ID   PANB2_BURCH             Reviewed;         284 AA.
AC   A0AXR0;
DT   24-JUL-2007, integrated into UniProtKB/Swiss-Prot.
DT   28-NOV-2006, sequence version 1.
DT   28-JAN-2026, entry version 93.
DE   RecName: Full=3-methyl-2-oxobutanoate hydroxymethyltransferase 2 {ECO:0000255|HAMAP-Rule:MF_00156};
DE            EC=2.1.2.11 {ECO:0000255|HAMAP-Rule:MF_00156};
DE   AltName: Full=Ketopantoate hydroxymethyltransferase 2 {ECO:0000255|HAMAP-Rule:MF_00156};
DE            Short=KPHMT 2 {ECO:0000255|HAMAP-Rule:MF_00156};
GN   Name=panB2 {ECO:0000255|HAMAP-Rule:MF_00156};
GN   OrderedLocusNames=Bcen2424_3447;
OS   Burkholderia cenocepacia (strain HI2424).
OC   Bacteria; Pseudomonadati; Pseudomonadota; Betaproteobacteria;
OC   Burkholderiales; Burkholderiaceae; Burkholderia;
OC   Burkholderia cepacia complex.
OX   NCBI_TaxID=331272;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=HI2424;
RA   Copeland A., Lucas S., Lapidus A., Barry K., Detter J.C.,
RA   Glavina del Rio T., Hammon N., Israni S., Pitluck S., Chain P.,
RA   Malfatti S., Shin M., Vergez L., Schmutz J., Larimer F., Land M.,
RA   Hauser L., Kyrpides N., Kim E., LiPuma J.J., Gonzalez C.F.,
RA   Konstantinidis K., Tiedje J.M., Richardson P.;
RT   "Complete sequence of chromosome 2 of Burkholderia cenocepacia HI2424.";
RL   Submitted (AUG-2006) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Catalyzes the reversible reaction in which hydroxymethyl
CC       group from 5,10-methylenetetrahydrofolate is transferred onto alpha-
CC       ketoisovalerate to form ketopantoate. {ECO:0000255|HAMAP-
CC       Rule:MF_00156}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=(6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + 3-methyl-2-
CC         oxobutanoate + H2O = 2-dehydropantoate + (6S)-5,6,7,8-
CC         tetrahydrofolate; Xref=Rhea:RHEA:11824, ChEBI:CHEBI:11561,
CC         ChEBI:CHEBI:11851, ChEBI:CHEBI:15377, ChEBI:CHEBI:15636,
CC         ChEBI:CHEBI:57453; EC=2.1.2.11; Evidence={ECO:0000255|HAMAP-
CC         Rule:MF_00156};
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255|HAMAP-
CC         Rule:MF_00156};
CC       Note=Binds 1 Mg(2+) ion per subunit. {ECO:0000255|HAMAP-Rule:MF_00156};
CC   -!- PATHWAY: Cofactor biosynthesis; (R)-pantothenate biosynthesis; (R)-
CC       pantoate from 3-methyl-2-oxobutanoate: step 1/2. {ECO:0000255|HAMAP-
CC       Rule:MF_00156}.
CC   -!- SUBUNIT: Homodecamer; pentamer of dimers. {ECO:0000255|HAMAP-
CC       Rule:MF_00156}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_00156}.
CC   -!- SIMILARITY: Belongs to the PanB family. {ECO:0000255|HAMAP-
CC       Rule:MF_00156}.
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DR   EMBL; CP000459; ABK10186.1; -; Genomic_DNA.
DR   RefSeq; WP_011694497.1; NC_008543.1.
DR   AlphaFoldDB; A0AXR0; -.
DR   SMR; A0AXR0; -.
DR   KEGG; bch:Bcen2424_3447; -.
DR   HOGENOM; CLU_036645_1_0_4; -.
DR   UniPathway; UPA00028; UER00003.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0003864; F:3-methyl-2-oxobutanoate hydroxymethyltransferase activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0000287; F:magnesium ion binding; IEA:TreeGrafter.
DR   GO; GO:0015940; P:pantothenate biosynthetic process; IEA:UniProtKB-UniRule.
DR   CDD; cd06557; KPHMT-like; 1.
DR   FunFam; 3.20.20.60:FF:000003; 3-methyl-2-oxobutanoate hydroxymethyltransferase; 1.
DR   Gene3D; 3.20.20.60; Phosphoenolpyruvate-binding domains; 1.
DR   HAMAP; MF_00156; PanB; 1.
DR   InterPro; IPR003700; Pantoate_hydroxy_MeTrfase.
DR   InterPro; IPR015813; Pyrv/PenolPyrv_kinase-like_dom.
DR   InterPro; IPR040442; Pyrv_kinase-like_dom_sf.
DR   NCBIfam; TIGR00222; panB; 1.
DR   NCBIfam; NF001452; PRK00311.1; 1.
DR   PANTHER; PTHR20881; 3-METHYL-2-OXOBUTANOATE HYDROXYMETHYLTRANSFERASE; 1.
DR   PANTHER; PTHR20881:SF0; 3-METHYL-2-OXOBUTANOATE HYDROXYMETHYLTRANSFERASE; 1.
DR   Pfam; PF02548; Pantoate_transf; 1.
DR   PIRSF; PIRSF000388; Pantoate_hydroxy_MeTrfase; 1.
DR   SUPFAM; SSF51621; Phosphoenolpyruvate/pyruvate domain; 1.
PE   3: Inferred from homology;
KW   Cytoplasm; Magnesium; Metal-binding; Pantothenate biosynthesis;
KW   Transferase.
FT   CHAIN           1..284
FT                   /note="3-methyl-2-oxobutanoate hydroxymethyltransferase 2"
FT                   /id="PRO_0000297230"
FT   ACT_SITE        187
FT                   /note="Proton acceptor"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
FT   BINDING         49..50
FT                   /ligand="3-methyl-2-oxobutanoate"
FT                   /ligand_id="ChEBI:CHEBI:11851"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
FT   BINDING         49
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
FT   BINDING         88
FT                   /ligand="3-methyl-2-oxobutanoate"
FT                   /ligand_id="ChEBI:CHEBI:11851"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
FT   BINDING         88
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
FT   BINDING         118
FT                   /ligand="3-methyl-2-oxobutanoate"
FT                   /ligand_id="ChEBI:CHEBI:11851"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
FT   BINDING         120
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00156"
SQ   SEQUENCE   284 AA;  29919 MW;  1C27E26A77B57D16 CRC64;
     MSAHTRITRK TVTAIRSTKG IGSLVSLTAY SAPMAKLVDE VADVIIVGDS VGMVLYGMPD
     TLRVTLDMMI AHGAAVVRGA AQACVVVDLP FSTFQESPAQ AYRSAARLLA ETGAQAVKLE
     GGCEMTDTIR FLTDRGIPVM AHVGLMPQQA NAAGGFRAQG MDPRSAAQVF DAACAAERAG
     AFSVVIEGTA EALARHLTET LTIPTIGIGA SPACDGQVLV TEDMIGAFDA YTPRFVKRYA
     DANAVMRDAI RQYAHDVRQR VFPEPAHCFG YGKPLQLADA ATAA
//