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MetaCyc Pathway: fatty acid β-oxidation I
Inferred from experiment

Enzyme View:

Pathway diagram: fatty acid beta-oxidation I

Note: a dashed line (without arrowheads) between two compound names is meant to imply that the two names are just different instantiations of the same compound -- i.e. one may be a specific name and the other a general name, or they may both represent the same compound in different stages of a polymerization-type pathway. This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.

Superclasses: Degradation/Utilization/AssimilationFatty Acid and Lipids DegradationFatty Acids Degradation

Some taxa known to possess this pathway include : Escherichia coli K-12 substr. MG1655, Homo sapiens

Expected Taxonomic Range: Bacteria , Entamoebidae, Metazoa

The catabolism of fatty acids proceeds via several routes, which depend on the length of the acids, whether the number of carbons is odd or even, and whether they are saturated or unsaturated. This pathway represents the "core" cycle of β-oxidation, a mechanism that removes two carbon atoms with each turn of the cycle.

Saturated fattty acids that are routed into this core pathway are processed until only two or three carbons remain. When even-numbered fatty acids are broken down, the final product is the two-carbon compound acetyl-CoA, which is a basic intermediate of central metabolism, and can be routed into the TCA cycle for complete catabolism or routed into the glyoxylate cycle to be used for biosynthesis. When odd number fatty acids are broken down, the final product of the pathway is the three-carbon compound propanoyl-CoA, which in Escherichia coli is carboxylated to methylmalonyl-CoA and converted to succinyl-CoA (see propanoyl CoA degradation I).

Unsaturated fatty acids with cis double bonds located at odd-numbered carbon atoms enter the main pathway after a modification (see fatty acid β-oxidation III (unsaturated, odd number)). When cis double bonds are located at even-numbered carbon atoms (such as in linoleate), the acids are modified by a different route (see unsaturated, even numbered fatty acid β-oxidation).

Although enzymes of the pathway handle both short and long chain fatty acids, it is the long chain compounds that induce the enzymes of the pathway [Clark81].

The pathway under anaerobic conditions

In the facultative anaerobic bacterium Escherichia coli the pathway can proceed under anaerobic conditions [Campbell03]. The enzymatic steps are identical, and the main difference is that the product of the pathway, acetyl-CoA, is oxidized using fumarate as the terminal electron acceptor [MorganKiss04]. However, a different set of enzymes is active under anaerobic conditions. In the anaerobic pathway FadI, FadJ, and FadK serve functions parallel to those of FadA, FadB, and FadD in the aerobic pathway [Campbell03]. In contrast to the aerobic pathway, octanoate and decanoate can serve as substrates for the anaerobic fatty acid oxidation pathway [Campbell03].

The glyoxylate cycle is necessary under both anaerobic and aerobic conditions of fatty acid oxidation to provide the carbon and energy for cell growth [Campbell03].

Unification Links: EcoCyc:FAO-PWY

Created 06-Feb-1995 by Riley M, Marine Biological Laboratory
Revised 12-Mar-2012 by Caspi R, SRI International
Reviewed 31-Jul-2013 by Foerster H, Boyce Thompson Institute


Campbell03: Campbell JW, Morgan-Kiss RM, E Cronan J (2003). "A new Escherichia coli metabolic competency: growth on fatty acids by a novel anaerobic beta-oxidation pathway." Mol Microbiol 47(3);793-805. PMID: 12535077

Clark81: Clark D (1981). "Regulation of fatty acid degradation in Escherichia coli: analysis by operon fusion." J Bacteriol 1981;148(2);521-6. PMID: 6271734

MorganKiss04: Morgan-Kiss RM, Cronan JE (2004). "The Escherichia coli fadK (ydiD) gene encodes an anerobically regulated short chain acyl-CoA synthetase." J Biol Chem 279(36);37324-33. PMID: 15213221

Other References Related to Enzymes, Genes, Subpathways, and Substrates of this Pathway

Abe93: Abe H, Ohtake A, Yamamoto S, Satoh Y, Takayanagi M, Amaya Y, Takiguchi M, Sakuraba H, Suzuki Y, Mori M (1993). "Cloning and sequence analysis of a full length cDNA encoding human mitochondrial 3-oxoacyl-CoA thiolase." Biochim Biophys Acta 1216(2);304-6. PMID: 8241273

Andersson96: Andersson B, Wentland MA, Ricafrente JY, Liu W, Gibbs RA (1996). "A "double adaptor" method for improved shotgun library construction." Anal Biochem 236(1);107-13. PMID: 8619474

Antonenkov97: Antonenkov VD, Van Veldhoven PP, Waelkens E, Mannaerts GP (1997). "Substrate specificities of 3-oxoacyl-CoA thiolase A and sterol carrier protein 2/3-oxoacyl-CoA thiolase purified from normal rat liver peroxisomes. Sterol carrier protein 2/3-oxoacyl-CoA thiolase is involved in the metabolism of 2-methyl-branched fatty acids and bile acid intermediates." J Biol Chem 272(41);26023-31. PMID: 9325339

