Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The hexokinase: fumarase ratios of mitochondria isolated from ten tissues of the rat were determined, and compared with the tissue content of phosphoglucomutase and phosphorylase, taken as representatives of enzymes concerned with glycogen metabolism. A generally inverse relationship was found between the mitochondrial hexokinase: fumarase ratio and phosphoglucomutase levels. The cytochrome: fumarase ratios were relatively invariant in these same mitochondria. The results are interpreted as indicating a specialization of mitochondria, with increased amounts to hexokinase being associated with the mitochondria in tissues exhibiting less dependence on glycogen metabolism, as judged from phosphoglucomutase levels.
Mol Cell Biochem 1977 Nov 25
PMID:An inverse relation between mitochondrial hexokinase content and phosphoglucomutase activity of rat tissues. 60 Feb 70

A rapid switch from a fermentative to a primarily oxidative type of glucose utilization was observed during in vitro differentiation of Trypanosoma brucei STIB348 and EATRO1244 bloodstream to procyclic trypomastigotes. In accordance with previously published reports bloodstream populations produced pyruvate as the major end product of glucose catabolism, together with very small amounts of CO2, succinate and glycerol. During differentiation pyruvate excretion decreased within 48 h to the low levels produced by 28-day procyclic stages. Concomitant with the decline in pyruvate formation, acetate appeared as a new product and the rates of respiratory CO2 increased considerably. The amount of carbon released with these compounds could account for nearly all of the glucose carbon consumed. Rates of glucose utilization and formation of acetate and CO2 in cells differentiated for 48 h were essentially the same as those found in 28-day procyclics. Succinate and glycerol excretion remained low during the entire transformation process, and no significant difference in the pattern and quantities of end products were found between the two trypanosome strains. During trypanosome differentiation the changes in metabolism were associated with marked alterations in enzyme activity levels. Activities of the tricarboxylic acid (TCA) cycle enzymes citrate synthase, isocitrate dehydrogenase (NAD+), succinate dehydrogenase and fumarase were not detectable in bloodstream trypomastigotes but appeared upon differentiation for 24 h. An exception was citrate synthase whose activity was not demonstrable until 48 h postinoculation into culture. After 48 h the majority of the TCA cycle enzyme activities continued to increase steadily until day 28. Pyruvate kinase activity decreased in differentiating cells after 48 h to about 25% of the level found in bloodstream trypomastigotes.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Biochem Parasitol 1991 Mar
PMID:Alterations in Krebs cycle enzyme activities and carbohydrate catabolism in two strains of Trypanosoma brucei during in vitro differentiation of their bloodstream to procyclic stages. 190 88

The RNA polymerase sigma factor sigma H is essential for the onset of endospore formation in Bacillus subtilis. sigma H also is required for several additional stationary-phase-specific responses, including the normal expression of several genes that are required for the development of competence for DNA uptake. It is necessary to identify the genes that are transcribed by sigma H RNA polymerase (E sigma H) in order to understand the role of this sigma factor during the transition from exponential growth to stationary phase. