ID FABH_STRPN Reviewed; 324 AA. AC P0A3C5; Q93NA1; Q9FBC7; DT 15-MAR-2005, integrated into UniProtKB/Swiss-Prot. DT 15-MAR-2005, sequence version 1. DT 27-MAR-2024, entry version 106. DE RecName: Full=Beta-ketoacyl-[acyl-carrier-protein] synthase III {ECO:0000255|HAMAP-Rule:MF_01815, ECO:0000303|PubMed:11375394}; DE Short=Beta-ketoacyl-ACP synthase III {ECO:0000255|HAMAP-Rule:MF_01815}; DE Short=KAS III {ECO:0000255|HAMAP-Rule:MF_01815}; DE EC=2.3.1.180 {ECO:0000255|HAMAP-Rule:MF_01815, ECO:0000269|PubMed:11375394}; DE EC=2.3.1.300 {ECO:0000269|PubMed:11375394}; DE AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase 3 {ECO:0000255|HAMAP-Rule:MF_01815}; DE AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase III {ECO:0000255|HAMAP-Rule:MF_01815}; DE AltName: Full=Branched-chain beta-ketoacyl-[acyl-carrier-protein] synthase {ECO:0000305}; DE AltName: Full=SpFabH; GN Name=fabH {ECO:0000303|PubMed:11375394}; OrderedLocusNames=SP_0417; OS Streptococcus pneumoniae serotype 4 (strain ATCC BAA-334 / TIGR4). OC Bacteria; Bacillota; Bacilli; Lactobacillales; Streptococcaceae; OC Streptococcus. OX NCBI_TaxID=170187; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, CATALYTIC ACTIVITY, SUBSTRATE RP SPECIFICITY, ACTIVITY REGULATION, BIOPHYSICOCHEMICAL PROPERTIES, AND RP SUBUNIT. RC STRAIN=ATCC BAA-334 / TIGR4; RX PubMed=11375394; DOI=10.1074/jbc.m101769200; RA Khandekar S.S., Gentry D.R., Van Aller G.S., Warren P., Xiang H., RA Silverman C., Doyle M.L., Chambers P.A., Konstantinidis A.K., Brandt M., RA Daines R.A., Lonsdale J.T.; RT "Identification, substrate specificity, and inhibition of the Streptococcus RT pneumoniae beta-ketoacyl-acyl carrier protein synthase III (FabH)."; RL J. Biol. Chem. 276:30024-30030(2001). RN [2] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=ATCC BAA-334 / TIGR4; RX PubMed=11463916; DOI=10.1126/science.1061217; RA Tettelin H., Nelson K.E., Paulsen I.T., Eisen J.A., Read T.D., RA Peterson S.N., Heidelberg J.F., DeBoy R.T., Haft D.H., Dodson R.J., RA Durkin A.S., Gwinn M.L., Kolonay J.F., Nelson W.C., Peterson J.D., RA Umayam L.A., White O., Salzberg S.L., Lewis M.R., Radune D., RA Holtzapple E.K., Khouri H.M., Wolf A.M., Utterback T.R., Hansen C.L., RA McDonald L.A., Feldblyum T.V., Angiuoli S.V., Dickinson T., Hickey E.K., RA Holt I.E., Loftus B.J., Yang F., Smith H.O., Venter J.C., Dougherty B.A., RA Morrison D.A., Hollingshead S.K., Fraser C.M.; RT "Complete genome sequence of a virulent isolate of Streptococcus RT pneumoniae."; RL Science 293:498-506(2001). CC -!- FUNCTION: Catalyzes the condensation reaction of fatty acid synthesis CC by the addition to an acyl acceptor of two carbons from malonyl-ACP. CC Catalyzes the first condensation reaction which initiates fatty acid CC synthesis and may therefore play a role in governing the total rate of CC fatty acid production. Possesses both acetoacetyl-ACP synthase and CC acetyl transacylase activities (PubMed:11375394). Utilizes short CC straight and branched-chain acyl-CoAs, with a preference for acetyl-CoA CC (PubMed:11375394). {ECO:0000269|PubMed:11375394}. CC -!