ID   AKH2_ARATH              Reviewed;         916 AA.
AC   O81852; Q3E9Y8;
DT   11-JUL-2006, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1998, sequence version 1.
DT   27-MAR-2024, entry version 159.
DE   RecName: Full=Bifunctional aspartokinase/homoserine dehydrogenase 2, chloroplastic;
DE            Short=AK-HD 2;
DE            Short=AK-HSDH 2;
DE   AltName: Full=Beta-aspartyl phosphate homoserine 2;
DE   Includes:
DE     RecName: Full=Aspartokinase;
DE              EC=2.7.2.4 {ECO:0000269|PubMed:16216875};
DE     AltName: Full=Aspartate kinase {ECO:0000303|PubMed:16216875};
DE   Includes:
DE     RecName: Full=Homoserine dehydrogenase {ECO:0000303|PubMed:16216875};
DE              EC=1.1.1.3 {ECO:0000269|PubMed:16216875};
DE   Flags: Precursor;
GN   Name=AKHSDH2; Synonyms=AK-HSDH II; OrderedLocusNames=At4g19710;
GN   ORFNames=T16H5.70;
OS   Arabidopsis thaliana (Mouse-ear cress).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   rosids; malvids; Brassicales; Brassicaceae; Camelineae; Arabidopsis.
OX   NCBI_TaxID=3702;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=cv. Columbia;
RX   PubMed=10617198; DOI=10.1038/47134;
RA   Mayer K.F.X., Schueller C., Wambutt R., Murphy G., Volckaert G., Pohl T.,
RA   Duesterhoeft A., Stiekema W., Entian K.-D., Terryn N., Harris B.,
RA   Ansorge W., Brandt P., Grivell L.A., Rieger M., Weichselgartner M.,
RA   de Simone V., Obermaier B., Mache R., Mueller M., Kreis M., Delseny M.,
RA   Puigdomenech P., Watson M., Schmidtheini T., Reichert B., Portetelle D.,
RA   Perez-Alonso M., Boutry M., Bancroft I., Vos P., Hoheisel J.,
RA   Zimmermann W., Wedler H., Ridley P., Langham S.-A., McCullagh B.,
RA   Bilham L., Robben J., van der Schueren J., Grymonprez B., Chuang Y.-J.,
RA   Vandenbussche F., Braeken M., Weltjens I., Voet M., Bastiaens I., Aert R.,
RA   Defoor E., Weitzenegger T., Bothe G., Ramsperger U., Hilbert H., Braun M.,
RA   Holzer E., Brandt A., Peters S., van Staveren M., Dirkse W., Mooijman P.,
RA   Klein Lankhorst R., Rose M., Hauf J., Koetter P., Berneiser S., Hempel S.,
RA   Feldpausch M., Lamberth S., Van den Daele H., De Keyser A., Buysshaert C.,
RA   Gielen J., Villarroel R., De Clercq R., van Montagu M., Rogers J.,
RA   Cronin A., Quail M.A., Bray-Allen S., Clark L., Doggett J., Hall S.,
RA   Kay M., Lennard N., McLay K., Mayes R., Pettett A., Rajandream M.A.,
RA   Lyne M., Benes V., Rechmann S., Borkova D., Bloecker H., Scharfe M.,
RA   Grimm M., Loehnert T.-H., Dose S., de Haan M., Maarse A.C., Schaefer M.,
RA   Mueller-Auer S., Gabel C., Fuchs M., Fartmann B., Granderath K., Dauner D.,
RA   Herzl A., Neumann S., Argiriou A., Vitale D., Liguori R., Piravandi E.,
RA   Massenet O., Quigley F., Clabauld G., Muendlein A., Felber R., Schnabl S.,
RA   Hiller R., Schmidt W., Lecharny A., Aubourg S., Chefdor F., Cooke R.,
RA   Berger C., Monfort A., Casacuberta E., Gibbons T., Weber N., Vandenbol M.,
RA   Bargues M., Terol J., Torres A., Perez-Perez A., Purnelle B., Bent E.,
RA   Johnson S., Tacon D., Jesse T., Heijnen L., Schwarz S., Scholler P.,
RA   Heber S., Francs P., Bielke C., Frishman D., Haase D., Lemcke K.,
