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P0A817

- METK_ECOLI

UniProt

P0A817 - METK_ECOLI

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Protein

S-adenosylmethionine synthase

Gene

metK

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

Functioni

Catalyzes the formation of S-adenosylmethionine from methionine and ATP. The overall synthetic reaction is composed of two sequential steps, AdoMet formation and the subsequent tripolyphosphate hydrolysis which occurs prior to release of AdoMet from the enzyme. Is essential for growth.

Catalytic activityi

ATP + L-methionine + H2O = phosphate + diphosphate + S-adenosyl-L-methionine.

Cofactori

Binds 2 divalent ions per subunit. Magnesium or cobalt.
Binds 1 potassium ion per subunit.

Pathwayi

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Metal bindingi17 – 171Magnesium
Metal bindingi43 – 431Potassium
Binding sitei119 – 1191Methionine
Binding sitei239 – 2391Methionine
Metal bindingi264 – 2641Potassium
Metal bindingi272 – 2721Magnesium

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi260 – 2678ATPSequence Analysis

GO - Molecular functioni

  1. ATP binding Source: UniProtKB-HAMAP
  2. identical protein binding Source: IntAct
  3. magnesium ion binding Source: EcoCyc
  4. methionine adenosyltransferase activity Source: EcoCyc
  5. potassium ion binding Source: EcoCyc

GO - Biological processi

  1. one-carbon metabolic process Source: UniProtKB-HAMAP
  2. S-adenosylmethionine biosynthetic process Source: EcoCyc
  3. S-adenosylmethionine cycle Source: GO_Central
Complete GO annotation...

Keywords - Molecular functioni

Transferase

Keywords - Biological processi

One-carbon metabolism

Keywords - Ligandi

ATP-binding, Cobalt, Magnesium, Metal-binding, Nucleotide-binding, Potassium

Enzyme and pathway databases

BioCyciEcoCyc:S-ADENMETSYN-MONOMER.
ECOL316407:JW2909-MONOMER.
MetaCyc:S-ADENMETSYN-MONOMER.
SABIO-RKP0A817.
UniPathwayiUPA00315; UER00080.

Names & Taxonomyi

Protein namesi
Recommended name:
S-adenosylmethionine synthase (EC:2.5.1.6)
Short name:
AdoMet synthase
Alternative name(s):
MAT
Methionine adenosyltransferase
Gene namesi
Name:metK
Synonyms:metX
Ordered Locus Names:b2942, JW2909
OrganismiEscherichia coli (strain K12)
Taxonomic identifieri83333 [NCBI]
Taxonomic lineageiBacteriaProteobacteriaGammaproteobacteriaEnterobacterialesEnterobacteriaceaeEscherichia
ProteomesiUP000000318: Chromosome, UP000000625: Chromosome

Organism-specific databases

EcoGeneiEG10589. metK.

Subcellular locationi

GO - Cellular componenti

  1. cytosol Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm

Pathology & Biotechi

Disruption phenotypei

Cells are resistant to methionine-analogs, such as DL-ethionine(Et).1 Publication

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi15 – 151H → N: Loss of activity. 1 Publication
Mutagenesisi17 – 171D → N or A: Loss of activity. 1 Publication
Mutagenesisi43 – 431E → K: Misfolding and subject to proteolytic degradation. 1 Publication
Mutagenesisi43 – 431E → Q: Loss of stimulation by potassium. 1 Publication
Mutagenesisi90 – 901C → A or S: Decrease in the homotetramer formation capability. Enhanced thermal stability. 1 Publication
Mutagenesisi119 – 1191D → N: Decrease of both AdoMet synthesis and AdoMet-activated tripolyphosphate hydrolysis. 1 Publication
Mutagenesisi166 – 1661K → M: Decrease in AdoMet synthesis. 1 Publication
Mutagenesisi239 – 2391D → N: Decrease in AdoMet synthesis. 1 Publication
Mutagenesisi240 – 2401C → A: Decrease in AdoMet synthesis. 1 Publication
Mutagenesisi245 – 2451R → H or L: Loss of activity. 1 Publication
Mutagenesisi246 – 2461K → M: Loss of activity. modification in protein conformation. 1 Publication
Mutagenesisi266 – 2661K → A: Loss of activity. 1 Publication
Mutagenesisi266 – 2661K → M: Unstable; trace activity. 1 Publication
Mutagenesisi270 – 2701K → M: Decrease in activity. 1 Publication
Mutagenesisi272 – 2721D → N or A: Loss of activity. 1 Publication

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methioninei1 – 11Removed
Chaini2 – 384383S-adenosylmethionine synthasePRO_0000174518Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei3 – 31N6-acetyllysine1 Publication

Keywords - PTMi

Acetylation

Proteomic databases

PaxDbiP0A817.
PRIDEiP0A817.

