TKTC_MAIZE
ID TKTC_MAIZE Reviewed; 675 AA.
AC Q7SIC9;
DT 18-APR-2006, integrated into UniProtKB/Swiss-Prot.
DT 15-DEC-2003, sequence version 1.
DT 03-AUG-2022, entry version 97.
DE RecName: Full=Transketolase, chloroplastic;
DE Short=TK;
DE EC=2.2.1.1;
OS Zea mays (Maize).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; Liliopsida; Poales; Poaceae; PACMAD clade;
OC Panicoideae; Andropogonodae; Andropogoneae; Tripsacinae; Zea.
OX NCBI_TaxID=4577;
RN [1] {ECO:0000305, ECO:0000312|PDB:1ITZ}
RP NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 1-10, X-RAY CRYSTALLOGRAPHY
RP (2.3 ANGSTROMS) IN COMPLEX WITH COFACTOR, FUNCTION, CATALYTIC ACTIVITY,
RP SUBUNIT, BIOPHYSICOCHEMICAL PROPERTIES, AND MASS SPECTROMETRY.
RX PubMed=12913150; DOI=10.1104/pp.103.020982;
RA Gerhardt S., Echt S., Busch M., Freigang J., Auerbach G., Bader G.,
RA Martin W.F., Bacher A., Huber R., Fischer M.;
RT "Structure and properties of an engineered transketolase from maize.";
RL Plant Physiol. 132:1941-1949(2003).
CC -!- FUNCTION: Catalyzes the reversible transfer of a two-carbon ketol group
CC from fructose-6-phosphate or sedoheptulose-7-phosphate to
CC glyceraldehyde-3-phosphate to yield xylulose-5-phosphate and erythrose-
CC 4-phosphate or ribose-5-phosphate, respectively.
CC {ECO:0000269|PubMed:12913150}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=D-glyceraldehyde 3-phosphate + D-sedoheptulose 7-phosphate =
CC aldehydo-D-ribose 5-phosphate + D-xylulose 5-phosphate;
CC Xref=Rhea:RHEA:10508, ChEBI:CHEBI:57483, ChEBI:CHEBI:57737,
CC ChEBI:CHEBI:58273, ChEBI:CHEBI:59776; EC=2.2.1.1;
CC Evidence={ECO:0000269|PubMed:12913150};
CC -!- COFACTOR:
CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250};
CC Name=Ca(2+); Xref=ChEBI:CHEBI:29108; Evidence={ECO:0000250};
CC Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000250};
CC Name=Co(2+); Xref=ChEBI:CHEBI:48828; Evidence={ECO:0000250};
CC Note=Binds 1 Mg(2+) ion per subunit. Can also utilize other divalent
CC metal cations, such as Ca(2+), Mn(2+) and Co(2+). {ECO:0000250};
CC -!- COFACTOR:
CC Name=thiamine diphosphate; Xref=ChEBI:CHEBI:58937;
CC Evidence={ECO:0000269|PubMed:12913150};
CC Note=Binds 1 thiamine pyrophosphate per subunit.
CC {ECO:0000269|PubMed:12913150};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=581 uM for ribulose-5-phosphate {ECO:0000269|PubMed:12913150};
CC KM=403 uM for xyulose-5-phosphate {ECO:0000269|PubMed:12913150};
CC Vmax=25.3 umol/min/mg enzyme with ribulose-5-phosphate as substrate
CC {ECO:0000269|PubMed:12913150};
CC -!- PATHWAY: Carbohydrate biosynthesis; Calvin cycle.
CC -!- SUBUNIT: Homodimer. {ECO:0000269|PubMed:12913150}.
CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast thylakoid membrane
CC {ECO:0000250}.
CC -!- MASS SPECTROMETRY: Mass=72994.8; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:12913150};
CC -!- SIMILARITY: Belongs to the transketolase family.
CC {ECO:0000269|PubMed:12913150}.
CC -!- SEQUENCE CAUTION:
CC Sequence=AAN65341.1; Type=Erroneous initiation; Evidence={ECO:0000305};
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DR EMBL; AY148193; AAN65341.1; ALT_INIT; Other_DNA.
DR PDB; 1ITZ; X-ray; 2.30 A; A/B/C=1-675.
DR PDBsum; 1ITZ; -.
DR AlphaFoldDB; Q7SIC9; -.
DR SMR; Q7SIC9; -.
DR STRING; 4577.GRMZM2G033208_P01; -.
DR PaxDb; Q7SIC9; -.
DR PRIDE; Q7SIC9; -.
DR MaizeGDB; 320183; -.
DR eggNOG; KOG0523; Eukaryota.
DR SABIO-RK; Q7SIC9; -.
DR UniPathway; UPA00116; -.
DR EvolutionaryTrace; Q7SIC9; -.
DR Proteomes; UP000007305; Unplaced.
DR ExpressionAtlas; Q7SIC9; baseline and differential.
DR GO; GO:0009535; C:chloroplast thylakoid membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0005829; C:cytosol; IBA:GO_Central.
DR GO; GO:0005509; F:calcium ion binding; TAS:AgBase.
DR GO; GO:0050897; F:cobalt ion binding; TAS:AgBase.
DR GO; GO:0030145; F:manganese ion binding; TAS:AgBase.
DR GO; GO:0004802; F:transketolase activity; IDA:AgBase.
DR GO; GO:0006098; P:pentose-phosphate shunt; IBA:GO_Central.
