrganismiEscherichia coli (strain K12)
    Taxonomic identifieri83333 [NCBI]
    Taxonomic lineageiBacteriaProteobacteriaGammaproteobacteriaEnterobacteralesEnterobacteriaceaeEscherichia
    Proteomesi
    • UP000000318 Componenti: Chromosome
    • UP000000625 Componenti: Chromosome

    Organism-specific databases

    EcoGeneiEG10492 ileS

    Subcellular locationi

    GO - Cellular componenti

    Keywords - Cellular componenti

    Cytoplasm

    Pathology & Biotechi

    Mutagenesis

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Mutagenesisi94G → R: 6000-fold increase in Km for isoleucine and 4-fold increase in Km for ATP, with no effect on activity. 1 Publication1
    Mutagenesisi97C → S: No effect on activity. 1 Publication1
    Mutagenesisi102I → N: No significant effect on activity. 1 Publication1
    Mutagenesisi183K → A: Abolishes translocation from the aminoacylation site to the editing site, without effect on aminoacylation activity and posttransfer editing; when associated with A-421. 1 Publication1
    Mutagenesisi241T → A: Nearly the same editing activity as the wild-type. 1 Publication1
    Mutagenesisi242T → A: Abolishes editing activity against valine, with little change in aminoacylation activity; when associated with A-250. 1 Publication1
    Mutagenesisi242T → P: Abolishes editing activity against valine, with little change in aminoacylation activity. 1 Publication1
    Mutagenesisi243T → A: Abolishes editing activity against valine, with little change in aminoacylation activity. 2 Publications1
    Mutagenesisi243T → R: Abolishes pretransfer editing. 2 Publications1
    Mutagenesisi246T → A: Nearly the same editing activity as the wild-type. 1 Publication1
    Mutagenesisi250N → A: Abolishes editing activity against valine, with little change in aminoacylation activity. 2 Publications1
    Mutagenesisi333H → A: Alters the specificity for hydrolysis of the aminoacyl tRNA ester, with no effect on pretransfer editing. 1 Publication1
    Mutagenesisi342D → A or N: Strong decrease in total editing and deacylation activities. Severely deficient in translocation from the aminoacylation site to the editing site. 1 Publication1
    Mutagenesisi342D → E: Reduces 2- to 3-fold the total editing activity and 2-fold the deacylation activity. Moderately reduces translocation from the aminoacylation site to the editing site. 1 Publication1
    Mutagenesisi421W → A: Abolishes translocation from the aminoacylation site to the editing site, without effect on aminoacylation activity and posttransfer editing; when associated with A-183. 1 Publication1

    Chemistry databases

    ChEMBLiCHEMBL3657

    PTM / Processingi

    Molecule processing

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Initiator methionineiRemoved1 Publication
    ChainiPRO_00000983842 – 938Isoleucine--tRNA ligaseAdd BLAST937

    Amino acid modifications

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Modified residuei183N6-acetyllysine1 Publication1

    Keywords - PTMi

    Acetylation

    Proteomic databases

    EPDiP00956
    PaxDbiP00956
    PRIDEiP00956

    PTM databases

    iPTMnetiP00956

    Interactioni

    Subunit structurei

    Monomer.

    Binary interactionsi

    Protein-protein interaction databases

    BioGridi4261375, 35 interactors
    849163, 1 interactor
    DIPiDIP-10017N
    IntActiP00956, 17 interactors
    STRINGi316385.ECDH10B_0027

    Chemistry databases

    BindingDBiP00956

    Structurei

    3D structure databases

    ProteinModelPortaliP00956
    ModBaseiSearch...
    MobiDBiSearch...

    Family & Domainsi

    Motif

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Motifi58 – 68"HIGH" regionAdd BLAST11
    Motifi602 – 606"KMSKS" region5

    Domaini

    IleRS has two distinct active sites: one for aminoacylation and one for editing. The misactivated valine is translocated from the active site to the editing site, which sterically excludes the correctly activated isoleucine. The single editing site contains two valyl binding pockets, one specific for each substrate (Val-AMP or Val-tRNA(Ile)).

    Sequence similaritiesi

    Phylogenomic databases

    eggNOGiENOG4105C07 Bacteria
    COG0060 LUCA
    HOGENOMiHOG000246402
    InParanoidiP00956
    KOiK01870
    PhylomeDBiP00956

