scholarly journals Metabolic engineering strategies to produce medium-chain oleochemicals via acyl-ACP:CoA transacylase activity

2021 ◽  
Author(s):  
Qiang Yan ◽  
William Cordell ◽  
Michael Jindra ◽  
Dylan Courtney ◽  
Madeline Kuckuk ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Metabolic Engineering ◽  
Acyl Chain ◽  
Fatty Alcohols ◽  
Methyl Ketones ◽  
Beta Oxidation ◽  
Medium Chain ◽  
Genetic Modifications ◽  
Engineering Strategy ◽  
Transacylase Activity

Abstract Microbial lipid metabolism is an attractive route for producing aliphatic chemicals, commonly referred to as oleochemicals. The predominant metabolic engineering strategy centers on heterologous thioesterases capable of producing fatty acids of desired size. To convert acids to desired oleochemicals (e.g. fatty alcohols, ketones), metabolic engineers modify cells to block beta-oxidation, reactivate fatty acids as coenzyme-A thioesters, and redirect flux towards termination enzymes with broad substrate utilization ability. These genetic modifications narrow the substrate pool available for the termination enzyme but cost one ATP per reactivation - an expense that could be saved if the acyl-chain was directly transferred from ACP- to CoA-thioester. In this work, we demonstrate an alternative acyl-transferase strategy for producing medium-chain oleochemicals. Through bioprospecting, mutagenesis, and metabolic engineering, we developed strains of Escherichia coli capable of producing over 1 g/L of medium-chain free fatty acids, fatty alcohols, and methyl ketones using the transacylase strategy.

A metabolic engineering strategy for producing free fatty acids by theYarrowia lipolyticayeast based on impairment of glycerol metabolism

2017 ◽  
Vol 115 (2) ◽  
pp. 433-443 ◽  
Author(s):  
Evgeniya Y. Yuzbasheva ◽  
Elizaveta B. Mostova ◽  
Natalia I. Andreeva ◽  
Tigran V. Yuzbashev ◽  
Alexander S. Fedorov ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Metabolic Engineering ◽  
Free Fatty Acids ◽  
Glycerol Metabolism ◽  
Metabolic Engineering Strategy ◽  
Engineering Strategy

Biogenesis of dicarboxylic acids in rat liver homogenate studied by 13C labeling

1991 ◽  
Vol 261 (6) ◽  
pp. E719-E724
Author(s):  
S. J. Jin ◽  
K. Y. Tserng
Keyword(s):  
Fatty Acids ◽  
Rat Liver ◽  
Liver Homogenate ◽  
Dicarboxylic Acids ◽  
Long Chain Fatty Acids ◽  
Beta Oxidation ◽  
Selected Ion Monitoring ◽  
Medium Chain ◽  
Long Chain ◽  
Chain Fatty Acids

The aim of this investigation is to assess whether long-chain fatty acids can be a substrate for omega-oxidation and the subsequent beta-oxidation to produce medium-chain dicarboxylic acids normally found in urine. Isolated rat liver 10,000 g supernatant and pellet fractions were used as the source of enzymes. The metabolism of palmitate was studied using [1,2,3,4-13C4]hexadecanoic acid as tracer. Selected ion monitoring mass spectrometry was utilized for the determination of isotope enrichments in precursor and products. Palmitate was found to be a good substrate for omega-oxidation; the rate was only slightly slower than decanoate. The beta-oxidation of [1,2,3,4-13C4]hexadecanedioic acid yielded labeled adipic, suberic, and sebacic acids. Isotope distribution in these dicarboxylic acids consisted mostly of unlabeled molecules (M + 0) and molecules labeled with four 13C (M + 4), in agreement with a beta-oxidation initiated equally from both carboxyl ends of the precursor. Significant enrichments (1-8%) with only two 13C labels (M + 2) indicate a partial bidirectional beta-oxidation. The direct metabolic conversion of hexadecanedioate to succinate was documented by the significant enrichment (1.40-1.90%) in M + 4 of succinate. These data indicate that long-chain fatty acids can be a substrate for the production of medium-chain dicarboxylates and the eventual direct conversion to succinate.

