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1.
A 10-fold purification of sucrose sucrose fructosyl transferase from Cichorium intybus roots was achieved by ammonium sulphate fractionation and DEAE-cellulose column chromatography. The energy of activation for this enzyme was ca 48 kJ/mol sucrose. Sucrose sucrose fructosyl transferase and invertase were prominent during early months of growth. Evidence obtained from: (1) the changes in carbohydrate composition at monthly intervals; (2) comparative studies on fructosyl transferase and invertase at different stages of root growth; and (3) incubation studies with [14C]glucose, [14C]fructose and [14C]sucrose revealed that, during the later stages of root growth, fructosan hydrolase is responsible for fructosan hydrolysis. No evidence for the direct transfer of fructose from sucrose to high Mr glucofructosans was obtained. 相似文献
2.
Christopher J. Pollock 《Phytochemistry》1979,18(5):777-779
Chemical analysis of leaf base tissue of Dactylis glomerate failed to detect any low MW oligosaccharide intermediates during fructosan synthesis. Extracts of tissue harvested at various times after the incorporation of 14CO2 showed a decline in radioactivity in sucrose and an equivalent rise in high MW fructosan with no significant accumulation of radioactivity in oligosaccharides. No evidence was obtained for the existence of nucleotide fructose in the tissue, indicating that fructosan synthesis occurs by direct transfer of fructosyl residues from sucrose to the polymer. 相似文献
3.
《Neurochemistry international》1986,8(1):77-82
This study focuses on the activity of the pentose-phosphate pathway and its relationship to de novo synthesis of fatty acids and cholesterol in oligodendrocyte-enriched glial cell cultures derived from 1-week old rat brain. The proportion of glucose that was metabolized along the pentose-phosphate pathway was estimated by measuring 14CO2 production from [1-14C]-, [2-14C]- and [6-14C]glucose, the utilization of glucose and the production of lactate. Incorporation of 14C from [14C]glucose and from [3-14C]acetoacetate into lipids was analysed. The pentose- phosphate pathway produced much more CO2 from glucose than the Krebs cycle, although it accounted for only a small part of the consumption of glucose (< 3%). The higher 14CO2 production from [2-14C]glucose than from [6-14C]glucose indicated that recycling of the products of the pentose-phosphate pathway takes place in these cells.Gradual inhibition of the pathway with increasing concentrations of 6-aminonicotinamide resulted in a parallel inhibition of the conversion of acetoacetate and of glucose into fatty acids and into cholesterol. Glycolysis was also strongly inhibited in the presence of 6-aminonicotinamide whereas the activity of the Krebs cycle was not affected.These results suggest that de novo synthesis of fatty acids and cholesterol by oligodendrocytes of neonatal rats is closely geared to the activity of the pentose-phosphate pathway in these cells. 相似文献
4.
About ScienceDirect 《BBA》1978,504(3):466-467
Culture of Trypanosoma cruzi (Tulahuen strain) in the presence of ethidium bromide (1–20 μg/ml) resulted in dyskinetoplasty and inhibition of growth, to an extent depending on the dye concentration and the medium composition. The ethidium bromide-induced dyskinetoplasty caused a decrease of (a) the cytochrome content of epimastigotes (a,a3 and b species); (b) the rate of respiration (endogenous or supported by D-glucose); and (c) the rate of production of 14CO2 from [2-14C]acetate and [1-14C]glucose. [2-14C]Acetate oxidation to 14CO2 was affected by dyskinetoplasty more than [1-14C]glucose oxidation, particularly at the exponential growth phase. With dyskinetoplastic epimastigotes, diminution of 14CO2 production from [2-14C]acetate largely exceeded that of oxygen uptake, while with [1-14C]glucose, 14CO2production and respiration were affected to about the same extent. Dyskinetoplasty also decreased the incorporation of [2-14C]acetate carbon into intermediates of the tricarboxylic acid cycle and related amino acids, and modified the distribution pattern of 14C in accordance with the decrease of respiration. Reduction of cytochrome content of epimastigotes by restriction of heme compounds during growth decreased 14CO2 production from [2-14C]acetate, like the ethidium-induced dyskinetoplasty. The same occurred after inhibition of electron transfer by antimycin and cyanide, though to a much more significant extent, thus confirming the functional association of electron transport at the mitochondrial cytochrome system of T. cruzi and the enzymatic reactions of the tricarboxylic acid cycle. 相似文献
5.
