MetaCyc Reaction:

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:

Enzymes and Genes:
fatty acid synthase Inferred by computational analysis : fas ( Mycobacterium tuberculosis H37Rv )
enoyl-[acyl-carrier-protein] reductase [NADH], chloroplastic Inferred from experiment : enrA1 ( Brassica napus )
enoyl-[acyl-carrier-protein] reductase (NADH) : fabV ( Vibrio albensis )
enoyl-[acyl-carrier-protein] reductase (NADH) : fabK ( Streptococcus pneumoniae )
enoyl-[acyl-carrier-protein] reductase Inferred from experiment : fabI ( Escherichia coli K-12 substr. MG1655 )

In Pathway: palmitate biosynthesis II (bacteria and plants)

Note that this reaction equation differs from the official Enzyme Commission reaction equation for this EC number, which can be found here .

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.

Direct generic reaction:
a 2,3,4-saturated fatty acyl-[acp] + NAD+ ← a trans-2-enoyl-[acyl-carrier protein] + NADH + H+ (

Enzyme Commission Primary Name: enoyl-[acyl-carrier-protein] reductase (NADH)

Enzyme Commission Synonyms: enoyl-[acyl carrier protein] reductase, enoyl-ACP reductase, NADH-enoyl acyl carrier protein reductase, NADH-specific enoyl-ACP reductase, acyl-[acyl-carrier-protein]:NAD+ oxidoreductase, fabI (gene name), inhA (gene name)

Standard Gibbs Free Energy (ΔrG in kcal/mol): 34.414032 Inferred by computational analysis [Latendresse13]

Enzyme Commission Summary:
The enzyme catalyses an essential step in fatty acid biosynthesis, the reduction of the 2,3-double bond in enoyl-acyl-[acyl-carrier-protein] derivatives of the elongating fatty acid moiety. The enzyme from the bacterium Escherichia coli accepts substrates with carbon chain length from 4 to 18 [Yu11a]. The enzyme from the bacterium Mycobacterium tuberculosis prefers substrates with carbon chain length from 12-24 carbons [Quemard95, Rozwarski99].

Citations: [Shimakata82, Weeks68]

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

Instance reaction of [a 2,3,4-saturated fatty acyl-[acp] + NAD+ ← a trans-2-enoyl-[acyl-carrier protein] + NADH + H+] (
i1: a decanoyl-[acp] + NAD+ ← a trans2-decenoyl-[acp] + NADH + H+ (

Relationship Links: BRENDA:EC: , ENZYME:EC: , IUBMB-ExplorEnz:EC:


Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Quemard95: Quemard A, Sacchettini JC, Dessen A, Vilcheze C, Bittman R, Jacobs WR, Blanchard JS (1995). "Enzymatic characterization of the target for isoniazid in Mycobacterium tuberculosis." Biochemistry 34(26);8235-41. PMID: 7599116

Rozwarski99: Rozwarski DA, Vilcheze C, Sugantino M, Bittman R, Sacchettini JC (1999). "Crystal structure of the Mycobacterium tuberculosis enoyl-ACP reductase, InhA, in complex with NAD+ and a C16 fatty acyl substrate." J Biol Chem 274(22);15582-9. PMID: 10336454

Shimakata82: Shimakata T, Stumpf PK (1982). "Purification and characterizations of beta-Ketoacyl-[acyl-carrier-protein] reductase, beta-hydroxyacyl-[acyl-carrier-protein] dehydrase, and enoyl-[acyl-carrier-protein] reductase from Spinacia oleracea leaves." Arch Biochem Biophys 218(1);77-91. PMID: 6756317

Weeks68: Weeks G, Wakil SJ (1968). "Studies on the mechanism of fatty acid synthesis. 18. Preparation and general properties of the enoyl acyl carrier protein reductases from Escherichia coli." J Biol Chem 1968;243(6);1180-9. PMID: 4384650

Yu11a: Yu X, Liu T, Zhu F, Khosla C (2011). "In vitro reconstitution and steady-state analysis of the fatty acid synthase from Escherichia coli." Proc Natl Acad Sci U S A 108(46);18643-8. PMID: 22042840

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 19.0 on Sat Mar 28, 2015, biocyc12.