RA   Mewes H.-W., Stocker S., Zaccaria P., Bevan M., Wilson R.K.,
RA   de la Bastide M., Habermann K., Parnell L., Dedhia N., Gnoj L., Schutz K.,
RA   Huang E., Spiegel L., Sekhon M., Murray J., Sheet P., Cordes M.,
RA   Abu-Threideh J., Stoneking T., Kalicki J., Graves T., Harmon G.,
RA   Edwards J., Latreille P., Courtney L., Cloud J., Abbott A., Scott K.,
RA   Johnson D., Minx P., Bentley D., Fulton B., Miller N., Greco T., Kemp K.,
RA   Kramer J., Fulton L., Mardis E., Dante M., Pepin K., Hillier L.W.,
RA   Nelson J., Spieth J., Ryan E., Andrews S., Geisel C., Layman D., Du H.,
RA   Ali J., Berghoff A., Jones K., Drone K., Cotton M., Joshu C., Antonoiu B.,
RA   Zidanic M., Strong C., Sun H., Lamar B., Yordan C., Ma P., Zhong J.,
RA   Preston R., Vil D., Shekher M., Matero A., Shah R., Swaby I.K.,
RA   O'Shaughnessy A., Rodriguez M., Hoffman J., Till S., Granat S., Shohdy N.,
RA   Hasegawa A., Hameed A., Lodhi M., Johnson A., Chen E., Marra M.A.,
RA   Martienssen R., McCombie W.R.;
RT   "Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana.";
RL   Nature 402:769-777(1999).
RN   [2]
RP   GENOME REANNOTATION.
RC   STRAIN=cv. Columbia;
RX   PubMed=27862469; DOI=10.1111/tpj.13415;
RA   Cheng C.Y., Krishnakumar V., Chan A.P., Thibaud-Nissen F., Schobel S.,
RA   Town C.D.;
RT   "Araport11: a complete reannotation of the Arabidopsis thaliana reference
RT   genome.";
RL   Plant J. 89:789-804(2017).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), BIOPHYSICOCHEMICAL PROPERTIES,
RP   CATALYTIC ACTIVITY, AND ACTIVITY REGULATION.
RX   PubMed=11812230; DOI=10.1006/prep.2001.1539;
RA   Paris S., Wessel P.M., Dumas R.;
RT   "Overproduction, purification, and characterization of recombinant
RT   bifunctional threonine-sensitive aspartate kinase-homoserine dehydrogenase
RT   from Arabidopsis thaliana.";
RL   Protein Expr. Purif. 24:105-110(2002).
RN   [4]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
RC   STRAIN=cv. Columbia;
RX   PubMed=14993207; DOI=10.1101/gr.1515604;
RA   Castelli V., Aury J.-M., Jaillon O., Wincker P., Clepet C., Menard M.,
RA   Cruaud C., Quetier F., Scarpelli C., Schaechter V., Temple G., Caboche M.,
RA   Weissenbach J., Salanoubat M.;
RT   "Whole genome sequence comparisons and 'full-length' cDNA sequences: a
RT   combined approach to evaluate and improve Arabidopsis genome annotation.";
RL   Genome Res. 14:406-413(2004).
RN   [5]
RP   ACTIVITY REGULATION, MUTAGENESIS OF ILE-441; GLN-443; ILE-522 AND GLN-524,
RP   AND CATALYTIC ACTIVITY.
RX   PubMed=12435751; DOI=10.1074/jbc.m207379200;
RA   Paris S., Viemon C., Curien G., Dumas R.;
RT   "Mechanism of control of Arabidopsis thaliana aspartate kinase-homoserine
RT   dehydrogenase by threonine.";
RL   J. Biol. Chem. 278:5361-5366(2003).
RN   [6]
RP   CATALYTIC ACTIVITY, ACTIVITY REGULATION, AND BIOPHYSICOCHEMICAL PROPERTIES.
RX   PubMed=16216875; DOI=10.1074/jbc.m509324200;
RA   Curien G., Ravanel S., Robert M., Dumas R.;
RT   "Identification of six novel allosteric effectors of Arabidopsis thaliana
RT   aspartate kinase-homoserine dehydrogenase isoforms. Physiological context
RT   sets the specificity.";
RL   J. Biol. Chem. 280:41178-41183(2005).