2D gel databases

SWISS-2DPAGEP0A817.

PTM databases

PhosSiteiP0809415.

Expressioni

Inductioni

AdoMet activates the tripolyphosphatase reaction.

Gene expression databases

GenevestigatoriP0A817.

Interactioni

Subunit structurei

Homotetramer.

Binary interactionsi

WithEntry#Exp.IntActNotes
itself2EBI-546295,EBI-546295
groLP0A6F52EBI-546295,EBI-543750

Protein-protein interaction databases

DIPiDIP-35672N.
IntActiP0A817. 38 interactions.
MINTiMINT-1233798.
STRINGi511145.b2942.

Structurei

Secondary structure

1
384
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi4 – 118
Helixi16 – 3419
Beta strandi39 – 479
Beta strandi50 – 589
Helixi65 – 7612
Helixi81 – 833
Turni87 – 893
Beta strandi90 – 978
Helixi101 – 1077
Turni112 – 1143
Beta strandi117 – 1193
Beta strandi121 – 1288
Helixi137 – 15418
Beta strandi156 – 1583
Beta strandi161 – 17414
Beta strandi177 – 19014
Beta strandi192 – 1943
Helixi196 – 20611
Turni207 – 2115
Helixi214 – 2163
Beta strandi222 – 2265
Helixi235 – 2384
Beta strandi239 – 2424
Turni247 – 2548
Helixi271 – 28818
Beta strandi291 – 30111
Beta strandi309 – 3146
Beta strandi319 – 3213
Helixi323 – 33311
Helixi338 – 3458
Beta strandi348 – 3503
Helixi353 – 3564
Beta strandi360 – 3623
Beta strandi364 – 3663
Turni367 – 3693
Helixi373 – 3797
Turni380 – 3823

3D structure databases

Select the link destinations:
PDBe
RCSB PDB
PDBj
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1FUGX-ray3.20A/B2-384[»]
1MXAX-ray2.80A2-384[»]
1MXBX-ray2.80A2-384[»]
1MXCX-ray3.00A2-384[»]
1P7LX-ray2.50A/B/C/D2-384[»]
1RG9X-ray2.50A/B/C/D2-384[»]
1XRAX-ray3.00A2-384[»]
1XRBX-ray3.00A2-384[»]
1XRCX-ray3.00A2-384[»]
ProteinModelPortaliP0A817.
SMRiP0A817. Positions 2-384.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP0A817.

Family & Domainsi

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni239 – 24810Pyrophosphate binding

Sequence similaritiesi

Belongs to the AdoMet synthase family.Curated

Phylogenomic databases

eggNOGiCOG0192.
HOGENOMiHOG000245710.
InParanoidiP0A817.
KOiK00789.
OMAiGYVNSEM.
OrthoDBiEOG68WR6M.
PhylomeDBiP0A817.

Family and domain databases

HAMAPiMF_00086. S_AdoMet_synth1.
InterProiIPR022631. ADOMET_SYNTHASE_CS.
IPR022630. S-AdoMet_synt_C.
IPR022629. S-AdoMet_synt_central.
IPR022628. S-AdoMet_synt_N.
IPR002133. S-AdoMet_synthetase.
IPR022636. S-AdoMet_synthetase_sfam.
[Graphical view]
PANTHERiPTHR11964. PTHR11964. 1 hit.
PfamiPF02773. S-AdoMet_synt_C. 1 hit.
PF02772. S-AdoMet_synt_M. 1 hit.
PF00438. S-AdoMet_synt_N. 1 hit.
[Graphical view]
PIRSFiPIRSF000497. MAT. 1 hit.
SUPFAMiSSF55973. SSF55973. 3 hits.
TIGRFAMsiTIGR01034. metK. 1 hit.
PROSITEiPS00376. ADOMET_SYNTHASE_1. 1 hit.
PS00377. ADOMET_SYNTHASE_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

