The microbial degradation of cyclohexanecarboxylic acid by a β-oxidation pathway with simultaneous induction to the utilization of benzoate

1978 ◽  
Vol 24 (7) ◽  
pp. 847-855 ◽  
Author(s):  
E. R. Blakley
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Characteristic Feature ◽  
Microbial Degradation ◽  
Enzyme Activities ◽  
Caproic Acid ◽  
Acid Cycle ◽  
Cyclohexanecarboxylic Acid ◽  
Cell Extracts ◽  
Induction Process

The metabolism of cyclohexanecarboxylic acid by a bacterium, designated PRL W19, follows a pathway involving β-oxidation of coenzyme A intermediates analogous to the classical oxidation of fatty acids. The organism appears to have the property for the constitutive metabolism of caproic acid, and cell extracts contain high levels of the enzymes required for the functioning of the fatty acid cycle. However, the metabolism of cyclohexanecarboxylic acid requires induction by growth or incubation with an appropriate substrate. Extracts of induced cells contain several enzyme activities which are synthesized in response to the induction process. These enzymes include cyclohexanecarboxyl-CoA synthetase, cyclohexanecarboxyl-CoA dehydrogenase, 1-cyclohexenecarboxyl-CoA hydratase, and trans-2-hydroxycyclohexanecarboxyl-CoA dehydrogenase. A characteristic feature of this organism is that it becomes induced for the metabolism of benzoate and catechol during growth on cyclohexanecarboxylic acid, but benzoate does not appear to be an obligatory intermediate in the metabolism of cyclohexanecarboxylic acid.

scholarly journals GH replacement causing acute hyperglycaemia and ketonuria in a type 1 diabetic patient

2013 ◽  
Vol 2013 ◽  
Author(s):  
Dominic Cavlan ◽  
Shanti Vijayaraghavan ◽  
Susan Gelding ◽  
William Drake
Keyword(s):  
Insulin Resistance ◽  
Fatty Acids ◽  
Type 1 Diabetes ◽  
Fatty Acid ◽  
Diabetic Patient ◽  
Acid Cycle ◽  
Gh Replacement ◽  
Glucose Fatty Acid Cycle ◽  
Gh Excess

Summary A state of insulin resistance is common to the clinical conditions of both chronic growth hormone (GH) deficiency and GH excess (acromegaly). GH has a physiological role in glucose metabolism in the acute settings of fast and exercise and is the only anabolic hormone secreted in the fasting state. We report the case of a patient in whom knowledge of this aspect of GH physiology was vital to her care. A woman with well-controlled type 1 diabetes mellitus who developed hypopituitarism following the birth of her first child required GH replacement therapy. Hours after the first dose, she developed a rapid metabolic deterioration and awoke with hyperglycaemia and ketonuria. She adjusted her insulin dose accordingly, but the pattern was repeated with each subsequent increase in her dose. Acute GH-induced lipolysis results in an abundance of free fatty acids (FFA); these directly inhibit glucose uptake into muscle, and this can lead to hyperglycaemia. This glucose–fatty acid cycle was first described by Randle et al. in 1963; it is a nutrient-mediated fine control that allows oxidative muscle to switch between glucose and fatty acids as fuel, depending on their availability. We describe the mechanism in detail. Learning points There is a complex interplay between GH and insulin resistance: chronically, both GH excess and deficiency lead to insulin resistance, but there is also an acute mechanism that is less well appreciated by clinicians. GH activates hormone-sensitive lipase to release FFA into the circulation; these may inhibit the uptake of glucose leading to hyperglycaemia and ketosis in the type 1 diabetic patient. The Randle cycle, or glucose–fatty acid cycle, outlines the mechanism for this acute relationship. Monitoring the adequacy of GH replacement in patients with type 1 diabetes is difficult, with IGF1 an unreliable marker.

scholarly journals DesT Coordinates the Expression of Anaerobic and Aerobic Pathways for Unsaturated Fatty Acid Biosynthesis in Pseudomonas aeruginosa

2009 ◽  
Vol 192 (1) ◽  
pp. 280-285 ◽  
Author(s):  
Chitra Subramanian ◽  
Charles O. Rock ◽  
Yong-Mei Zhang
Keyword(s):  
Fatty Acids ◽  
Pseudomonas Aeruginosa ◽  
Fatty Acid ◽  
Dna Sequences ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Biosynthesis ◽  
Acid Synthesis ◽  
Cell Extracts ◽  
Translational Start

ABSTRACT The fabA and fabB genes are responsible for anaerobic unsaturated fatty acid formation in Pseudomonas aeruginosa. Expression of the fabAB operon was repressed by exogenous unsaturated fatty acids, and DNA sequences upstream of the translational start site were used to affinity purify DesT. The single protein interaction with the fabAB promoter detected in wild-type cell extracts was absent in the desT deletion strain, as was the repression of fabAB expression by unsaturated fatty acids. Thus, DesT senses the overall composition of the acyl-coenzyme A pool to coordinate the expression of the operons for the anaerobic (fabAB) and aerobic (desCB) pathways for unsaturated fatty acid synthesis.

