ID FABB_BUCAP Reviewed; 407 AA. AC Q8KA28; DT 08-NOV-2002, integrated into UniProtKB/Swiss-Prot. DT 01-OCT-2002, sequence version 1. DT 27-MAR-2024, entry version 111. DE RecName: Full=3-oxoacyl-[acyl-carrier-protein] synthase 1 {ECO:0000250|UniProtKB:P0A953}; DE EC=2.3.1.41 {ECO:0000250|UniProtKB:P0A953}; DE AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase I {ECO:0000250|UniProtKB:P0A953}; DE AltName: Full=Beta-ketoacyl-ACP synthase I {ECO:0000250|UniProtKB:P0A953}; DE Short=KAS I {ECO:0000250|UniProtKB:P0A953}; GN Name=fabB; OrderedLocusNames=BUsg_084; OS Buchnera aphidicola subsp. Schizaphis graminum (strain Sg). OC Bacteria; Pseudomonadota; Gammaproteobacteria; Enterobacterales; OC Erwiniaceae; Buchnera. OX NCBI_TaxID=198804; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=Sg; RX PubMed=12089438; DOI=10.1126/science.1071278; RA Tamas I., Klasson L., Canbaeck B., Naeslund A.K., Eriksson A.-S., RA Wernegreen J.J., Sandstroem J.P., Moran N.A., Andersson S.G.E.; RT "50 million years of genomic stasis in endosymbiotic bacteria."; RL Science 296:2376-2379(2002). CC -!- FUNCTION: Involved in the type II fatty acid elongation cycle. CC Catalyzes the elongation of a wide range of acyl-ACP by the addition of CC two carbons from malonyl-ACP to an acyl acceptor. Can also use CC unsaturated fatty acids. Catalyzes a key reaction in unsaturated fatty CC acid (UFA) synthesis, the elongation of the cis-3-decenoyl-ACP produced CC by FabA. {ECO:0000250|UniProtKB:P0A953}. CC -!- CATALYTIC ACTIVITY: CC Reaction=a fatty acyl-[ACP] + H(+) + malonyl-[ACP] = a 3-oxoacyl-[ACP] CC + CO2 + holo-[ACP]; Xref=Rhea:RHEA:22836, Rhea:RHEA-COMP:9623, CC Rhea:RHEA-COMP:9685, Rhea:RHEA-COMP:9916, Rhea:RHEA-COMP:14125, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, ChEBI:CHEBI:64479, CC ChEBI:CHEBI:78449, ChEBI:CHEBI:78776, ChEBI:CHEBI:138651; CC EC=2.3.1.41; Evidence={ECO:0000250|UniProtKB:P0A953}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:22837; CC Evidence={ECO:0000250|UniProtKB:P0A953}; CC -!- CATALYTIC ACTIVITY: CC Reaction=(3Z)-decenoyl-[ACP] + H(+) + malonyl-[ACP] = 3-oxo-(5Z)- CC dodecenoyl-[ACP] + CO2 + holo-[ACP]; Xref=Rhea:RHEA:54940, Rhea:RHEA- CC COMP:9623, Rhea:RHEA-COMP:9685, Rhea:RHEA-COMP:9927, Rhea:RHEA- CC COMP:14042, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526, ChEBI:CHEBI:64479, CC ChEBI:CHEBI:78449, ChEBI:CHEBI:78798, ChEBI:CHEBI:138410; CC Evidence={ECO:0000250|UniProtKB:P0A953}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:54941; CC Evidence={ECO:0000250|UniProtKB:P0A953}; CC -!- PATHWAY: Lipid metabolism; fatty acid biosynthesis. CC {ECO:0000250|UniProtKB:P0A953}. CC -!- SUBUNIT: Homodimer. {ECO:0000250|UniProtKB:P0A953}. CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000250|UniProtKB:P0A953}. CC -!- SIMILARITY: Belongs to the thiolase-like superfamily. Beta-ketoacyl-ACP CC synthases 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; AE013218; AAM67654.1; -; Genomic_DNA. DR RefSeq; WP_011053620.1; NC_004061.1. DR AlphaFoldDB; Q8KA28; -. DR SMR; Q8KA28; -. DR STRING; 198804.BUsg_084; -. DR GeneID; 75259041; -. DR KEGG; bas:BUsg_084; -. DR eggNOG; COG0304; Bacteria. DR HOGENOM; CLU_000022_69_2_6; -. DR UniPathway; UPA00094; -. DR Proteomes; UP000000416; Chromosome. DR GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell. DR GO; GO:0004315; F:3-oxoacyl-[acyl-carrier-protein] synthase activity; IEA:UniProtKB-EC. DR GO; GO:0006633; P:fatty acid biosynthetic process; IEA:UniProtKB-UniPathway. DR CDD; cd00834; KAS_I_II; 1. DR Gene3D; 3.40.47.10; -; 1. DR InterPro; IPR000794; Beta-ketoacyl_synthase. DR InterPro; IPR018201; Ketoacyl_synth_AS. DR InterPro; IPR014031; Ketoacyl_synth_C. DR InterPro; IPR014030; Ketoacyl_synth_N. DR InterPro; IPR020841; PKS_Beta-ketoAc_synthase_dom. DR InterPro; IPR016039; Thiolase-like. DR PANTHER; PTHR11712:SF306; 3-OXOACYL-[ACYL-CARRIER-PROTEIN] SYNTHASE 1; 1. DR PANTHER; PTHR11712; POLYKETIDE SYNTHASE-RELATED; 1. DR Pfam; PF00109; ketoacyl-synt; 1. DR Pfam; PF02801; Ketoacyl-synt_C; 1. DR SMART; SM00825; PKS_KS; 1. DR SUPFAM; SSF53901; Thiolase-like; 2. DR PROSITE; PS00606; KS3_1; 1. DR PROSITE; PS52004; KS3_2; 1. PE 3: Inferred from homology; KW Acyltransferase; Cytoplasm; Fatty acid biosynthesis; Fatty acid metabolism; KW Lipid biosynthesis; Lipid metabolism; Transferase. FT CHAIN 1..407 FT /note="3-oxoacyl-[acyl-carrier-protein] synthase 1" FT /id="PRO_0000180309" FT DOMAIN 1..406 FT /note="Ketosynthase family 3 (KS3)" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT ACT_SITE 164 FT /note="For beta-ketoacyl synthase activity" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT ACT_SITE 300 FT /note="For beta-ketoacyl synthase activity" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" FT ACT_SITE 336 FT /note="For beta-ketoacyl synthase activity" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01348" SQ SEQUENCE 407 AA; 44523 MW; CBCFC30445A34679 CRC64; MKRVVITGFG IISSIGNNKK EVLNSLYNGI SGITFSEEMK ESGMRSQVWG NIKLENKKFF KKNKISRFMN NGSIYAFLSM EQAIKDANLQ TKQYQKNPRI GIIAGSGGGF PKYHIQGIDA IRSNRGLNSV SPYIAIKAMN SGISACLSTL FKIYGVNYSI SSACATSGHC IGNAFELIKF GKQDLIFAGG GEEVSWELAY EFDAMKALSS NFNKNPTKSS RVYDVNRDGF VISGGGGIIV IEELNCALSR SAHIYAEIIG YAATSDGKDM VVPSGDGAVR CMNLAKKQNK MLFIDYLNVH GTSTKIGDLI ELEAIKKSFF HEKKPMISAT KSMTGHALGV SGVHEIIYTL LMMKYNFIAP SINIETIEPS ADNMNIVQKT FHKKIKTALS NSFGFGGTNV SLILKKY //