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

P0A817-1 [UniParc]FASTAAdd to Basket

« Hide

        10         20         30         40         50
MAKHLFTSES VSEGHPDKIA DQISDAVLDA ILEQDPKARV ACETYVKTGM
60 70 80 90 100
VLVGGEITTS AWVDIEEITR NTVREIGYVH SDMGFDANSC AVLSAIGKQS
110 120 130 140 150
PDINQGVDRA DPLEQGAGDQ GLMFGYATNE TDVLMPAPIT YAHRLVQRQA
160 170 180 190 200
EVRKNGTLPW LRPDAKSQVT FQYDDGKIVG IDAVVLSTQH SEEIDQKSLQ
210 220 230 240 250
EAVMEEIIKP ILPAEWLTSA TKFFINPTGR FVIGGPMGDC GLTGRKIIVD
260 270 280 290 300
TYGGMARHGG GAFSGKDPSK VDRSAAYAAR YVAKNIVAAG LADRCEIQVS
310 320 330 340 350
YAIGVAEPTS IMVETFGTEK VPSEQLTLLV REFFDLRPYG LIQMLDLLHP
360 370 380
IYKETAAYGH FGREHFPWEK TDKAQLLRDA AGLK
Length:384
Mass (Da):41,952
Last modified:January 23, 2007 - v2
Checksum:i97FA8CF17B542941
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti50 – 6112MVLVG…ITTSA → IGFSWRRNHHQRP(PubMed:6094561)CuratedAdd
BLAST
Sequence conflicti50 – 6112MVLVG…ITTSA → IGFSWRRNHHQRP(PubMed:2198270)CuratedAdd
BLAST
Sequence conflicti123 – 13311MFGYATNETDV → DVSATQLMKPTC in AAA24164. (PubMed:6094561)CuratedAdd
BLAST
Sequence conflicti159 – 1613PWL → RV(PubMed:6094561)Curated
Sequence conflicti159 – 1613PWL → RV(PubMed:8231813)Curated
Sequence conflicti172 – 1721Q → S in AAA24164. (PubMed:6094561)Curated
Sequence conflicti252 – 2521Y → T in AAA24164. (PubMed:6094561)Curated
Sequence conflicti305 – 3051V → L in AAA24164. (PubMed:6094561)Curated
Sequence conflicti337 – 3371Missing(PubMed:6094561)Curated
Sequence conflicti339 – 3391Y → I(PubMed:6094561)Curated
Sequence conflicti375 – 3762QL → HV(PubMed:8231813)Curated
Sequence conflicti378 – 3781R → P(PubMed:8231813)Curated

Mass spectrometryi

Molecular mass is 41843±10.5 Da from positions 2 - 384. Determined by ESI. 1 Publication

Sequence databases

Select the link destinations:
EMBL
GenBank
DDBJ
Links Updated
K02129 Genomic DNA. Translation: AAA24164.1.
U28377 Genomic DNA. Translation: AAA69109.1.
U00096 Genomic DNA. Translation: AAC75979.1.
AP009048 Genomic DNA. Translation: BAE77005.1.
M98266 Genomic DNA. Translation: AAB05197.1.
M31770 Genomic DNA. Translation: AAA24645.2.
PIRiE65079. SYECSM.
RefSeqiNP_417417.1. NC_000913.3.
YP_491141.1. NC_007779.1.

Genome annotation databases

EnsemblBacteriaiAAC75979; AAC75979; b2942.
BAE77005; BAE77005; BAE77005.
GeneIDi12931663.
945389.
KEGGiecj:Y75_p2872.
eco:b2942.
PATRICi32121294. VBIEscCol129921_3035.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBL
GenBank
DDBJ
Links Updated
K02129 Genomic DNA. Translation: AAA24164.1 .
U28377 Genomic DNA. Translation: AAA69109.1 .
U00096 Genomic DNA. Translation: AAC75979.1 .
AP009048 Genomic DNA. Translation: BAE77005.1 .
M98266 Genomic DNA. Translation: AAB05197.1 .
M31770 Genomic DNA. Translation: AAA24645.2 .
PIRi E65079. SYECSM.
RefSeqi NP_417417.1. NC_000913.3.
YP_491141.1. NC_007779.1.