scholarly journals Different oral sensitivities to and sensations of short-, medium-, and long-chain fatty acids in humans

2014 ◽  
Vol 307 (3) ◽  
pp. G381-G389 ◽  
Author(s):  
Cordelia A. Running ◽  
Richard D. Mattes
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Textural Properties ◽  
Caproic Acid ◽  
Mineral Oil ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Nonesterified Fatty Acids ◽  
Oral Sensitivity

Fatty acids that vary in chain length and degree of unsaturation have different effects on metabolism and human health. As evidence for a “taste” of nonesterified fatty acids (NEFA) accumulates, it may be hypothesized that fatty acid structures will also influence oral sensations. The present study examined oral sensitivity to caproic (C6), lauric (C12), and oleic (C18:1) acids over repeated visits. Analyses were also conducted on textural properties of NEFA emulsions and blank solutions. Oral thresholds for caproic acid were lower compared with oleic acid. Lauric acid thresholds were intermediate but not significantly different from either, likely due to lingering irritating sensations that prevented accurate discrimination. From particle size analysis, larger droplets were observed in blank solutions when mineral oil was used, leading to instability of the emulsion, which was not observed when emulsions contained NEFA or when mineral oil was removed from the blank. Rheological data showed no differences in viscosity among samples except for a slightly higher viscosity with oleic acid concentrations above 58 mM. Thus, texture was unlikely to be the property used to distinguish between the samples. Differences in oral detection and sensation of caproic, lauric, and oleic acids may be due to different properties of the fatty acid alkyl chains.

scholarly journals Analisis Asam Lemak Daging Anjing pada Bakso Sapi Menggunakan Gas Chromatography Mass Spectrometry (GCMS) yang Dikombinasikan dengan PCA (Principal Component Analysis)

2018 ◽  
Vol 1 (2) ◽  
pp. 117
Author(s):  
Irfan Nugraha ◽  
Pri Iswati Utami ◽  
Wiranti Sri Rahayu
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Principal Component Analysis ◽  
Fatty Acid ◽  
Qualitative Analysis ◽  
Principal Component ◽  
Caproic Acid ◽  
Eicosatrienoic Acid ◽  
Rapid Screening ◽  
Gas Chromatography Mass Spectrometry

ABSTRAKTingginya perbedaan harga daging, membuat beberapa penjual yang tidak etis mengganti daging sapi dengan daging anjing secara sengaja untuk mendapatkan keuntungan ekonomis. Tujuan dilakukan penelitian ini adalah untuk mengetahui kemampuan GCMS yang dikombinasi dengan kemometrika PCA untuk analisis cepat dari asam lemak anjing pada bakso formulasi dan bakso sapi di pasaran. Metode penelitian ini adalah non eksperimental berupa identifikasi profil asam lemak daging anjing  pada bakso sapi formulasi dan bakso sapi di pasaran. Hasil penelitian yang didapat berupa profil kromatogram GCMS menunjukkan bahwa terdapat perbedaan komposisi asam lemak antara daging anjing dan sapi. Pada lemak daging anjing muncul beberapa asam lemak yang tidak dimiliki oleh lemak daging sapi diantaranya asam kaproat, asam siklopentanetridekanoat, asam arakhidonat, asam 7,10,13- eikosatrienoat, asam 9,12,15- oktadekatrienoat. Analisis kualitatif dari kromatogram GCMS menggunakan PCA menunjukkan lemak sapi, anjing, kambing, babi dan ayam dapat diidentifikasi dan dibedakan. Analisis kualitatif kandungan lemak anjing dalam bakso sapi formulasi menunjukkan perbedaan antara bakso formulasi yang memiliki kedekatan mirip dengan lemak sapi serta yang mirip dengan lemak anjing. Analisis kualitatif lemak anjing pada bakso sapi di pasaran menunjukkan sampel tidak mengandung lemak anjing.Kata kunci : bakso, GCMS, lemak daging anjingABSTRACTDue to the high difference of meat price, some unethical seller replaces beef intentionally with dog meat to get economical profits. The objective of this study is to assess the capability of GCMS coupled with chemometrics of PCA for rapid screening of dog fat in beef meatball formulation and beef meatballs in the market. The method of this research is non experimental that is identification of fatty acid profile of dog meat in beef meatball simulation and beef meatballs in the market. The result obtained from GCMS chromatogram profile showed that there is a difference in fatty acid composition between beef and dog meat. In dog meat fat appears some fatty acids that are not owned by beef fat i.e caproic acid, cyclopentanetridecanoic acid, arachidonate acid, 7,10,13-eicosatrienoic acid, 9,12,15-octadecatrienoic acid. Qualitative analysis from GCMS chromatogram using PCA showed that beef, dog, goat, pork and chicken can be identified and differentiated. Qualitative analysis of dog fat in simulated beef meatballs showed difference between simulated meatballs that have similar proximity to beef's fat as well as those that are similar to dog fat. Qualitative analysis of dog fat in beef meatballs in the market showed the sample doesn't contain dog fat. Keywords : dog meat fat, GCMS, meatball