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=L-homoserine + NADP(+) = H(+) + L-aspartate 4-semialdehyde +
CC         NADPH; Xref=Rhea:RHEA:15761, ChEBI:CHEBI:15378, ChEBI:CHEBI:57476,
CC         ChEBI:CHEBI:57783, ChEBI:CHEBI:58349, ChEBI:CHEBI:537519; EC=1.1.1.3;
CC         Evidence={ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:15762;
CC         Evidence={ECO:0000269|PubMed:12435751};
CC       PhysiologicalDirection=right-to-left; Xref=Rhea:RHEA:15763;
CC         Evidence={ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:12435751,
CC         ECO:0000269|PubMed:16216875};
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=L-homoserine + NAD(+) = H(+) + L-aspartate 4-semialdehyde +
CC         NADH; Xref=Rhea:RHEA:15757, ChEBI:CHEBI:15378, ChEBI:CHEBI:57476,
CC         ChEBI:CHEBI:57540, ChEBI:CHEBI:57945, ChEBI:CHEBI:537519; EC=1.1.1.3;
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=ATP + L-aspartate = 4-phospho-L-aspartate + ADP;
CC         Xref=Rhea:RHEA:23776, ChEBI:CHEBI:29991, ChEBI:CHEBI:30616,
CC         ChEBI:CHEBI:57535, ChEBI:CHEBI:456216; EC=2.7.2.4;
CC         Evidence={ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:23777;
CC         Evidence={ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:12435751,
CC         ECO:0000269|PubMed:16216875};
CC   -!- ACTIVITY REGULATION: Threonine interaction with Gln-443 leads to
CC       inhibition of aspartate kinase activity and facilitates the binding of
CC       a second threonine on Gln-524, leading to a partial inhibition of
CC       homoserine dehydrogenase activity (25% of activity remaining at
CC       saturation with threonine). Homoserine dehydrogenase activity is also
CC       partially inhibited by cysteine (15% of activity remaining at
CC       saturation with cysteine). No synergy between threonine and cysteine
CC       for the inhibition. 13-fold activation of aspartate kinase activity by
CC       cysteine, isoleucine, valine, serine and alanine at 2.5 mM and 4-fold
CC       activation by leucine at 2.5 mM, but no activation of homoserine
CC       dehydrogenase activity. {ECO:0000269|PubMed:11812230,
CC       ECO:0000269|PubMed:12435751, ECO:0000269|PubMed:16216875}.
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       Kinetic parameters:
CC         KM=11.6 mM for aspartate for the aspartokinase activity (in the
CC         presence of 40 mM ATP) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         KM=6.15 mM for aspartate for the aspartokinase activity (at pH 8.0,
CC         in the presence of 200 uM NADPH and 20 mM ATP)
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         KM=1.5 mM for aspartate for the aspartokinase activity (at pH 8.0, in
CC         the presence of 200 uM NADPH, 20 mM ATP and a saturating
CC         concentration of alanine) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         KM=26.4 mM for aspartate for the aspartokinase activity (in the
CC         presence of 100 mM ATP and 0.5 mM threonine)
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         KM=5.5 mM for ATP for the aspartokinase activity (in the presence of
CC         50 mM aspartate) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         KM=2.2 mM for ATP for the aspartokinase activity (at pH 8.0, in the
CC         presence of 200 uM NADPH and 50 mM aspartate)
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         KM=0.42 mM for ATP for the aspartokinase activity (at pH 8.0, in the
CC         presence of 200 uM NADPH, 50 mM aspartate and a saturating
CC         concentration of alanine) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         KM=5.2 mM for homoserine for the reverse reaction of the homoserine
CC         dehydrogenase activity (in the presence of 1 mM NADP)
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         KM=1.4 mM for aspartate semialdehyde for the forward reaction of the
CC         homoserine dehydrogenase activity (in the presence of NADPH)
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         KM=311 uM for aspartate semialdehyde for the forward reaction of the
CC         homoserine dehydrogenase activity (at pH 8.0, in the presence of 150
CC         mM KCl and 200 uM NADPH) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         KM=24.5 mM for homoserine for the reverse reaction of the homoserine
CC         dehydrogenase activity (in the presence of 1 mM NADP and 60 mM
CC         threonine) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         KM=166.1 uM for NADP for the reverse reaction of the homoserine
CC         dehydrogenase activity (in the presence of 50 mM homoserine)
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         KM=676.1 uM for NADP for the reverse reaction of the homoserine
CC         dehydrogenase activity (in the presence of 100 mM homoserine and 60
CC         mM threonine) {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         Vmax=5.4 umol/min/mg enzyme toward aspartylhydroxamate for the
CC         aspartokinase activity {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC         Vmax=165 umol/min/mg enzyme toward aspartate semialdehyde for the
CC         forward reaction of the homoserine dehydrogenase activity
CC         {ECO:0000269|PubMed:11812230, ECO:0000269|PubMed:16216875};
CC         Vmax=18.8 umol/min/mg enzyme toward NADPH for the reverse reaction of
CC         the homoserine dehydrogenase activity {ECO:0000269|PubMed:11812230,
CC         ECO:0000269|PubMed:16216875};
CC   -!- PATHWAY: Amino-acid biosynthesis; L-lysine biosynthesis via DAP
CC       pathway; (S)-tetrahydrodipicolinate from L-aspartate: step 1/4.
