|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions → Protein-Modification Reactions|
|Reactions Classified By Substrate → Macromolecule Reactions → Protein-Reactions → Protein-Modification Reactions|
EC Number: 18.104.22.168
In Pathway: cis-vaccenate biosynthesis
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: β-ketoacyl-[acyl-carrier-protein] synthase II
Enzyme Commission Synonyms: KASII, KAS II, FabF, 3-oxoacyl-acyl carrier protein synthase I, β-ketoacyl-ACP synthase II, (Z)-hexadec-11-enoyl-[acyl-carrier-protein]:malonyl-[acyl-carrier-protein] C-acyltransferase (decarboxylating)
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): -9.277 [Latendresse13]
Enzyme Commission Summary:
Involved in the dissociated (or type II) fatty acid biosynthesis system that occurs in plants and bacteria. While the substrate specificity of this enzyme is very similar to that of EC 22.214.171.124, β-ketoacyl-ACP synthase I, it differs in that palmitoleoyl-ACP is not a good substrate of EC 126.96.36.199 but is an excellent substrate of this enzyme [DAgnolo75, Garwin80]. The fatty-acid composition of Escherichia coli changes as a function of growth temperature, with the proportion of unsaturated fatty acids increasing with lower growth temperature. This enzyme controls the temperature-dependent regulation of fatty-acid composition, with mutants lacking this acivity being deficient in the elongation of palmitoleate to cis-vaccenate at low temperatures [Price03, Garwin80a].
Cronan96: Cronan JE Jr., Rock CO (1996). "Biosynthesis of membrane lipids." In: Neidhardt, F.C. (Ed.), Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd edn, vol. 1, ASM Press, Washington, DC, pp. 612-636.
Garwin80: Garwin JL, Klages AL, Cronan JE (1980). "Structural, enzymatic, and genetic studies of beta-ketoacyl-acyl carrier protein synthases I and II of Escherichia coli." J Biol Chem 1980;255(24);11949-56. PMID: 7002930
Garwin80a: Garwin JL, Klages AL, Cronan JE (1980). "Beta-ketoacyl-acyl carrier protein synthase II of Escherichia coli. Evidence for function in the thermal regulation of fatty acid synthesis." J Biol Chem 1980;255(8);3263-5. PMID: 6988423
Price03: Price AC, Rock CO, White SW (2003). "The 1.3-Angstrom-resolution crystal structure of beta-ketoacyl-acyl carrier protein synthase II from Streptococcus pneumoniae." J Bacteriol 185(14);4136-43. PMID: 12837788
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