    Family and domain databases

    CDDicd07960 Anticodon_Ia_Ile_BEm, 1 hit
    Gene3Di3.40.50.620, 1 hit
    3.90.740.10, 1 hit
    HAMAPiMF_02002 Ile_tRNA_synth_type1, 1 hit
    InterProiView protein in InterPro
    IPR001412 aa-tRNA-synth_I_CS
    IPR002300 aa-tRNA-synth_Ia
    IPR033708 Anticodon_Ile_BEm
    IPR002301 Ile-tRNA-ligase
    IPR023585 Ile-tRNA-ligase_type1
    IPR013155 M/V/L/I-tRNA-synth_anticd-bd
    IPR014729 Rossmann-like_a/b/a_fold
    IPR009080 tRNAsynth_Ia_anticodon-bd
    IPR009008 Val/Leu/Ile-tRNA-synth_edit
    IPR010663 Znf_FPG/IleRS
    PfamiView protein in Pfam
    PF08264 Anticodon_1, 1 hit
    PF00133 tRNA-synt_1, 1 hit
    PF06827 zf-FPG_IleRS, 1 hit
    PRINTSiPR00984 TRNASYNTHILE
    SUPFAMiSSF47323 SSF47323, 1 hit
    SSF50677 SSF50677, 1 hit
    TIGRFAMsiTIGR00392 ileS, 1 hit
    PROSITEiView protein in PROSITE
    PS00178 AA_TRNA_LIGASE_I, 1 hit

    Sequencei

    Sequence statusi: Complete.

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

    P00956-1 [UniParc]FASTAAdd to basket
    « Hide
            10         20         30         40         50
    MSDYKSTLNL PETGFPMRGD LAKREPGMLA RWTDDDLYGI IRAAKKGKKT
    60 70 80 90 100
    FILHDGPPYA NGSIHIGHSV NKILKDIIVK SKGLSGYDSP YVPGWDCHGL
    110 120 130 140 150
    PIELKVEQEY GKPGEKFTAA EFRAKCREYA ATQVDGQRKD FIRLGVLGDW
    160 170 180 190 200
    SHPYLTMDFK TEANIIRALG KIIGNGHLHK GAKPVHWCVD CRSALAEAEV
    210 220 230 240 250
    EYYDKTSPSI DVAFQAVDQD ALKAKFAVSN VNGPISLVIW TTTPWTLPAN
    260 270 280 290 300
    RAISIAPDFD YALVQIDGQA VILAKDLVES VMQRIGVTDY TILGTVKGAE
    310 320 330 340 350
    LELLRFTHPF MGFDVPAILG DHVTLDAGTG AVHTAPGHGP DDYVIGQKYG
    360 370 380 390 400
    LETANPVGPD GTYLPGTYPT LDGVNVFKAN DIVVALLQEK GALLHVEKMQ
    410 420 430 440 450
    HSYPCCWRHK TPIIFRATPQ WFVSMDQKGL RAQSLKEIKG VQWIPDWGQA
    460 470 480 490 500
    RIESMVANRP DWCISRQRTW GVPMSLFVHK DTEELHPRTL ELMEEVAKRV
    510 520 530 540 550
    EVDGIQAWWD LDAKEILGDE ADQYVKVPDT LDVWFDSGST HSSVVDVRPE
    560 570 580 590 600
    FAGHAADMYL EGSDQHRGWF MSSLMISTAM KGKAPYRQVL THGFTVDGQG
    610 620 630 640 650
    RKMSKSIGNT VSPQDVMNKL GADILRLWVA STDYTGEMAV SDEILKRAAD
    660 670 680 690 700
    SYRRIRNTAR FLLANLNGFD PAKDMVKPEE MVVLDRWAVG CAKAAQEDIL
    710 720 730 740 750
    KAYEAYDFHE VVQRLMRFCS VEMGSFYLDI IKDRQYTAKA DSVARRSCQT
    760 770 780 790 800
    ALYHIAEALV RWMAPILSFT ADEVWGYLPG EREKYVFTGE WYEGLFGLAD
    810 820 830 840 850
    SEAMNDAFWD ELLKVRGEVN KVIEQARADK KVGGSLEAAV TLYAEPELSA
    860 870 880 890 900
    KLTALGDELR FVLLTSGATV ADYNDAPADA QQSEVLKGLK VALSKAEGEK
    910 920 930
    CPRCWHYTQD VGKVAEHAEI CGRCVSNVAG DGEKRKFA
    Length:938
    Mass (Da):104,297
    Last modified:January 23, 2007 - v5
    Checksum:i238CEDAF461F01D5
    GO

    Experimental Info

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Sequence conflicti243 – 264TPWTL…DYALV → RRGLCLPTAQSLLHQISTMR WW AA sequence (PubMed:6390679).CuratedAdd BLAST22
    Sequence conflicti300 – 301EL → DV AA sequence (PubMed:6390679).Curated2
    Sequence conflicti587R → C AA sequence (PubMed:6390679).Curated1
    Sequence conflicti637E → Q AA sequence (PubMed:6390679).Curated1
    Sequence conflicti724G → V AA sequence (PubMed:6390679).Curated1
    Sequence conflicti738A → P AA sequence (PubMed:6390679).Curated1
    Sequence conflicti740 – 743ADSV → RTVW AA sequence (PubMed:6390679).Curated4
    Sequence conflicti787F → L AA sequence (PubMed:6390679).Curated1
    Sequence conflicti830K → N AA sequence (PubMed:6390679).Curated1
    Sequence conflicti867 – 869GAT → DRRY AA sequence (PubMed:6390679).Curated3

    Natural variant

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Natural varianti594F → L in strain: PS102. 1