3D structure databases

Select the link destinations:
PDBe
RCSB PDB
PDBj
Links Updated
Entry Method Resolution (Å) Chain Positions PDBsum
1FUG X-ray 3.20 A/B 2-384 [» ]
1MXA X-ray 2.80 A 2-384 [» ]
1MXB X-ray 2.80 A 2-384 [» ]
1MXC X-ray 3.00 A 2-384 [» ]
1P7L X-ray 2.50 A/B/C/D 2-384 [» ]
1RG9 X-ray 2.50 A/B/C/D 2-384 [» ]
1XRA X-ray 3.00 A 2-384 [» ]
1XRB X-ray 3.00 A 2-384 [» ]
1XRC X-ray 3.00 A 2-384 [» ]
ProteinModelPortali P0A817.
SMRi P0A817. Positions 2-384.
ModBasei Search...
MobiDBi Search...

Protein-protein interaction databases

DIPi DIP-35672N.
IntActi P0A817. 38 interactions.
MINTi MINT-1233798.
STRINGi 511145.b2942.

PTM databases

PhosSitei P0809415.

2D gel databases

SWISS-2DPAGE P0A817.

Proteomic databases

PaxDbi P0A817.
PRIDEi P0A817.

Protocols and materials databases

Structural Biology Knowledgebase Search...

Genome annotation databases

EnsemblBacteriai AAC75979 ; AAC75979 ; b2942 .
BAE77005 ; BAE77005 ; BAE77005 .
GeneIDi 12931663.
945389.
KEGGi ecj:Y75_p2872.
eco:b2942.
PATRICi 32121294. VBIEscCol129921_3035.

Organism-specific databases

EchoBASEi EB0584.
EcoGenei EG10589. metK.

Phylogenomic databases

eggNOGi COG0192.
HOGENOMi HOG000245710.
InParanoidi P0A817.
KOi K00789.
OMAi GYVNSEM.
OrthoDBi EOG68WR6M.
PhylomeDBi P0A817.

Enzyme and pathway databases

UniPathwayi UPA00315 ; UER00080 .
BioCyci EcoCyc:S-ADENMETSYN-MONOMER.
ECOL316407:JW2909-MONOMER.
MetaCyc:S-ADENMETSYN-MONOMER.
SABIO-RK P0A817.

Miscellaneous databases

EvolutionaryTracei P0A817.
PROi P0A817.

Gene expression databases

Genevestigatori P0A817.

Family and domain databases

HAMAPi MF_00086. S_AdoMet_synth1.
InterProi IPR022631. ADOMET_SYNTHASE_CS.
IPR022630. S-AdoMet_synt_C.
IPR022629. S-AdoMet_synt_central.
IPR022628. S-AdoMet_synt_N.
IPR002133. S-AdoMet_synthetase.
IPR022636. S-AdoMet_synthetase_sfam.
[Graphical view ]
PANTHERi PTHR11964. PTHR11964. 1 hit.
Pfami PF02773. S-AdoMet_synt_C. 1 hit.
PF02772. S-AdoMet_synt_M. 1 hit.
PF00438. S-AdoMet_synt_N. 1 hit.
[Graphical view ]
PIRSFi PIRSF000497. MAT. 1 hit.
SUPFAMi SSF55973. SSF55973. 3 hits.
TIGRFAMsi TIGR01034. metK. 1 hit.
PROSITEi PS00376. ADOMET_SYNTHASE_1. 1 hit.
PS00377. ADOMET_SYNTHASE_2. 1 hit.
[Graphical view ]
ProtoNeti Search...