Mitochondrial and peroxisomal fatty acid oxidation in elasmobranchs

1990 ◽  
Vol 258 (3) ◽  
pp. R756-R762 ◽  
Author(s):  
C. D. Moyes ◽  
L. T. Buck ◽  
P. W. Hochachka
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Salmo Gairdneri ◽  
Acid Oxidation ◽  
Beta Oxidation ◽  
Medium Chain ◽  
Medium Chain Fatty Acids ◽  
Palmitoyl Carnitine ◽  
Red Muscle ◽  
Chain Fatty Acids

In heart and red muscle of dogfish (Squalus acanthias), the maximal activities of the fatty acid catabolizing enzyme carnitine palmitoyltransferase (CPT) are less than 5% the rate in the same tissues of teleosts (carp, Cyprinus carpio; trout, Salmo gairdneri). CPT activities in these tissues of hagfish (Eptatretus stouti) are approximately 10% the rate in teleosts. However, the maximal activities of the beta-oxidation enzyme beta-hydroxyacyl-CoA dehydrogenase (HOAD) in dogfish red muscle and heart are similar to these tissues in the other species. This paradox prompted a more detailed study on the capacity of mitochondria from dogfish cardiac and red skeletal muscles to utilize fatty acids, possibly by a CPT-independent pathway. Free fatty acids were not oxidized by mitochondria from red muscle (hexanoate, octanoate, decanoate, and palmitate) or from heart (octanoate, palmitate). Neither hyposmotic incubation nor addition of 5 mM ATP could stimulate oxidation of octanoate or palmitate in either preparation, suggesting that these tissues have little capacity to oxidize fatty acids by a carnitine-independent pathway. Palmitoyl carnitine oxidation was detectable at very low rates in these mitochondria only with hyposmotic incubation. Octanoyl carnitine was oxidized at greater rates than palmitoyl carnitine, 10% the rate of pyruvate in both tissues, suggesting that medium-chain fatty acids could be physiologically relevant fuels in elasmobranchs if available to heart and red muscle. One potential source of medium-chain fatty acids is hepatic peroxisomal beta-oxidation, which occurs in dogfish liver at maximal activities similar to carp and trout liver. However, based on relative rates of oxidation, it is likely that dogfish heart and red muscle metabolism are fueled primarily by carbohydrate and ketone bodies.

Carnitine effects on coenzyme A profiles in rat liver with hypoglycin inhibition of multiple dehydrogenases

1997 ◽  
Vol 272 (3) ◽  
pp. E359-E366 ◽  
Author(s):  
Y. K. Lieu ◽  
B. Y. Hsu ◽  
W. A. Price ◽  
B. E. Corkey ◽  
C. A. Stanley
Keyword(s):  
Fatty Acids ◽  
Coenzyme A ◽  
Genetic Disorders ◽  
Genetic Defect ◽  
Rat Hepatocytes ◽  
Carnitine Supplementation ◽  
Beta Oxidation ◽  
Medium Chain ◽  
Chain Acyl ◽  
Chain Fatty Acids

To examine the changes in coenzyme A profile and the possible corrective effects of carnitine supplementation in the genetic disorders of mitochondrial beta-oxidation, we carried out experiments using an inhibitor of multiple acyl-CoA dehydrogenase enzymes, methylenecyclopropaneacetic acid (MCPA), in rat hepatocytes. MCPA irreversibly inhibited ketone synthesis from straight-chain fatty acids (butyrate, octanoate, palmitate) and branched-chain fatty acids (alpha-ketoisocaproate) with a parallel 70-90% reduction of hepatocyte acetyl-CoA levels. Alone, MCPA or substrates halved free CoA levels to 15% of total CoA and doubled short- and medium-chain acyl-CoA levels to 30% of total CoA. With MCPA plus substrates combined, free CoA levels were 10% of total CoA, and short- and medium-chain acyl-CoA levels were 45% of total CoA. Comparable changes in CoA profiles were found in a patient with a severe genetic defect in beta-oxidation. Neither the suppression of ketogenesis nor the alterations in CoA profiles induced by MCPA inhibition could be corrected by carnitine supplementation.