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    U00096 Genomic DNA Translation: AAC73137.1
    AP009048 Genomic DNA Translation: BAB96595.2
    M10428 Genomic DNA Translation: AAA24606.1
    X00776 Genomic DNA Translation: CAA25352.1
    K01990 Genomic DNA Translation: AAA24091.1
    PIRiB64723 SYECIT
    RefSeqiNP_414567.1, NC_000913.3
    WP_001286857.1, NZ_LN832404.1

    Genome annotation databases

    EnsemblBacteriaiAAC73137; AAC73137; b0026
    BAB96595; BAB96595; BAB96595
    GeneIDi944761
    KEGGiecj:JW0024
    eco:b0026
    PATRICifig|1411691.4.peg.2259

    Similar proteinsi

    Cross-referencesi

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    U00096 Genomic DNA Translation: AAC73137.1
    AP009048 Genomic DNA Translation: BAB96595.2
    M10428 Genomic DNA Translation: AAA24606.1
    X00776 Genomic DNA Translation: CAA25352.1
    K01990 Genomic DNA Translation: AAA24091.1
    PIRiB64723 SYECIT
    RefSeqiNP_414567.1, NC_000913.3
    WP_001286857.1, NZ_LN832404.1

    3D structure databases

    ProteinModelPortaliP00956
    ModBaseiSearch...
    MobiDBiSearch...

    Protein-protein interaction databases

    BioGridi4261375, 35 interactors
    849163, 1 interactor
    DIPiDIP-10017N
    IntActiP00956, 17 interactors
    STRINGi316385.ECDH10B_0027

    Chemistry databases

    BindingDBiP00956
    ChEMBLiCHEMBL3657

    PTM databases

    iPTMnetiP00956

    Proteomic databases

    EPDiP00956
    PaxDbiP00956
    PRIDEiP00956

    Protocols and materials databases

    Structural Biology KnowledgebaseSearch...

    Genome annotation databases

    EnsemblBacteriaiAAC73137; AAC73137; b0026
    BAB96595; BAB96595; BAB96595
    GeneIDi944761
    KEGGiecj:JW0024
    eco:b0026
    PATRICifig|1411691.4.peg.2259

    Organism-specific databases

    EchoBASEiEB0487
    EcoGeneiEG10492 ileS

    Phylogenomic databases

    eggNOGiENOG4105C07 Bacteria
    COG0060 LUCA
    HOGENOMiHOG000246402
    InParanoidiP00956
    KOiK01870
    PhylomeDBiP00956

    Enzyme and pathway databases

    BioCyciEcoCyc:ILES-MONOMER
    MetaCyc:ILES-MONOMER

    Miscellaneous databases

    PROiPR:P00956

    Family and domain databases

    CDDicd07960 Anticodon_Ia_Ile_BEm, 1 hit
    Gene3Di3.40.50.620, 1 hit
    3.90.740.10, 1 hit
    HAMAPiMF_02002 Ile_tRNA_synth_type1, 1 hit
    InterProiView protein in InterPro
    IPR001412 aa-tRNA-synth_I_CS
    IPR002300 aa-tRNA-synth_Ia
    IPR033708 Anticodon_Ile_BEm
    IPR002301 Ile-tRNA-ligase
    IPR023585 Ile-tRNA-ligase_type1
    IPR013155 M/V/L/I-tRNA-synth_anticd-bd
    IPR014729 Rossmann-like_a/b/a_fold
    IPR009080 tRNAsynth_Ia_anticodon-bd
    IPR009008 Val/Leu/Ile-tRNA-synth_edit
    IPR010663 Znf_FPG/IleRS
    PfamiView protein in Pfam
    PF08264 Anticodon_1, 1 hit
    PF00133 tRNA-synt_1, 1 hit
    PF06827 zf-FPG_IleRS, 1 hit
    PRINTSiPR00984 TRNASYNTHILE
    SUPFAMiSSF47323 SSF47323, 1 hit
    SSF50677 SSF50677, 1 hit
    TIGRFAMsiTIGR00392 ileS, 1 hit
    PROSITEiView protein in PROSITE
    PS00178 AA_TRNA_LIGASE_I, 1 hit
    ProtoNetiSearch...

    Entry informationi

    Entry nameiSYI_ECOLI
    AccessioniPrimary (citable) accession number: P00956
    Secondary accession number(s): P78038, Q59429
    Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 21, 1986
    Last sequence update: January 23, 2007
    Last modified: November 7, 2018
    This is version 184 of the entry and version 5 of the sequence. See complete history.
    Entry statusiReviewed (UniProtKB/Swiss-Prot)
    Annotation programProkaryotic Protein Annotation Program

    Miscellaneousi

    Keywords - Technical termi

    Complete proteome, Direct protein sequencing, Reference proteome

    Documents

    1. SIMILARITY comments
      Index of protein domains and families
    2. Aminoacyl-tRNA synthetases
      List of aminoacyl-tRNA synthetase entries
    3. Escherichia coli
      Escherichia coli (strain K12): entries and cross-references to EcoGene
    UniProt is an ELIXIR core data resource
    Main funding by: National Institutes of Health

    We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.

    Do not show this banner again