A quantitative triterpene analysis was made of latex stem tissue of Euphorbia lathyris. Young plants seedlings of E. lathyris were incubated with various labelled precursors. Incorporation into triterpenes was obtained from [2-14C]mevalonic acid, [1-14C]acetate, [3-14C]pyruvate, [U-14C]sucrose, [U-14C]glucose, [U-14C]xylose, [U-14C]glyoxylate, [2,3-14C]succinic acid, [1-14C]glycerol [U-14C]serine. Both sugars tyrosine appeared to be effective precursors in DOPA synthesis inside the laticifers. Exogenously supplied mevalonic acid was only involved in triterpene synthesis outside the laticifers. GC-RC of triterpenes synthesized from [U-14C]glucose revealed the origin of these compounds in the latex. The labelled triterpenes obtained after incorporation of the other mentioned labelled precursors were only partly synthesized in the laticifers. For quantitative data on latex triterpene synthesis seedlings were incubated with [U-14C]sucrose, [U-14C]glucose, [U-14C]xylose [1-14C]acetate in the presence of increasing amounts of unlabelled substrate. From the amount of 14C incorporated into the triterpenes the amount of substrate directly involved in triterpene synthesis was calculated, as was the absolute triterpene yield. Sucrose showed the highest triterpene yield, equivalent to the daily increase of the triterpene content of growing seedlings. The possible significance of the other precursors in triterpene synthesis in the laticifers is discussed. 相似文献
6.
Abstract— Replacement of bicarbonate-Locke incubation medium with feline CSF reduced [14C]ACh formation from [U-14C]glucose by rat brain mince approx 30%. CSF was obtained from a cannula leading to the cisterna magna of freely moving cats. The component of CSF responsible for inhibition was characterized as a dialyzable heat-stable organic anion. Choline acetyltransferase activity was not altered by CSF. [14C]ACh synthesis and 14CO2 production from [U-14C]glucose but not from [2-14C]-pyruvate were inhibited by CSF, suggesting inhibition in the metabolism of glucose to pyruvate. The anionic fraction of human CSF was as potent as that from feline CSF in inhibiting 14CO2 production from [U-14C]glucose. Brain hexokinase was inhibited by the anionic fraction of feline CSF. The inhibition was non-competitive with respect to glucose and uncompetitive with respect to ATP. It is suggested that inhibition of hexokinase by CSF was responsible at least in part for the inhibition of glucose metabolism which resulted in decreased [14C]ACh synthesis and 14CO2 production. 相似文献
7.
The pathway of phloem unloading and the metabolism of translocated sucrose were determined in corn (Zea mays) seedling roots. Several lines of evidence show that exogenous sucrose, unlike translocated sucrose, is hydrolyzed in the apoplast prior to uptake into the root cortical cells. These include (a) presence of cell wall invertase activity which represents 20% of the total tissue activity; (b) similarity in uptake and metabolism of [14C]sucrose and [14C]hexoses; and (c) randomization of 14C within the hexose moieties of intracellular sucrose following accumulation of [14C] (fructosyl)sucrose. Conversely, translocated sucrose does not undergo apoplastic hydrolysis during unloading. Asymmetrically labeled sucrose ([14C](fructose)sucrose), translocated from the germinating kernels to the root, remained intact indicating a symplastic pathway for unloading. In addition, isolated root protoplasts and vacuoles were used to demonstrate that soluble invertase activity (Vmax = 29 micromoles per milligram protein per hour, Km = 4 millimolar) was located mainly in the vacuole, suggesting that translocated sucrose entered via the symplasm and was hydrolyzed at the vacuole prior to metabolism. 相似文献
8.
Substrates for Sulfate Reduction and Methane Production in Intertidal Sediments 总被引:16,自引:12,他引:4
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The activity of and potential substrates for methane-producing bacteria and sulfate-reducing bacteria were examined in marsh, estuary, and beach intertidal sediments. Slow rates of methane production were detected in all sediments, although rates of sulfate reduction were 100- to 1,000-fold higher. After sulfate was depleted in sediments, the rates of methane production sharply increased. The addition of methylamine stimulated methanogenesis in the presence of sulfate, and [14C]methylamine was rapidly converted to 14CH4 and 14CO2 in freshly collected marsh sediment. Acetate, hydrogen, or methionine additions did not stimulate methanogenesis. [methyl-14C]methionine and [2-14C]acetate were converted to 14CO2 and not to 14CH4 in fresh sediment. No reduction of 14CO2 to 14CH4 occurred in fresh sediment. Molybdate, an inhibitor of sulfate reduction, inhibited [2-14C]acetate metabolism by 98.5%. Fluoracetate, an inhibitor of acetate metabolism, inhibited sulfate reduction by 61%. These results suggest that acetate is a major electron donor for sulfate reduction in marine sediments. In the presence of high concentrations of sulfate, methane may be derived from novel substrates such as methylamine. 相似文献
9.