CC   -!- PATHWAY: Amino-acid biosynthesis; L-methionine biosynthesis via de novo
CC       pathway; L-homoserine from L-aspartate: step 1/3.
CC   -!- PATHWAY: Amino-acid biosynthesis; L-methionine biosynthesis via de novo
CC       pathway; L-homoserine from L-aspartate: step 3/3.
CC   -!- PATHWAY: Amino-acid biosynthesis; L-threonine biosynthesis; L-threonine
CC       from L-aspartate: step 1/5.
CC   -!- PATHWAY: Amino-acid biosynthesis; L-threonine biosynthesis; L-threonine
CC       from L-aspartate: step 3/5.
CC   -!- SUBUNIT: Homo- or heterodimer. {ECO:0000305}.
CC   -!- SUBCELLULAR LOCATION: Plastid, chloroplast.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing; Named isoforms=2;
CC       Name=1;
CC         IsoId=O81852-1; Sequence=Displayed;
CC       Name=2;
CC         IsoId=O81852-2; Sequence=VSP_019798;
CC   -!- SIMILARITY: In the N-terminal section; belongs to the aspartokinase
CC       family. {ECO:0000305}.
CC   -!- SIMILARITY: In the C-terminal section; belongs to the homoserine
CC       dehydrogenase family. {ECO:0000305}.
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DR   EMBL; AL024486; CAA19688.1; -; Genomic_DNA.
DR   EMBL; AL161551; CAB78973.1; -; Genomic_DNA.
DR   EMBL; CP002687; AEE84219.1; -; Genomic_DNA.
DR   EMBL; CP002687; AEE84220.1; -; Genomic_DNA.
DR   EMBL; BX827863; -; NOT_ANNOTATED_CDS; mRNA.
DR   PIR; T04752; T04752.
DR   RefSeq; NP_193706.2; NM_118091.3. [O81852-2]
DR   RefSeq; NP_974576.1; NM_202847.3. [O81852-1]
DR   AlphaFoldDB; O81852; -.
DR   SMR; O81852; -.
DR   BioGRID; 13008; 1.
DR   STRING; 3702.O81852; -.
DR   iPTMnet; O81852; -.
DR   PaxDb; 3702-AT4G19710-2; -.
DR   ProteomicsDB; 245073; -. [O81852-1]
DR   EnsemblPlants; AT4G19710.1; AT4G19710.1; AT4G19710. [O81852-2]
DR   EnsemblPlants; AT4G19710.2; AT4G19710.2; AT4G19710. [O81852-1]
DR   GeneID; 827715; -.
DR   Gramene; AT4G19710.1; AT4G19710.1; AT4G19710. [O81852-2]
DR   Gramene; AT4G19710.2; AT4G19710.2; AT4G19710. [O81852-1]
DR   KEGG; ath:AT4G19710; -.
DR   Araport; AT4G19710; -.
DR   TAIR; AT4G19710; AK-HSDH II.
DR   eggNOG; ENOG502QQBK; Eukaryota.
DR   HOGENOM; CLU_009116_7_1_1; -.
DR   InParanoid; O81852; -.
DR   OMA; VTCNKIA; -.
DR   OrthoDB; 2608453at2759; -.
DR   PhylomeDB; O81852; -.
DR   SABIO-RK; O81852; -.
DR   UniPathway; UPA00034; UER00015.
DR   UniPathway; UPA00050; UER00063.
DR   UniPathway; UPA00050; UER00461.
DR   UniPathway; UPA00051; UER00462.
DR   UniPathway; UPA00051; UER00465.
DR   PRO; PR:O81852; -.
DR   Proteomes; UP000006548; Chromosome 4.
DR   ExpressionAtlas; O81852; baseline and differential.
DR   GO; GO:0009507; C:chloroplast; HDA:TAIR.
DR   GO; GO:0009570; C:chloroplast stroma; HDA:TAIR.
DR   GO; GO:0004072; F:aspartate kinase activity; IDA:TAIR.
DR   GO; GO:0005524; F:ATP binding; IEA:UniProtKB-KW.
DR   GO; GO:0004412; F:homoserine dehydrogenase activity; IDA:TAIR.
DR   GO; GO:0050661; F:NADP binding; IEA:InterPro.
DR   GO; GO:0009089; P:lysine biosynthetic process via diaminopimelate; IEA:UniProtKB-UniPathway.
DR   GO; GO:0009086; P:methionine biosynthetic process; IEA:UniProtKB-KW.
DR   GO; GO:0016310; P:phosphorylation; IEA:UniProtKB-KW.
DR   GO; GO:0009088; P:threonine biosynthetic process; IEA:UniProtKB-UniPathway.
DR   CDD; cd04257; AAK_AK-HSDH; 1.
DR   CDD; cd04921; ACT_AKi-HSDH-ThrA-like_1; 1.
DR   CDD; cd04922; ACT_AKi-HSDH-ThrA_2; 1.
DR   Gene3D; 3.40.1160.10; Acetylglutamate kinase-like; 1.
DR   Gene3D; 3.40.50.720; NAD(P)-binding Rossmann-like Domain; 1.
DR   Gene3D; 3.30.2130.10; VC0802-like; 1.
DR   InterPro; IPR036393; AceGlu_kinase-like_sf.
DR   InterPro; IPR045865; ACT-like_dom_sf.
DR   InterPro; IPR002912; ACT_dom.
DR   InterPro; IPR041743; AK-HSDH_N.
DR   InterPro; IPR001048; Asp/Glu/Uridylate_kinase.
DR   InterPro; IPR005106; Asp/hSer_DH_NAD-bd.
DR   InterPro; IPR001341; Asp_kinase.
DR   InterPro; IPR018042; Aspartate_kinase_CS.
DR   InterPro; IPR011147; Bifunc_aspartokin/hSer_DH.
DR   InterPro; IPR027795; CASTOR_ACT_dom.
DR   InterPro; IPR001342; HDH_cat.
DR   InterPro; IPR019811; HDH_CS.
DR   InterPro; IPR036291; NAD(P)-bd_dom_sf.
DR   NCBIfam; TIGR00657; asp_kinases; 1.
DR   PANTHER; PTHR43070; -; 1.
DR   PANTHER; PTHR43070:SF5; HOMOSERINE DEHYDROGENASE; 1.
DR   Pfam; PF00696; AA_kinase; 1.
DR   Pfam; PF13840; ACT_7; 1.
DR   Pfam; PF00742; Homoserine_dh; 1.
DR   Pfam; PF03447; NAD_binding_3; 1.
DR   SUPFAM; SSF55021; ACT-like; 2.
DR   SUPFAM; SSF53633; Carbamate kinase-like; 1.
DR   SUPFAM; SSF55347; Glyceraldehyde-3-phosphate dehydrogenase-like, C-terminal domain; 1.
DR   SUPFAM; SSF51735; NAD(P)-binding Rossmann-fold domains; 1.
DR   PROSITE; PS51671; ACT; 2.
DR   PROSITE; PS00324; ASPARTOKINASE; 1.
DR   PROSITE; PS01042; HOMOSER_DHGENASE; 1.
DR   Genevisible; O81852; AT.
PE   1: Evidence at protein level;
KW   Alternative splicing; Amino-acid biosynthesis; ATP-binding; Chloroplast;
KW   Kinase; Methionine biosynthesis; Multifunctional enzyme; NADP;
KW   Nucleotide-binding; Oxidoreductase; Plastid; Reference proteome; Repeat;
KW   Transferase; Transit peptide.
FT   TRANSIT         1..87
FT                   /note="Chloroplast"
FT                   /evidence="ECO:0000255"
FT   CHAIN           88..916
FT                   /note="Bifunctional aspartokinase/homoserine dehydrogenase
FT                   2, chloroplastic"
FT                   /id="PRO_0000245845"
FT   DOMAIN          412..487
FT                   /note="ACT 1"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01007"
FT   DOMAIN          493..570
FT                   /note="ACT 2"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01007"
FT   REGION          88..336
FT                   /note="Aspartokinase"
FT                   /evidence="ECO:0000250"
FT   REGION          337..562
FT                   /note="Interface"
FT                   /evidence="ECO:0000250"
FT   REGION          563..916
FT                   /note="Homoserine dehydrogenase"
FT                   /evidence="ECO:0000250"
FT   BINDING         564..569
FT                   /ligand="NADP(+)"
FT                   /ligand_id="ChEBI:CHEBI:58349"
FT                   /evidence="ECO:0000255"
FT   VAR_SEQ         837..916
FT                   /note="LRYVGVVDAVNQKGTVELRRYKKEHPFAQLAGSDNIIAFTTTRYKDHPLIVR
FT                   GPGAGAQVTAGGIFSDILRLASYLGAPS -> RLFTTNVFPFDQCDHILTIYICM (in
FT                   isoform 2)"
FT                   /evidence="ECO:0000305"
FT                   /id="VSP_019798"
FT   MUTAGEN         441
FT                   /note="I->A: Loss of threonine sensitivity for the
FT                   aspartokinase activity and decreased inhibition of
FT                   homoserine dehydrogenase activity by threonine."
FT                   /evidence="ECO:0000269|PubMed:12435751"
FT   MUTAGEN         443
FT                   /note="Q->A: Loss of threonine sensitivity for the
FT                   aspartokinase activity and decreased inhibition of
FT                   homoserine dehydrogenase activity by threonine."
FT                   /evidence="ECO:0000269|PubMed:12435751"
FT   MUTAGEN         522
FT                   /note="I->A: No effect on the inhibition of aspartokinase
FT                   activity by threonine, but decreased inhibition of
FT                   homoserine dehydrogenase activity by threonine."
FT                   /evidence="ECO:0000269|PubMed:12435751"
FT   MUTAGEN         524
FT                   /note="Q->A: No effect on the inhibition of aspartokinase
FT                   activity by threonine, but decreased inhibition of
FT                   homoserine dehydrogenase activity by threonine."
FT                   /evidence="ECO:0000269|PubMed:12435751"
SQ   SEQUENCE   916 AA;  100250 MW;  7ECD984DAFC97C4F CRC64;
     MATLKPSFTV SPPNSNPIRF GSFPPQCFLR VPKPRRLILP RFRKTTGGGG GLIRCELPDF
     HLSATATTVS GVSTVNLVDQ VQIPKGEMWS VHKFGGTCVG NSQRIRNVAE VIINDNSERK
     LVVVSAMSKV TDMMYDLIRK AQSRDDSYLS ALEAVLEKHR LTARDLLDGD DLASFLSHLH
     NDISNLKAML RAIYIAGHAS ESFSDFVAGH GELWSAQMLS YVVRKTGLEC KWMDTRDVLI
     VNPTSSNQVD PDFGESEKRL DKWFSLNPSK IIIATGFIAS TPQNIPTTLK RDGSDFSAAI
     MGALLRARQV TIWTDVDGVY SADPRKVNEA VILQTLSYQE AWEMSYFGAN VLHPRTIIPV
     MRYNIPIVIR NIFNLSAPGT IICQPPEDDY DLKLTTPVKG FATIDNLALI NVEGTGMAGV
     PGTASDIFGC VKDVGANVIM ISQASSEHSV CFAVPEKEVN AVSEALRSRF SEALQAGRLS
     QIEVIPNCSI LAAVGQKMAS TPGVSCTLFS ALAKANINVR AISQGCSEYN VTVVIKREDS
     VKALRAVHSR FFLSRTTLAM GIVGPGLIGA TLLDQLRDQA AVLKQEFNID LRVLGITGSK
     KMLLSDIGID LSRWRELLNE KGTEADLDKF TQQVHGNHFI PNSVVVDCTA DSAIASRYYD
     WLRKGIHVIT PNKKANSGPL DQYLKLRDLQ RKSYTHYFYE ATVGAGLPII STLRGLLETG
     DKILRIEGIC SGTLSYLFNN FVGDRSFSEV VTEAKNAGFT EPDPRDDLSG TDVARKVIIL
     ARESGLKLDL ADLPIRSLVP EPLKGCTSVE EFMEKLPQYD GDLAKERLDA ENSGEVLRYV
     GVVDAVNQKG TVELRRYKKE HPFAQLAGSD NIIAFTTTRY KDHPLIVRGP GAGAQVTAGG
     IFSDILRLAS YLGAPS
//