- CATALYTIC ACTIVITY: CC Reaction=acetyl-CoA + H(+) + malonyl-[ACP] = 3-oxobutanoyl-[ACP] + CO2 CC + CoA; Xref=Rhea:RHEA:12080, Rhea:RHEA-COMP:9623, Rhea:RHEA- CC COMP:9625, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, ChEBI:CHEBI:57287, CC ChEBI:CHEBI:57288, ChEBI:CHEBI:78449, ChEBI:CHEBI:78450; CC EC=2.3.1.180; Evidence={ECO:0000255|HAMAP-Rule:MF_01815, CC ECO:0000269|PubMed:11375394}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:12081; CC Evidence={ECO:0000269|PubMed:11375394}; CC -!- CATALYTIC ACTIVITY: CC Reaction=butanoyl-CoA + H(+) + malonyl-[ACP] = 3-oxohexanoyl-[ACP] + CC CO2 + CoA; Xref=Rhea:RHEA:42248, Rhea:RHEA-COMP:9623, Rhea:RHEA- CC COMP:9629, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, ChEBI:CHEBI:57287, CC ChEBI:CHEBI:57371, ChEBI:CHEBI:78449, ChEBI:CHEBI:78456; CC Evidence={ECO:0000269|PubMed:11375394}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:42249; CC Evidence={ECO:0000269|PubMed:11375394}; CC -!- CATALYTIC ACTIVITY: CC Reaction=2-methylpropanoyl-CoA + H(+) + malonyl-[ACP] = 4-methyl-3- CC oxopentanoyl-[ACP] + CO2 + CoA; Xref=Rhea:RHEA:42268, Rhea:RHEA- CC COMP:9623, Rhea:RHEA-COMP:9940, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, CC ChEBI:CHEBI:57287, ChEBI:CHEBI:57338, ChEBI:CHEBI:78449, CC ChEBI:CHEBI:78820; EC=2.3.1.300; CC Evidence={ECO:0000269|PubMed:11375394}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:42269; CC Evidence={ECO:0000269|PubMed:11375394}; CC -!- CATALYTIC ACTIVITY: CC Reaction=3-methylbutanoyl-CoA + H(+) + malonyl-[ACP] = 5-methyl-3- CC oxohexanoyl-[ACP] + CO2 + CoA; Xref=Rhea:RHEA:42272, Rhea:RHEA- CC COMP:9623, Rhea:RHEA-COMP:9941, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, CC ChEBI:CHEBI:57287, ChEBI:CHEBI:57345, ChEBI:CHEBI:78449, CC ChEBI:CHEBI:78822; EC=2.3.1.300; CC Evidence={ECO:0000269|PubMed:11375394}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:42273; CC Evidence={ECO:0000269|PubMed:11375394}; CC -!- ACTIVITY REGULATION: Inhibited by the SB418011 antibiotic CC (PubMed:11375394). Not inhibited by cerulenin, and weakly inhibited by CC thiolactomycin (PubMed:11375394). {ECO:0000269|PubMed:11375394}. CC -!- BIOPHYSICOCHEMICAL PROPERTIES: CC Kinetic parameters: CC KM=40.3 uM for acetyl-CoA {ECO:0000269|PubMed:11375394}; CC KM=18.6 uM for malonyl-ACP {ECO:0000269|PubMed:11375394}; CC -!- PATHWAY: Lipid metabolism; fatty acid biosynthesis. {ECO:0000255|HAMAP- CC Rule:MF_01815}. CC -!- SUBUNIT: Homodimer. {ECO:0000255|HAMAP-Rule:MF_01815, CC ECO:0000269|PubMed:11375394}. CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_01815, CC ECO:0000305}. CC -!