Stephen H. Zinder 《FEMS microbiology letters》1986,38(4):243-250
[U-14C]Glucose, added carrier-free to sludge from a thermophilic anaerobic bioreactor being fed a lignocellulose waste, was rapidly turned over with less than one-third of the original radiolabel remaining as glucose after 5 s of incubation. The primary labeled products found were [14C]acetate and 14CO2, which were in a ratio near 2:1. Further incubation resulted in the disappearance of [14C]acetate and the appearance of an equivalent amount of label as 14CH4 and 14CO2. No significant production of [14C]propionate, butyrate, lactate, or ethanol was detected from [14C]glucose, even if these potential intermediates (unlabeled) were added to the sludge at a concentration of 1 mM to trap any label entering their pools. Addition of 0.8 atm (80 kPa) of H2 to the headspace over sludge resulted in some accumulation of [14C]lactate and a corresponding decrease in [14C]acetate produced from [14C]glucose. Production of [14C]propionate, butyrate and ethanol were still not significant in the presence of H2. Incubation of sludge for 1 h in the presence of hydrogen resulted in increases in the lactate and formate concentrations, but not those of propionate, butyrate, or ethanol. These results demonstrate that glucose was metabolized directly to acetate, CO2, and H2 by the microbial populations in the bioreactor with little carbon from glucose flowing through other intermediates, indicating a high degree of coupling between glucose fermentation and hydrogen uptake. The short-term response of these microbial populations to elevated H2 partial pressures was to increase lactate production. 相似文献
10.
Tolbutamide partially inhibited the growth but increased the glycogen content of Tetrahymena pyriformis in logarithmically growing cultures. Tolbutamide slightly increased 14CO2 production from [1-14C] and [6-14HC] glucose and [2-14C] pyruvate, but had little effect on the oxidation of [1-14C] acetate when any of these substrates were added to the proteose-peptone medium in which the cells had been grown. Measurement of 14CO2 production from [1-14C] and [2-I4C]-glyoxylate showed that this substrate was primarily oxidized via the glyoxylate cycle, with little if any oxidation occurring via the peroxisomal glyoxylate oxidase. Addition of tolbutamide inhibited the glyoxylate cycle as indicated by a marked reduction in label appearing in CO2 and in glycogen from labeled acetate. In control cells, addition of acetate strongly inhibited the oxidation of [2-14C]-pyruvate whereas addition of pyruvate had little effect on the oxidation of [1-14C]-acetate. Acetate was more effective than pyruvate in preventing the growth inhibitory and glycogen-increasing effects of tolbutamide. The data suggest that one effect of tolbutamide may be to interfere with the transfer of isocitrate and acetyl CoA across mitochondrial membranes. 相似文献
11.
The labeling pattern of the sugar moieties of 1-kestose after in vivo pulse labeling with 14CO2 was not the same as that after in vitro labeling with 14C-sucrose. The two fructosyl residues of 1-kestose had similar specific radioactivities after in vitro synthesis, but after in vivo radiolabeling the specific radioactivity of the terminal fructosyl moiety was significantly less than the internal fructosyl moiety. Evidence is presented that the uneven specific radioactivity of in vivo radiolabeling results from enzymatic transfer of terminal fructosyl residue from 1-kestose to sucrose. 相似文献
12.