Arnauld: Arnauld S, Fidaleo M, Clemencet MC, Chevillard G, Athias A, Gresti J, Wanders RJ, Latruffe N, Nicolas-Frances V, Mandard S "Modulation of the hepatic fatty acid pool in peroxisomal 3-ketoacyl-CoA thiolase B-null mice exposed to the selective PPARalpha agonist Wy14,643." Biochimie 91(11-12);1376-86. PMID: 19772884

Bairoch93: Bairoch A, Boeckmann B (1993). "The SWISS-PROT protein sequence data bank, recent developments." Nucleic Acids Res. 21:3093-3096. PMID: 8332529

Begrends88: Begrends, Wilke, Engeland, Kurt, Kindl, Helmut (1988). "Characterization of two forms of the multifunctional protein acting in fatty acid beta-oxidation." Arch Biochem Biophys, 263(1): 161-1691.

Behrends88: Behrends W, Engeland K, Kindl H (1988). "Characterization of two forms of the multifunctional protein acting in fatty acid beta-oxidation." Arch Biochem Biophys 263(1);161-9. PMID: 3130799

Beloin04: Beloin C, Valle J, Latour-Lambert P, Faure P, Kzreminski M, Balestrino D, Haagensen JA, Molin S, Prensier G, Arbeille B, Ghigo JM (2004). "Global impact of mature biofilm lifestyle on Escherichia coli K-12 gene expression." Mol Microbiol 51(3);659-74. PMID: 14731270

Binstock81: Binstock JF, Schulz H (1981). "Fatty acid oxidation complex from Escherichia coli." Methods Enzymol 1981;71 Pt C;403-11. PMID: 7024730

Black92: Black PN, DiRusso CC, Metzger AK, Heimert TL (1992). "Cloning, sequencing, and expression of the fadD gene of Escherichia coli encoding acyl coenzyme A synthetase." J Biol Chem 1992;267(35);25513-20. PMID: 1460045

Black97: Black PN, Zhang Q, Weimar JD, DiRusso CC (1997). "Mutational analysis of a fatty acyl-coenzyme A synthetase signature motif identifies seven amino acid residues that modulate fatty acid substrate specificity." J Biol Chem 272(8);4896-903. PMID: 9030548

Bout88: Bout A, Teunissen Y, Hashimoto T, Benne R, Tager JM (1988). "Nucleotide sequence of human peroxisomal 3-oxoacyl-CoA thiolase." Nucleic Acids Res 16(21);10369. PMID: 3194209

Bout91: Bout A, Franse MM, Collins J, Blonden L, Tager JM, Benne R (1991). "Characterization of the gene encoding human peroxisomal 3-oxoacyl-CoA thiolase (ACAA). No large DNA rearrangement in a thiolase-deficient patient." Biochim Biophys Acta 1090(1);43-51. PMID: 1679347

BRENDA14: BRENDA team (2014). Imported from BRENDA version existing on Aug 2014.

Brueton92: Brueton LA, van Herwerden L, Chotai KA, Winter RM (1992). "The mapping of a gene for craniosynostosis: evidence for linkage of the Saethre-Chotzen syndrome to distal chromosome 7p." J Med Genet 29(10);681-5. PMID: 1433226

Campbell02: Campbell JW, Cronan JE (2002). "The enigmatic Escherichia coli fadE gene is yafH." J Bacteriol 184(13);3759-64. PMID: 12057976

Cao01: Cao Y, Dave KB, Doan TP, Prescott SM (2001). "Fatty acid CoA ligase 4 is up-regulated in colon adenocarcinoma." Cancer Res 61(23);8429-34. PMID: 11731423

Cao08: Cao W, Liu N, Tang S, Bao L, Shen L, Yuan H, Zhao X, Lu H (2008). "Acetyl-Coenzyme A acyltransferase 2 attenuates the apoptotic effects of BNIP3 in two human cell lines." Biochim Biophys Acta 1780(6);873-80. PMID: 18371312

Cao98: Cao Y, Traer E, Zimmerman GA, McIntyre TM, Prescott SM (1998). "Cloning, expression, and chromosomal localization of human long-chain fatty acid-CoA ligase 4 (FACL4)." Genomics 49(2);327-30. PMID: 9598324

Chen91a: Chen GL, Balfe A, Erwa W, Hoefler G, Gaertner J, Aikawa J, Chen WW (1991). "Import of human bifunctional enzyme into peroxisomes of human hepatoma cells in vitro." Biochem Biophys Res Commun 178(3);1084-91. PMID: 1651711

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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 Pathway Tools version 19.5 (software by SRI International) on Sun Feb 7, 2016, biocyc14.