scholarly journals Increasing medium chain fatty acids production in Yarrowia lipolytica by metabolic engineering

2018 ◽  
Vol 17 (1) ◽  
Author(s):  
Coraline Rigouin ◽  
Christian Croux ◽  
Vinciane Borsenberger ◽  
Maher Ben Khaled ◽  
Thierry Chardot ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Metabolic Engineering ◽  
Yarrowia Lipolytica ◽  
Medium Chain ◽  
Medium Chain Fatty Acids ◽  
Chain Fatty Acids

Enhanced Bioavailability of Curcumin Nanoemulsions Stabilized with Phosphatidylcholine Modified with Medium Chain Fatty Acids

2017 ◽  
Vol 14 (3) ◽  
pp. 377-385 ◽  
Author(s):  
Angelica A. Ochoa-Flores ◽  
Josafat A. Hernández-Becerra ◽  
Adriana Cavazos-Garduño ◽  
Ida Soto-Rodríguez ◽  
Maria Guadalupe Sanchez-Otero ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Medium Chain ◽  
Medium Chain Fatty Acids ◽  
Chain Fatty Acids

scholarly journals Differential Effects of Fatty Acid Saturation and Chain Length on NASH in Juvenile Iberian Pigs

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 682-682 ◽  
Author(s):  
Kayla Dillard ◽  
Morgan Coffin ◽  
Gabriella Hernandez ◽  
Victoria Smith ◽  
Catherine Johnson ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Body Weight ◽  
Fatty Acid ◽  
Liver Injury ◽  
Olive Oil ◽  
Coconut Oil ◽  
Long Chain Fatty Acids ◽  
Medium Chain ◽  
Long Chain ◽  
Chain Fatty Acids

Abstract Objectives Non-alcoholic fatty liver disease (NAFLD) represents the major cause of pediatric chronic liver pathology in the United States. The objective of this study was to compare the relative effect of inclusion of isocaloric amounts of saturated medium-chain fatty acids (hydrogenated coconut oil), saturated long-chain fatty acids (lard) and unsaturated long-chain fatty acids (olive oil) on endpoints of NAFLD and insulin resistance. Methods Thirty-eight 15-d-old Iberian pigs were fed 1 of 4 diets containing (g/kg body weight × d) 1) control (CON; n = 8): 0 g fructose, 10.5 g fat, and 187 kcal metabolizable energy (ME), 2) lard (LAR; n = 10): 21.6 g fructose, 17.1 g fat (100% lard) and 299 kcal ME, 3) hydrogenated coconut oil (COCO; n = 10): 21.6 g fructose, 16.9 g fat (42.5% lard and 57.5% coconut oil) and 299 kcal ME, and 4) olive oil (OLV, n = 10): 21.6 g fructose, 17.1 g fat (43.5% lard and 56.5% olive oil) and 299 kcal ME, for 9 consecutive weeks. Body weight was recorded every 3 d. Serum markers of liver injury and dyslipidemia were measured on d 60 at 2 h post feeding, with all other serum measures assessed on d 70. Liver tissue was collected on d 70 for histology, triacylglyceride (TG) quantification, and metabolomics analysis. Results Tissue histology indicated the presence of steatosis in LAR, COCO and OLV compared with CON (P ≤ 0.001), with a further increase in in non-alcoholic steatohepatitis (NASH) in OLV and COCO compared with LAR (P ≤ 0.01). Alanine and aspartate aminotransferases were higher in COCO and OLV (P ≤ 0.01) than CON. All treatment groups had lower liver concentrations of methyl donor's choline and betaine versus CON, while bile acids were differentially changed (P ≤ 0.05). COCO had higher levels of TGs with less carbons (Total carbons < 52) than all other groups (P ≤ 0.05). Several long-chain acylcarnitines involved in fat oxidation were higher in OLV versus all other groups (P ≤ 0.05). Conclusions Inclusion of fats enriched in medium-chain saturated and long-chain unsaturated fatty acids in a high-fructose high-fat diet increased liver injury, compared with fats with a long-chain saturated fatty acid profile. Further research is required to investigate the mechanisms causing this difference in physiological response to these dietary fat sources. Funding Sources ARI, AcornSeekers.

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