Acetylcholine Synthesis and CO2 Production from Variously Labeled Glucose in Rat Brain Slices and Synaptosomes 总被引:4,自引:4,他引:0
Abstract: The molecular basis of the close linkage between oxidative metabolism and acetylcholine (ACh) synthesis is still unclear. We studied this problem in slices and synaptosomes by measurement of ACh synthesis from [U-14C]glucose, and 14CO2 production from [3,4-14C]- and [2-14C]glucose, an index of glucose decarboxylation by the pyruvate dehydrogenase complex (PDH) and the enzymes of the Krebs cycle, respectively. We examined both under conditions that either inhibited (low O2 or antimycin) or stimulated (2,4- dinitrophenol [DNP] or 35 mm -K+) 14CO2 production from [2-14C]- or [3,4-14C]glucose. Incorporation of [U-14C]glucose into ACh was reduced under low O2 and by antimycin or DNP (by 51-93%) and stimulated by 35 mm -K+ (by 30-60%). Under all of these conditions, ACh synthesis and the decarboxylation of [3,4-14C]- and [2-14C]glucose were linearly related (r= 0.741 and 0.579, respectively). The difference in the rate of 14CO2 production from [3,4-14C]- and [2-14C]glucose was used as a measure of the amount of glucose that was not oxidatively decarboxylated (efflux). We found that efflux was reduced (low 02 and antimycin), unchanged (DNP in slices), or increased (DNP in synaptosomes and K+ stimulation in slices) compared with control values under 100% O2. ACh synthesis and efflux were more closely related (r= 0.860) than ACh synthesis and 14CO2 production from variously labeled glucoses. 相似文献
13.
The effects of glucose (10 mm), glycerol (3 mm), and lactate/pyruvate (10 mm) on the incorporation of 3H from 3H2O into fatty acids were studied in isolated hepatocytes prepared from chow-fed female rats. Lactate/pyruvate markedly increased lipogenic rates, while glucose and glycerol did not significantly affect rates of lipogenesis. In cells incubated with lactate/pyruvate plus glycerol, the increase in 3H incorporation was greater than observed with lactate/pyruvate alone. In hepatocytes isolated from 24-h starved rats, lactate/pyruvate again increased de novo fatty acid synthesis to a greater extent than either glucose or glycerol. Glycerol significantly increased lipogenesis compared to the endogenous rates and when incubated with lactate/pyruvate produced an increase above lactate/pyruvate alone. (?)-Hydroxycitrate, a potent inhibitor of ATP-citrate lyase (EC 4.1.3.8), and agaric acid, an inhibitor of tricarboxylate anion translocation, were studied in hepatocytes to determine their effects on lipogenesis by measuring 3H2O, [1-14C]acetate, and [2-14C]lactate incorporation into fatty acids. 3H incorporation into fatty acids was markedly inhibited by both inhibitors with agaric acid (60 μm) producing the greater inhibition. (?)-Hydroxycitrate (2 mm) increased acetate incorporation into fatty acids from [1-14C]acetate and agaric acid produced a strong inhibitory effect. Combined effects of (?)-hydroxycitrate and agaric acid on lipogenesis from [1-14C]acetate showed an inhibitory response to a lesser extent than with agaric acid alone. With substrate concentrations of acetate present, there was no significant increase in rates of lipogenesis from [1-14C]acetate and the increase previously observed with (?)-hydroxycitrate alone was minimized. Agaric acid significantly inhibited fatty acid synthesis from acetate in the presence of exogenous substrate, but the effect was decreased in comparison to rates with only endogenous substrate present. With [2-14C]lactate as the lipogenic precursor, agaric acid and (?)-hydroxycitrate strongly inhibited fatty acid synthesis. However, agaric acid despite its lower concentration (60 μm vs 2 mm) was twice as effective as (?)-hydroxycitrate. A similar pattern was observed when substrate concentrations of lactate/pyruvate (10 mm) were added to the incubations. When (?)-hydroxycitrate and agaric acid were simultaneously incubated in the presence of endogenous substrate, there was an additive effect of the inhibitors on decreasing fatty acid synthesis. Results are discussed in relation to the origin of substrate for hepatic lipogenesis and whether specific metabolites increase lipogenic rates. 相似文献
14.