DR GO; GO:0019253; P:reductive pentose-phosphate cycle; IEA:UniProtKB-UniPathway.
DR CDD; cd02012; TPP_TK; 1.
DR Gene3D; 3.40.50.920; -; 1.
DR InterPro; IPR029061; THDP-binding.
DR InterPro; IPR009014; Transketo_C/PFOR_II.
DR InterPro; IPR005475; Transketolase-like_Pyr-bd.
DR InterPro; IPR005478; Transketolase_bac-like.
DR InterPro; IPR033248; Transketolase_C.
DR InterPro; IPR033247; Transketolase_fam.
DR InterPro; IPR005474; Transketolase_N.
DR PANTHER; PTHR43522; PTHR43522; 1.
DR Pfam; PF02779; Transket_pyr; 1.
DR Pfam; PF02780; Transketolase_C; 1.
DR Pfam; PF00456; Transketolase_N; 1.
DR SMART; SM00861; Transket_pyr; 1.
DR SUPFAM; SSF52518; SSF52518; 2.
DR SUPFAM; SSF52922; SSF52922; 1.
DR TIGRFAMs; TIGR00232; tktlase_bact; 1.
DR PROSITE; PS00801; TRANSKETOLASE_1; 1.
PE 1: Evidence at protein level;
KW 3D-structure; Chloroplast; Direct protein sequencing; Magnesium; Membrane;
KW Metal-binding; Plastid; Reference proteome; Thiamine pyrophosphate;
KW Thylakoid; Transferase.
FT CHAIN 1..675
FT /note="Transketolase, chloroplastic"
FT /id="PRO_0000232420"
FT ACT_SITE 423
FT /note="Proton donor"
FT /evidence="ECO:0000250"
FT BINDING 78
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 127..129
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 168
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 169
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /evidence="ECO:0000250"
FT BINDING 173
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 198
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 198
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /evidence="ECO:0000250"
FT BINDING 200
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT BINDING 275
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 275
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 369
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 396
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 423
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /note="in homodimeric partner"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 450..453
FT /ligand="thiamine diphosphate"
FT /ligand_id="ChEBI:CHEBI:58937"
FT /note="in homodimeric partner"
FT /evidence="ECO:0000269|PubMed:12913150"
FT BINDING 474
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 482
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT BINDING 533
FT /ligand="substrate"
FT /evidence="ECO:0000250"
FT SITE 38
FT /note="Important for catalytic activity"
FT /evidence="ECO:0000250"
FT SITE 275
FT /note="Important for catalytic activity"
FT /evidence="ECO:0000250"
FT HELIX 13..34
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 40..55
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 71..76
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 77..79
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 80..90
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 97..100
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 101..104
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 116..118
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 131..150
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 162..166
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 168..172
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 174..185
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 191..197
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 199..201
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 206..208
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 214..220
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 224..229
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 231..233
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 235..247
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 253..258
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 261..264
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 266..270
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 272..274
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 281..291
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 302..308
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 311..332
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 334..345
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 352..355
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 368..382
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 386..392
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 394..397
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 423..434
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 441..447
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 448..450
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 451..464
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 469..473
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 477..479
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 484..486
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 491..496
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 497..500
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 502..504
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 509..521
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 527..531
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 544..547
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 550..556
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 564..569
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 571..573
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 574..586
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 591..595
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 599..603
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 607..613
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 621..624
FT /evidence="ECO:0007829|PDB:1ITZ"
FT TURN 630..632
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 633..636
FT /evidence="ECO:0007829|PDB:1ITZ"
FT STRAND 641..643
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 654..661
FT /evidence="ECO:0007829|PDB:1ITZ"
FT HELIX 665..672
FT /evidence="ECO:0007829|PDB:1ITZ"
SQ SEQUENCE 675 AA; 72993 MW; 3F356BC2D0396510 CRC64;
GAVETLQGKA ATGELLEKSV NTIRFLAIDA VEKANSGHPG LPMGCAPMGH VLYDEVMRYN
PKNPYWFNRD RFVLSAGHGC MLQYALLHLA GYDSVKEEDL KQFRQWGSRT PGHPENFETP
GVEVTTGPLG QGIANAVGLA LAEKHLAARF NKPDSEIVDH YTYVILGDGC QMEGIANEAC
SLAGHWGLGK LIAFYDDNHI SIDGDTEIAF TEDVSTRFEA LGWHTIWVKN GNTGYDDIRA
AIKEAKAVTD KPTLIKVTTT IGFGSPNKAN SYSVHGSALG AKEVEATRQN LGWPYDTFFV
PEDVKSHWSR HTPEGAALEA DWNAKFAEYE KKYADDAATL KSIITGELPT GWVDALPKYT
PESPGDATRN LSQQCLNALA NVVPGLIGGS ADLASSNMTL LKMFGDFQKD TAEERNVRFG
VREHGMGAIC NGIALHSPGF VPYCATFFVF TDYMRGAMRI SALSEAGVIY VMTHDSIGLG
EDGPTHQPIE HLVSFRAMPN ILMLRPADGN ETAGAYKVAV LNRKRPSILA LSRQKLPHLP
GTSIEGVEKG GYTISDNSTG NKPDLIVMGT GSELEIAAKA ADELRKEGKT VRVVSFVSWE
LFDEQSDEYK ESVLPAAVTA RISIEAGSTL GWQKYVGAQG KAIGIDKFGA SAPAGTIYKE
YGITVESIIA AAKSF