- DOMAIN: The last Arg residue of the ACP-binding site is essential for CC the weak association between ACP/AcpP and FabH. {ECO:0000255|HAMAP- CC Rule:MF_01815}. CC -!- SIMILARITY: Belongs to the thiolase-like superfamily. FabH family. CC {ECO:0000255|HAMAP-Rule:MF_01815, 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; AF384041; AAK91994.1; -; Genomic_DNA. DR EMBL; AE005672; AAK74580.1; -; Genomic_DNA. DR PIR; C95048; C95048. DR RefSeq; WP_000852948.1; NZ_CP089948.1. DR AlphaFoldDB; P0A3C5; -. DR SMR; P0A3C5; -. DR PaxDb; 170187-SP_0417; -. DR EnsemblBacteria; AAK74580; AAK74580; SP_0417. DR GeneID; 66805607; -. DR KEGG; spn:SP_0417; -. DR eggNOG; COG0332; Bacteria. DR PhylomeDB; P0A3C5; -. DR BioCyc; SPNE170187:G1FZB-432-MONOMER; -. DR BRENDA; 2.3.1.180; 1960. DR BRENDA; 2.3.1.41; 1960. DR UniPathway; UPA00094; -. DR Proteomes; UP000000585; Chromosome. DR GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell. DR GO; GO:0004315; F:3-oxoacyl-[acyl-carrier-protein] synthase activity; IEA:InterPro. DR GO; GO:0033818; F:beta-ketoacyl-acyl-carrier-protein synthase III activity; IEA:UniProtKB-UniRule. DR GO; GO:0006633; P:fatty acid biosynthetic process; IEA:UniProtKB-UniRule. DR CDD; cd00830; KAS_III; 1. DR Gene3D; 3.40.47.10; -; 1. DR HAMAP; MF_01815; FabH; 1. DR InterPro; IPR013747; ACP_syn_III_C. DR InterPro; IPR013751; ACP_syn_III_N. DR InterPro; IPR004655; FabH. DR InterPro; IPR016039; Thiolase-like. DR NCBIfam; TIGR00747; fabH; 1. DR PANTHER; PTHR43091; 3-OXOACYL-[ACYL-CARRIER-PROTEIN] SYNTHASE; 1. DR PANTHER; PTHR43091:SF1; 3-OXOACYL-[ACYL-CARRIER-PROTEIN] SYNTHASE III, CHLOROPLASTIC; 1. DR Pfam; PF08545; ACP_syn_III; 1. DR Pfam; PF08541; ACP_syn_III_C; 1. DR SUPFAM; SSF53901; Thiolase-like; 1. PE 1: Evidence at protein level; KW Acyltransferase; Cytoplasm; Fatty acid biosynthesis; Fatty acid metabolism; KW Lipid biosynthesis; Lipid metabolism; Multifunctional enzyme; KW Reference proteome; Transferase. FT CHAIN 1..324 FT /note="Beta-ketoacyl-[acyl-carrier-protein] synthase III" FT /id="PRO_0000110491" FT REGION 250..254 FT /note="ACP-binding" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01815" FT ACT_SITE 112 FT /evidence="ECO:0000255|HAMAP-Rule:MF_01815" FT ACT_SITE 249 FT /evidence="ECO:0000255|HAMAP-Rule:MF_01815" FT ACT_SITE 279 FT /evidence="ECO:0000255|HAMAP-Rule:MF_01815" FT CONFLICT 71 FT /note="E -> K (in Ref. 1; AAK91994)" FT /evidence="ECO:0000305" SQ SEQUENCE 324 AA; 34904 MW; 53E529125B392C70 CRC64; MAFAKISQVA HYVPEQVVTN HDLAQIMDTN DEWISSRTGI RQRHISRTES TSDLATEVAK KLMAKAGITG EELDFIILAT ITPDSMMPST AARVQANIGA NKAFAFDLTA ACSGFVFALS TAEKFIASGR FQKGLVIGSE TLSKAVDWSD RSTAVLFGDG AGGVLLEASE QEHFLAESLN SDGSRSECLT YGHSGLHSPF SDQESADSFL KMDGRTVFDF AIRDVAKSIK QTIDESPIEV TDLDYLLLHQ ANDRILDKMA RKIGVDRAKL PANMMEYGNT SAASIPILLS ECVEQGLIPL DGSQTVLLSG FGGGLTWGTL ILTI //