Abstract— The oxidation of l -[U-14C]leucine and l -[l-14C]leucine at varying concentrations from 0.1 to 5mM to CO2 and the incorporation into cerebral lipids and proteins by brain slices from 1-week old rats were markedly stimulated by glucose. Although the addition of S mM-dl -3-hydroxybutyrate had no effect on the metabolism of [U-14C]leucine by brain slices from suckling rats, the stimulatory effects of glucose on the metabolism of l -[U-14C]leucine were markedly reduced in the presence of dl -3-hydroxybutyrate. The stimulatory effect of glucose on leucine oxidation was, however, not observed in adult rat brain. Furthermore, the incorporation of leucine-carbon into cerebral lipids and proteins was also very low in the adult brain. The incorporation of l -[U-14C]leucine into cerebral lipids by cortex slices was higher during the first 2 postnatal weeks, which then declined to the adult level. During this time span, the oxidation of l -[U-14C]leucine to CO2 remained relatively unchanged. The incorporation in vivo of D-3-hydroxy[3-14C]butyrate into cerebral lipids was markedly decreased by acute hyperleucinemia induced by injecting leucine into 9-day old rats. In in vitro experiments, 5 mM-leucine had no effect on the oxidation of [U-14C]glucose to CO2 or its incorporation into lipids by brain slices from 1-week old rats. However, 5 mM-leucine inhibited the oxidation of d -3-hydroxy-[3-14C]butyrate, [3-14C]acetoacetate and [1-14C]acetate to CO2 by brain slices, but their incorporation into cerebral lipids was not affected by leucine. In contrast 2-oxo-4-methylvalerate, a deaminated metabolite of leucine, markedly inhibited both the oxidation to CO2 and the incorporation into lipids of labelled glucose, ketone bodies and acetate by cortex slices from 1-week old rats. These findings suggest that the reduction in the incorporation in vivo of d -3-hydroxy[3-14C]butyrate into cerebral lipids in rats injected with leucine is most likely caused by 2-oxo-4-methylvalerate formed from leucine. Since the concentrations of leucine and 2-oxo-4-methylvalerate in plasma of untreated patients with maple-syrup urine disease are markedly elevated, our findings are compatible with the possibility that an alteration in the metabolism of glucose and ketone bodies in the brain may contribute to the pathophysiology of this disease. 相似文献
15.
1. Rats were starved for 48hr. or fed for 1 week on a high-fat or a high-carbohydrate diet. The effects of these dietary alterations on the rate of production of 14CO2 from trace amounts of [U-14C]glucose, [1-14C]palmitate or [1-14C]acetate administered intravenously were studied. 2. The oxidation of [14C]glucose was most rapid in the carbohydrate-fed condition and was decreased significantly and to the same extent after starvation and after feeding with fat. 3. Under all dietary regimes studied the maximum rate of elimination of 14CO2 from [14C]palmitate occurred within a few minutes after injection, but considerably more was oxidized after starvation and feeding with fat than after feeding with carbohydrate. 4. Alterations in diet had no effect on the oxidation and high recovery of administered [14C]acetate as 14CO2. 5. Graphical analysis showed the presence of several exponential components in the 14CO2-elimination curves. 6. In all studies a marked similarity in oxidative pattern was noted between the starved and the fat-fed rat. 相似文献
16.
Differences in paths of carbon flow have been found in soils of the tall (TS) and short (SS) Spartina alterniflora marshes of Sapelo Island, Ga. Gaseous end products of [U-14C]glucose metabolism were 14CO2 and 14CH4 in the SS region and primarily 14CO2 in the TS region. Sulfate concentration did not demonstrably affect glucose catabolism or the distribution of end products in either zone. [U-14C]acetate was converted to 14CO2 and 14CH4 in the SS soils and almost exclusively to 14CO2 in the TS soils. Sulfate concentration did not affect acetate metabolism in the SS soils; however, a noticeable effect of sulfate dilution was seen in TS soils. Sulfate dilution in TS samples resulted in increased methane formation. Total glucose and acetate metabolism were similar in TS and SS soils despite differences in end products. A microbial community characterized by fermentative/sulfate-reducing processes has developed in TS soils as opposed to the fermentative/methanogenic/sulfate-reducing community found in SS soils. 相似文献
17.
Galactose, sucrose, and glucose (50 millimolar) applied to tobacco leaf discs (Nicotiana tabacum L. cv `Xanthi') during a prolonged incubation (5-6 d) markedly stimulated ethylene production which, in turn, could be inhibited by aminoethoxyvinylglycine (2-amino-4-(2′-aminoethoxy)-trans-3-butenoic acid) (AVG) or Co2+ ions. These three tested sugars also stimulated the conversion of l-[3,4-14C]methionine to [14C]1-amino-cyclopropane-1-carboxylic acid (ACC) and to [14C]ethylene, thus indicating that the carbohydrates-stimulated ethylene production proceeds from methionine via the ACC pathway. Sucrose concentrations above 25 mm considerably enhanced ACC-dependent ethylene production, and this enhancement was related to the increased respiratory carbon dioxide. However, sucrose by itself could directly promote the step of ACC conversion to ethylene, since low sucrose concentrations (1-25 mm) enhanced ACC-dependent ethylene production also in the presence of 15% CO2. 相似文献
18.