Publicationsi

« Hide 'large scale' publications
  1. "The sequence of metK, the structural gene for S-adenosylmethionine synthetase in Escherichia coli."
    Markham G.D., Deparasis J., Gatmaitan J.
    J. Biol. Chem. 259:14505-14507(1984) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
  2. "Isozymes of S-adenosylmethionine synthetase are encoded by tandemly duplicated genes in Escherichia coli."
    Satishchandran C., Taylor J.C., Markham G.D.
    Mol. Microbiol. 9:835-846(1993) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], DISRUPTION PHENOTYPE.
    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. "Nucleotide sequence and analysis of the speA gene encoding biosynthetic arginine decarboxylase in Escherichia coli."
    Moore R.C., Boyle S.M.
    J. Bacteriol. 172:4631-4640(1990) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 1-63.
  6. "Investigation of monovalent cation activation of S-adenosylmethionine synthetase using mutagenesis and uranyl inhibition."
    McQueney M.S., Markham G.D.
    J. Biol. Chem. 270:18277-18284(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS OF GLU-43.
  7. "Structural and functional roles of cysteine 90 and cysteine 240 in S-adenosylmethionine synthetase."
    Reczkowski R.S., Markham G.D.
    J. Biol. Chem. 270:18484-18490(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS OF CYS-90 AND CYS-240.
    Strain: B and K12.
  8. "Escherichia coli proteome analysis using the gene-protein database."
    VanBogelen R.A., Abshire K.Z., Moldover B., Olson E.R., Neidhardt F.C.
    Electrophoresis 18:1243-1251(1997) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY 2D-GEL.
  9. "The active-site arginine of S-adenosylmethionine synthetase orients the reaction intermediate."
    Reczkowski R.S., Taylor J.C., Markham G.D.
    Biochemistry 37:13499-13506(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS OF ARG-245.
    Strain: B and K12.
  10. "The bifunctional active site of S-adenosylmethionine synthetase. Roles of the active site aspartates."
    Taylor J.C., Markham G.D.
    J. Biol. Chem. 274:32909-32914(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS OF ASP-17; ASP-119; ASP-239 AND ASP-272.
    Strain: B and K12.
  11. "The bifunctional active site of S-adenosylmethionine synthetase. Roles of the basic residues."
    Taylor J.C., Markham G.D.
    J. Biol. Chem. 275:4060-4065(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: MUTAGENESIS OF HIS-15; LYS-166; LYS-246; LYS-266 AND LYS-270.
    Strain: B and K12.
  12. "Studies on the role of the metK gene product of Escherichia coli K-12."
    Wei Y., Newman E.B.
    Mol. Microbiol. 43:1651-1656(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: TRANSCRIPTIONAL START SITE, ESSENTIAL GENE.
  13. "Lysine acetylation is a highly abundant and evolutionarily conserved modification in Escherichia coli."
    Zhang J., Sprung R., Pei J., Tan X., Kim S., Zhu H., Liu C.F., Grishin N.V., Zhao Y.
    Mol. Cell. Proteomics 8:215-225(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT LYS-3, IDENTIFICATION BY MASS SPECTROMETRY.
    Strain: K12 / JW1106 and K12 / MG1655 / ATCC 47076.
  14. "Crystal structure of S-adenosylmethionine synthetase."
    Takusagawa F., Kamitori S., Misaki S., Markham G.D.
    J. Biol. Chem. 271:136-147(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS), MASS SPECTROMETRY.
  15. "Structure and function of S-adenosylmethionine synthetase: crystal structures of S-adenosylmethionine synthetase with ADP, BrADP, and PPi at 2.8-A resolution."
    Takusagawa F., Kamitori S., Markham G.D.
    Biochemistry 35:2586-2596(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS).
  16. "Flexible loop in the structure of S-adenosylmethionine synthetase crystallized in the tetragonal modification."
    Fu Z., Hu Y., Markham G.D., Takusagawa F.
    J. Biomol. Struct. Dyn. 13:727-739(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (3.2 ANGSTROMS).

Entry informationi

Entry nameiMETK_ECOLI
AccessioniPrimary (citable) accession number: P0A817
Secondary accession number(s): P04384, P30869, Q2M9Q1
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 20, 1987
Last sequence update: January 23, 2007
Last modified: October 29, 2014
This is version 101 of the entry and version 2 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Miscellaneousi

Caution

Was originally thought to differ from MetX, which was assigned as a second AdoMet synthase before being shown to be identical to MetK.1 Publication

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Escherichia coli
    Escherichia coli (strain K12): entries and cross-references to EcoGene
  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