scholarly journals Biosynthesis of cyclopropyl long-chain fatty acids from cyclopropanecarboxylic acid by mammalian tissues in vitro

1968 ◽  
Vol 109 (3) ◽  
pp. 449-455 ◽  
Author(s):  
W. G. Duncombe ◽  
T. J. Rising
Keyword(s):  
Fatty Acids ◽  
Rat Liver ◽  
Liver Homogenate ◽  
Supernatant Fraction ◽  
Long Chain Fatty Acids ◽  
Straight Chain ◽  
Cyclopropanecarboxylic Acid ◽  
Mammalian Tissues ◽  
Chain Fatty Acids

1. Radioactivity from cyclopropane[14C]carboxylic acid is incorporated into fatty acids in vitro by rat and guinea-pig adipose tissue, by rat liver slices and by the supernatant fraction of rat liver homogenate. 2. The labelled acids are different from endogenous straight-chain fatty acids, and evidence is produced that they consist of a cyclopropyl ring in the ω-position, the remainder of the chain being built up from C2 units (not derived from cyclopropanecarboxylic acid) in the normal way via the malonate pathway. 3. It is suggested that these unnatural acids have some metabolic effect related to the hypoglycaemic action of cyclopropanecarboxylic acid.

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.

scholarly journals Rumen Fermentation In Vitro as Influenced by Long Chain Fatty Acids

1984 ◽  
Vol 67 (7) ◽  
pp. 1439-1444 ◽  
Author(s):  
William Chalupa ◽  
Bonnie Rickabaugh ◽  
D. Kronfeld ◽  
S. David Sklan
Keyword(s):  
Fatty Acids ◽  
Rumen Fermentation ◽  
Long Chain Fatty Acids ◽  
Long Chain ◽  
Chain Fatty Acids

scholarly journals The Multifunctional β-Oxidation Enzyme Is Required for Full Symptom Development by the Biotrophic Maize Pathogen Ustilago maydis

2006 ◽  
Vol 5 (12) ◽  
pp. 2047-2061 ◽  
Author(s):  
Jana Klose ◽  
James W. Kronstad
Keyword(s):  
Fatty Acids ◽  
Ustilago Maydis ◽  
Long Chain Fatty Acids ◽  
In Planta ◽  
Gene Encoding ◽  
Metabolic Role ◽  
Fungal Phytopathogen ◽  
Long Chain ◽  
Chain Fatty Acids

ABSTRACT The transition from yeast-like to filamentous growth in the biotrophic fungal phytopathogen Ustilago maydis is a crucial event for pathogenesis. Previously, we showed that fatty acids induce filamentation in U. maydis and that the resulting hyphal cells resemble the infectious filaments observed in planta. To explore the potential metabolic role of lipids in the morphological transition and in pathogenic development in host tissue, we deleted the mfe2 gene encoding the multifunctional enzyme that catalyzes the second and third reactions in β-oxidation of fatty acids in peroxisomes. The growth of the strains defective in mfe2 was attenuated on long-chain fatty acids and abolished on very-long-chain fatty acids. The mfe2 gene was not generally required for the production of filaments during mating in vitro, but loss of the gene blocked extensive proliferation of fungal filaments in planta. Consistent with this observation, mfe2 mutants exhibited significantly reduced virulence in that only 27% of infected seedlings produced tumors compared to 88% tumor production upon infection by wild-type strains. Similarly, a defect in virulence was observed in developing ears upon infection of mature maize plants. Specifically, the absence of the mfe2 gene delayed the development of teliospores within mature tumor tissue. Overall, these results indicate that the ability to utilize host lipids contributes to the pathogenic development of U. maydis.

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