The relative efficiency of incorporation of the exogenously supplied primary precursors [2-14C]acetate, [U-14C]glucose and [U-14C]sucrose into essential oil was determined in the immature leaves of threeCymbopogon species(C. martinii,C. winterianus andC. flexuosus). Acetate was most efficiently incorporated into essential oil inC. winterianus andC. flexuosus, whereas glucose was the best precursor inC. martinii. The observations are consistent when expressed as radioactivity [Bq] of essential oil per leaf, as percent incorporation or moles of precursors utilized for essential oil synthesis. Thus, there is selectivity in the efficiency of precursor utilization for the oil synthesis inCymbopogon species. 相似文献
19.
Muller AP Rotta LN Kawano C Leszczinski DN Schweigert ID Londero LG Gravina FS da Silveira CK de Souza CG Battu CE Gonçalves CA de Souza DO Perry ML 《Neurochemical research》2006,31(3):417-422
We studied the effect of different concentrations of 2-deoxy-d-glucose on the l-[U-14C]leucine, l-[1-14C]leucine and [1-14C]glycine metabolism in slices of cerebral cortex of 10-day-old rats. 2-deoxy-d-glucose since 0.5 mM concentration has inhibited significantly the protein synthesis from l-[U-14C]leucine and from [1-14C]glycine in relation to the medium containing only Krebs Ringer bicarbonate. Potassium 8.0 mM in incubation medium did not stimulate the protein synthesis compared to the medium containing 2.7 mM, and at 50 mM diminishes more than 2.5 times the protein synthesis compared to the other concentration. Only at the concentration of 5.0 mM, 2-deoxy-d-glucose inhibited the CO2 production and lipid synthesis from l-[U-14C] leucine. This compound did not inhibit either CO2 production, or lipid synthesis from [1-14C]glycine. Lactate at 10 mM and glucose 5.0 mM did not revert the inhibitory effect of 2-deoxy-d-glucose on the protein synthesis from l-[U-14C]leucine. 2-deoxy-d-glucose at 2.0 mM did not show any effect either on CO2 production, or on lipid synthesis from l-[U-14C]lactate 10 mM and glucose 5.0 mM. 相似文献
20.
SYNOPSIS. The growth of Tetrahymena pyriformis strain HSM was strongly inhibited by 4-pentenoic acid. Supplementing the medium with acetate reversed the growth inhibition, but pyruvate was ineffective. Glycogen content was much lower in cells grown with 4-pentenoic acid than in controls; this effect was not reversed by acetate or by pyruvate. There was little effect of 4-pentenoic acid on the incorporation of label from [1-14C]acetate, [2-14C]glycerol, [1-34]ribose, [U-14C]fructose, or [1-14C]glucose into CO2, but incorporation of label into glycogen was inhibited, the strongest inhibition being on acetate and the weakest (~ 20%) on ribose, fructose, and glucose. A 3-compartment model for quantitation of labeled acetyl CoA fluxes was shown to be applicable to Tetrahymena grown in the presence of 4-pentenoic acid, and experiments were performed to establish the flux of [1-14C]acetyl CoA into glycogen, lipids, CO2, glutamate, and alanine. It was evident from the results of these experiments that 4-pentenoic acid did not appreciably inhibit β-oxidation or lipogenesis, but markedly decreased the glyconeogenic flux of labeled acetyl-CoA from the peroxismal and outer mitochondrial compartments. At least 2 mechanisms have been proposed for the action of 4-pentenoic acid: (a) reduction of the levels of acetyl CoA or free CoA and (b) direct inhibition of enzymes by 4-pentenoyl CoA or its metabolites. Although 4-pentenoic acid has little effect on acetyl-CoA metabolism in the inner mitochondrial compartment, the present data suggest that the flux through the outer mitochondrial compartment of acetyl-CoA derived from pyruvate is inhibited largely by the first, and that the glyconeogenic flux of acetyl-CoA is inhibited largely by the 2nd mechanism. 相似文献