ID TKT_MYCLE Reviewed; 699 AA. AC P46708; DT 01-NOV-1995, integrated into UniProtKB/Swiss-Prot. DT 01-NOV-1995, sequence version 1. DT 10-JUN-2026, entry version 139. DE RecName: Full=Transketolase; DE Short=TK; DE EC=2.2.1.1 {ECO:0000269|PubMed:38767928}; GN Name=tkt; OrderedLocusNames=ML0583; ORFNames=B1496_F1_26, MLCL536.38; OS Mycobacterium leprae (strain TN). OC Bacteria; Bacillati; Actinomycetota; Actinomycetes; Mycobacteriales; OC Mycobacteriaceae; Mycobacterium. OX NCBI_TaxID=272631; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RA Smith D.R., Robison K.; RL Submitted (MAR-1994) to the EMBL/GenBank/DDBJ databases. RN [2] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=TN; RX PubMed=11234002; DOI=10.1038/35059006; RA Cole S.T., Eiglmeier K., Parkhill J., James K.D., Thomson N.R., RA Wheeler P.R., Honore N., Garnier T., Churcher C.M., Harris D.E., RA Mungall K.L., Basham D., Brown D., Chillingworth T., Connor R., RA Davies R.M., Devlin K., Duthoy S., Feltwell T., Fraser A., Hamlin N., RA Holroyd S., Hornsby T., Jagels K., Lacroix C., Maclean J., Moule S., RA Murphy L.D., Oliver K., Quail M.A., Rajandream M.A., Rutherford K.M., RA Rutter S., Seeger K., Simon S., Simmonds M., Skelton J., Squares R., RA Squares S., Stevens K., Taylor K., Whitehead S., Woodward J.R., RA Barrell B.G.; RT "Massive gene decay in the leprosy bacillus."; RL Nature 409:1007-1011(2001). RN [3] RP FUNCTION, CATALYTIC ACTIVITY, COFACTOR, AND ACTIVE SITE. RX PubMed=38767928; DOI=10.1021/acs.biochem.3c00714; RA Georges R.N., Ballut L., Aghajari N., Hecquet L., Charmantray F., RA Doumeche B.; RT "Biochemical, Bioinformatic, and Structural Comparisons of Transketolases RT and Position of Human Transketolase in the Enzyme Evolution."; RL Biochemistry 63:1460-1473(2024). CC -!- FUNCTION: Catalyzes the transfer of a two-carbon ketol group from a CC ketose donor to an aldose acceptor, via a covalent intermediate with CC the cofactor thiamine pyrophosphate (PubMed:38767928). Thus, catalyzes CC the reversible transfer of a two-carbon ketol group from sedoheptulose- CC 7-phosphate to glyceraldehyde-3-phosphate, producing xylulose-5- CC phosphate and ribose-5-phosphate (PubMed:38767928). CC {ECO:0000269|PubMed:38767928}. CC -!- CATALYTIC ACTIVITY: CC Reaction=D-sedoheptulose 7-phosphate + D-glyceraldehyde 3-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:38767928}; CC -!- COFACTOR: CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420; CC Evidence={ECO:0000269|PubMed:38767928}; CC Name=Ca(2+); Xref=ChEBI:CHEBI:29108; CC Evidence={ECO:0000250|UniProtKB:P27302}; CC Name=Mn(2+); Xref=ChEBI:CHEBI:29035; CC Evidence={ECO:0000250|UniProtKB:P27302}; CC Name=Co(2+); Xref=ChEBI:CHEBI:48828; CC Evidence={ECO:0000250|UniProtKB:P27302}; CC Note=Binds 1 Mg(2+) ion per subunit (PubMed:38767928). Can also utilize CC other divalent metal cations, such as Ca(2+), Mn(2+) and Co(2+). CC {ECO:0000250|UniProtKB:P27302, ECO:0000269|PubMed:38767928}; CC -!- COFACTOR: CC Name=thiamine diphosphate; Xref=ChEBI:CHEBI:58937; CC Evidence={ECO:0000305|PubMed:38767928}; CC Note=Binds 1 thiamine pyrophosphate per subunit. CC {ECO:0000250|UniProtKB:P9WG25}; CC -!- PATHWAY: Carbohydrate degradation; pentose phosphate pathway. CC {ECO:0000305}. CC -!- SUBUNIT: Homodimer. {ECO:0000250|UniProtKB:P9WG25}. CC -!- SIMILARITY: Belongs to the transketolase family. {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; U00013; AAA17139.1; -; Genomic_DNA. DR EMBL; Z99125; CAB16182.1; -; Genomic_DNA. DR EMBL; AL583919; CAC30091.1; -; Genomic_DNA. DR PIR; S72772; S72772. DR RefSeq; WP_010907818.1; NC_002677.1. DR AlphaFoldDB; P46708; -. DR SMR; P46708; -. DR STRING; 272631.gene:17574404; -. DR KEGG; mle:ML0583; -. DR PATRIC; fig|272631.5.peg.1017; -. DR Leproma; ML0583; -. DR eggNOG; COG0021; Bacteria. DR HOGENOM; CLU_009227_0_0_11; -. DR OrthoDB; 8732661at2; -. DR UniPathway; UPA00115; -. DR Proteomes; UP000000806; Chromosome. DR GO; GO:0005829; C:cytosol; IEA:TreeGrafter. DR GO; GO:0000287; F:magnesium ion