scholarly journals Effects of pent-4-enoate on cellular redox state, glycolysis and fatty acid oxidation in isolated perfused rat heart

1978 ◽  
Vol 170 (2) ◽  
pp. 235-240 ◽  
Author(s):  
J. Kalervo Hiltunen ◽  
V. Pekka Jauhonen ◽  
Markku J. Savolainen ◽  
Ilmo E. Hassinen
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Citric Acid ◽  
Redox State ◽  
Citric Acid Cycle ◽  
Beating Heart ◽  
Acid Oxidation ◽  
O2 Consumption ◽  
Cellular Redox ◽  
Acid Cycle

The metabolic effects of pent-4-enoate were studied in beating and potassium-arrested perfused rat hearts. The addition of 0.8mm-pent-4-enoate to the fluid used to perfuse a potassium-arrested heart resulted in a 70% increase in the O2 consumption and a 66% decrease in the glycolytic flux as measured in terms of the de-tritiation of [3-3H]glucose, although the proportion of the O2 consumption attributable to glucose oxidation decreased from an initial 30% to 10%. The pent-4-enoate-induced increase in O2 consumption was only 15% in the beating heart. In the potassium-arrested heart, pent-4-enoate stimulated palmitate oxidation by more than 100% when measured in terms of the production of 14CO2 from [1-14C]palmitate, but in the beating heart palmitate oxidation was inhibited. Perfusion of the heart with pent-4-enoate had no effect on the proportion of pyruvate dehydrogenase found in the active form, in spite of large changes in the CoASH and acetyl-CoA concentrations and changes in their concentration ratios. The effects of pent-4-enoate on the cellular redox state were dependent on the ATP consumption of the heart. In the beating heart, pent-4-enoate caused a rapid mitochondrial NAD+ reduction that subsequently faded out, so that the final state was more oxidized than the initial state. The arrested heart, however, remained in a more reduced state than initially, even after the partial re-oxidation that followed the initial rapid NAD+ reduction. The ability of pent-4-enoate to increase or decrease fatty acid oxidation can be explained on the basis of the differential effects of pent-4-enoate on the concentration of citric acid-cycle intermediates under conditions of high or low ATP consumption of the myocardial cell. The proportion of the fatty acids in the fuel consumed by the heart is probably primarily determined by the regulatory mechanisms of glycolysis. When pent-4-enoate causes an increase in the citric acid-cycle intermediates, feedback inhibition of glycolysis results in an increase in the oxidation of fatty acids.

High-altitude acclimation increases the triacylglycerol/fatty acid cycle at rest and during exercise

2001 ◽  
Vol 281 (3) ◽  
pp. E537-E544 ◽  
Author(s):  
Grant B. McClelland ◽  
Peter W. Hochachka ◽  
Shannon P. Reidy ◽  
Jean-Michel Weber
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Lipid Oxidation ◽  
High Altitude ◽  
Sea Level ◽  
Total Lipid ◽  
Level Control ◽  
Nonesterified Fatty Acids ◽  
Acid Cycle

High-altitude acclimation alters lipid metabolism during exercise, but it is unknown whether this involves changes in rates of lipolysis or reesterification, which form the triacylglycerol/fatty acid (TAG/FA) cycle. We combined indirect calorimetry with [2-3H]glycerol and [1-14C]palmitate infusions to simultaneously measure total lipid oxidation, lipolysis, and rate of appearance (Ra) of nonesterified fatty acids (NEFA) in high-altitude-acclimated (HA) rats exercising at 60% maximal O2 uptake (V˙o 2 max). During exercise, relative total lipid oxidation (%V˙o 2) equaled sea-level control (SL) values; however, acclimation greatly stimulated lipolysis (+75%) but had no effect on Ra NEFA. As a result, TAG/FA cycling increased (+119%), due solely to an increase in recycling (+144%) within adipocytes. There was no change in either group in these variables with the transition from rest to exercise. We conclude that, in HA, 1) acclimation is a potent stimulator of lipolysis; 2) rats do not modify TAG/FA cycling with the transition to exercise; and 3) in normoxia, HA and SL derive the same fraction of their total energy from lipids and carbohydrates.

