AC   MF_01815;
DC   Protein; auto
TR   HAMAP; MF_01815; -; 1; level=0
XX
Names: FabH
XX
case not <OC:Mycobacterium>
ID   FABH
DE   RecName: Full=Beta-ketoacyl-[acyl-carrier-protein] synthase III;
DE            Short=Beta-ketoacyl-ACP synthase III;
DE            Short=KAS III;
DE            EC=2.3.1.180;
DE   AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase 3;
DE   AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase III;
GN   Name=fabH;
else case <OC:Mycobacterium>
ID   FABH
DE   RecName: Full=Mycobacterial beta-ketoacyl-[acyl-carrier-protein] synthase III;
DE            Short=Beta-ketoacyl-ACP synthase III;
DE            Short=KAS III;
DE            EC=2.3.1.301;
DE   AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase 3;
DE   AltName: Full=3-oxoacyl-[acyl-carrier-protein] synthase III;
GN   Name=fabH;
end case
XX
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. Its substrate specificity determines
CC       the biosynthesis of branched-chain and/or straight-chain of fatty
CC       acids.
case not <OC:Mycobacterium>
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;
else case <OC:Mycobacterium>
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=dodecanoyl-CoA + H(+) + malonyl-[ACP] = 3-oxotetradecanoyl-
CC         [ACP] + CO2 + CoA; Xref=Rhea:RHEA:43640, Rhea:RHEA-COMP:9623,
CC         Rhea:RHEA-COMP:9645, ChEBI:CHEBI:15378, ChEBI:CHEBI:16526,
CC         ChEBI:CHEBI:57287, ChEBI:CHEBI:57375, ChEBI:CHEBI:78449,
CC         ChEBI:CHEBI:78473; EC=2.3.1.301;
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:43641;
end case
CC   -!- PATHWAY: Lipid metabolism; fatty acid biosynthesis.
case <OC:Mycobacterium>
CC   -!- PATHWAY: Lipid metabolism; mycolic acid biosynthesis.
end case
CC   -!- SUBUNIT: Homodimer.
case <OG:Chloroplast>
CC   -!- SUBCELLULAR LOCATION: Plastid, chloroplast.
end case
case not <OG:Chloroplast>
CC   -!- SUBCELLULAR LOCATION: Cytoplasm.
end case
CC   -!- DOMAIN: The last Arg residue of the ACP-binding site is essential for
CC       the weak association between ACP/AcpP and FabH.
CC   -!- SIMILARITY: Belongs to the thiolase-like superfamily. FabH family.
XX
DR   NCBIfam; TIGR00747; FabH; 1; trigger=no
XX
KW   Acyltransferase
case not <OG:Chloroplast>
KW   Cytoplasm
end case
KW   Fatty acid biosynthesis
KW   Fatty acid metabolism
KW   Lipid biosynthesis
KW   Lipid metabolism
KW   Multifunctional enzyme
KW   Transferase
XX
GO   GO:0033818; F:beta-ketoacyl-acyl-carrier-protein synthase III activity
GO   GO:0006633; P:fatty acid biosynthetic process
case <OG:Chloroplast>
GO   GO:0009507; C:chloroplast
end case
case not <OG:Chloroplast>
GO   GO:0005737; C:cytoplasm
end case
XX
FT   From: FABH_ECOLI (P0A6R0)
FT   ACT_SITE        112
FT   Condition: C
FT   ACT_SITE        244
FT   Condition: H
FT   ACT_SITE        274
FT   Condition: N
FT   REGION          245..249
FT                   /note="ACP-binding"
FT   Condition: [QS]-[AP]-N-x-R
XX
Size: 309-364;
Related: None;
Template: P0A6R0; O34746; O07600; P0A3C5; Q54206; Q4URQ0; C0LNR0; P9WNG3; P68795; Q9F6D4;
Scope:
 Bacteria
 Plastid
Fusion:
 Nter: None
 Cter: None
Duplicate: in BACAN, HALH5, BACSU, BACTN, DEIRA, LACPL, STAES, STRAW, STRCO,
 VIBCH, VIBPA, VIBVU
Plasmid: in STAES, STRCO
Comments: In many organisms this enzyme can accept branched-chain acyl-CoAs
 (EC 2.3.1.300) in addition to acetyl-CoA. Mycobacterial enzyme acts on medium-
 and long-chain acyl-CoAs (EC 2.3.1.301) and has no activity with acetyl-CoA or
 branched-chain acyl-CoAs.
XX
# Revision 1.43 2023/06/01
//