binding; IEA:UniProtKB-ARBA. DR GO; GO:0004802; F:transketolase activity; IEA:UniProtKB-EC. DR GO; GO:0006098; P:pentose-phosphate shunt; IEA:TreeGrafter. DR CDD; cd07033; TPP_PYR_DXS_TK_like; 1. DR CDD; cd02012; TPP_TK; 1. DR FunFam; 3.40.50.920:FF:000003; Transketolase; 1. DR FunFam; 3.40.50.970:FF:000003; Transketolase; 1. DR FunFam; 3.40.50.970:FF:000004; Transketolase; 1. DR Gene3D; 3.40.50.920; -; 1. DR Gene3D; 3.40.50.970; -; 2. DR InterPro; IPR029061; THDP-binding. DR InterPro; IPR009014; Transketo_C/PFOR_II. DR InterPro; IPR055152; Transketolase-like_C_2. DR InterPro; IPR005475; Transketolase-like_Pyr-bd. DR InterPro; IPR005478; Transketolase_bac-like. DR InterPro; IPR020826; Transketolase_BS. DR InterPro; IPR049557; Transketolase_CS. DR InterPro; IPR033247; Transketolase_fam. DR InterPro; IPR005474; Transketolase_N. DR NCBIfam; TIGR00232; tktlase_bact; 1. DR PANTHER; PTHR43522; TRANSKETOLASE; 1. DR PANTHER; PTHR43522:SF2; TRANSKETOLASE 1-RELATED; 1. DR Pfam; PF02779; Transket_pyr; 1. DR Pfam; PF22613; Transketolase_C_1; 1. DR Pfam; PF00456; Transketolase_N; 1. DR SMART; SM00861; Transket_pyr; 1. DR SUPFAM; SSF52518; Thiamin diphosphate-binding fold (THDP-binding); 2. DR SUPFAM; SSF52922; TK C-terminal domain-like; 1. DR PROSITE; PS00801; TRANSKETOLASE_1; 1. DR PROSITE; PS00802; TRANSKETOLASE_2; 1. PE 1: Evidence at protein level; KW Calcium; Magnesium; Metal-binding; Reference proteome; KW Thiamine pyrophosphate; Transferase. FT CHAIN 1..699 FT /note="Transketolase" FT /id="PRO_0000191861" FT ACT_SITE 441 FT /note="Proton donor" FT /evidence="ECO:0000305|PubMed:38767928" FT BINDING 45 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 48 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 85 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 119 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 133 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 135 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 177 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 177 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 178 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 207 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 207 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 209 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 283 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 283 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 378 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 405 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 467 FT /ligand="thiamine diphosphate" FT /ligand_id="ChEBI:CHEBI:58937" FT /evidence="ECO:0000250|UniProtKB:P9WG25" FT BINDING 491 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 499 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 503 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT BINDING 552 FT /ligand="D-xylulose 5-phosphate" FT /ligand_id="ChEBI:CHEBI:57737" FT /ligand_label="(ligand shared between dimeric partners)" FT /evidence="ECO:0000250|UniProtKB:P27302" FT SITE 45 FT /note="Important for catalytic activity" FT /evidence="ECO:0000305|PubMed:38767928" FT SITE 283 FT /note="Important for catalytic activity" FT /evidence="ECO:0000305|PubMed:38767928" SQ SEQUENCE 699 AA; 75642 MW; 64900CFB9B4A4481 CRC64; MTTLDQISTL TQPRHPDDWT EIDSAAVDTI RVLATDAVQK AGNGHPGTAM SLAPLAYTLF QRTLRHDPND TAWLGRDRFV LSAGHSSLTL YIQLYLGGFG LELSDIESLR TWGSTTPGHP EFRHTKGVEI TTGPLGQGLA SAVGMAMASR YERGLFDPDA EPGASPFDHY IYVIASDGDI EEGVTSEASS LAAVQQLGNL IVFYDHNQIS IEGDTKITLC EDTAARYRAY GWHVQEVEGG ENVVGIEEAI ANAKAATDRP SFISLRTIIG YPAPTLINTG KAHGAALGED EVAATKRILG FDPDKTFAVR EDVITHTRGL IARGKEAHER WQLEFEAWAQ REPERKALLD RLLAQQLPDG WDADLPNWEP RSKELATRAA SGAVLSAIGP KLPELWGGSA DLAGSNNTTI KDVDSFGPPS ISTDEYTAHW YGRTLHFGVR EHAMGAILSG IVLHGPTRAY GGTFLQFSDY MRPSVRLASL MDIDTIYVWT HDSVGLGEDG PTHQPIEHLA ALRAIPRLSV VRPADANETA YAWRTILARG ANSGPVGLIL TRQSVPVLEG TNTEGVARGG YVLGDGGSSE AKEPDVILIA TGSEVQLAVA AQKLLADKDI IVRVVSMPCV EWFESQPYEY RDSVLPPSVS ARVAVEAGVA QCWHKLVGDT GKIVSIEHYG ESADYQTLFR EYGFTPEAVV AAAEQVLDN //