The microbial degradation of cyclohexanecarboxylic acid: a pathway involving aromatization to form p-hydroxybenzoic acid

1974 ◽  
Vol 20 (10) ◽  
pp. 1297-1306 ◽  
Author(s):  
E. R. Blakley
Keyword(s):  
Methylene Blue ◽  
Electron Acceptor ◽  
Microbial Degradation ◽  
Protocatechuic Acid ◽  
Hydroxybenzoic Acid ◽  
Cyclohexanecarboxylic Acid ◽  
Cell Extracts

A strain of Arthrobacter catabolizes cyclohexanecarboxylic acid by a pathway involving aromatization of the ring before its cleavage. The pathway includes the following intermediates: trans-4-hydroxycyclohexanecarboxylic acid, 4-ketocyclohexanecarboxylic acid, p-hydroxybenzoic acid, protocatechuic acid, and β-ketoadipic acid. The oxidation of 4-hydroxycyclohexanecarboxylic acid by cell extracts specifically requires NAD+ and results in the production of 4-ketocyclohexanecarboxylic acid. The latter compound is oxidized in the presence of a suitable electron acceptor, such as oxygen, methylene blue, or 2,6-dichlorophenolindophenol, to p-hydroxybenzoic acid.

scholarly journals Lactococcus lactis fabH, Encoding β-Ketoacyl-Acyl Carrier Protein Synthase, Can Be Functionally Replaced by the Plasmodium falciparum Congener

2010 ◽  
Vol 76 (12) ◽  
pp. 3959-3966 ◽  
Author(s):  
Yu Du ◽  
Jolyn E. Gisselberg ◽  
Jacob D. Johnson ◽  
Patricia J. Lee ◽  
Sean T. Prigge ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Plasmodium Falciparum ◽  
Fatty Acid ◽  
Lactococcus Lactis ◽  
Fatty Acid Synthase ◽  
Acyl Carrier Protein ◽  
Transcriptional Analysis ◽  
Carrier Protein ◽  
Cell Extracts ◽  
Fas Ii

ABSTRACT Plasmodium falciparum, in addition to scavenging essential fatty acids from its intra- and intercellular environments, possesses a functional complement of type II fatty acid synthase (FAS) enzymes targeted to the apicoplast organelle. Recent evidence suggests that products of the plasmodial FAS II system may be critical for the parasite's liver-to-blood cycle transition, and it has been speculated that endogenously generated fatty acids may be precursors for essential cofactors, such as lipoate, in the apicoplast. β-Ketoacyl-acyl carrier protein (ACP) synthase III (pfKASIII or FabH) is one of the key enzymes in the initiating steps of the FAS II pathway, possessing two functions in P. falciparum: the decarboxylative thio-Claisen condensation of malonyl-ACP and various acyl coenzymes A (acyl-CoAs; KAS activity) and the acetyl-CoA:ACP transacylase reaction (ACAT). Here, we report the generation and characterization of a hybrid Lactococcus lactis strain that translates pfKASIII instead of L. lactis f abH to initiate fatty acid biosynthesis. The L. lactis expression vector pMG36e was modified for the efficient overexpression of the plasmodial gene in L. lactis. Transcriptional analysis indicated high-efficiency overexpression, and biochemical KAS and ACAT assays confirm these activities in cell extracts. Phenotypically, the L. lactis strain expressing pfKASIII has a growth rate and fatty acid profiles that are comparable to those of the strain complemented with its endogenous gene, suggesting that pfKASIII can use L. lactis ACP as substrate and perform near-normal function in L. lactis cells. This strain may have potential application as a bacterial model for pfKASIII inhibitor prescreening.

scholarly journals Palmitate inhibits liver glycolysis. Involvement of fructose 2,6-bisphosphate in the glucose/fatty acid cycle

1988 ◽  
Vol 251 (2) ◽  
pp. 541-545 ◽  
Author(s):  
L Hue ◽  
L Maisin ◽  
M H Rider
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Ketone Bodies ◽  
Acid Cycle ◽  
Glucose Fatty Acid Cycle ◽  
Inhibition Of Glycolysis ◽  
Beta Hydroxybutyrate ◽  
Fasted Rats

In hepatocytes from overnight-fasted rats incubated with glucose, palmitate decreased the production of lactate, the detritiation of [2-3H]- and [3-3H]-glucose, and the concentration of fructose 2,6-bisphosphate. Similarly, perfusion of hearts from fed rats with beta-hydroxybutyrate resulted in an inhibition of the detritiation of [3-3H]glucose and a fall in fructose 2,6-bisphosphate concentration. This fall could result from an increase in citrate (hepatocytes and heart) and sn-glycerol 3-bisphosphate concentration. It is suggested that a fall in fructose 2,6-bisphosphate concentration participates in the inhibition of glycolysis by fatty acids and ketone bodies.

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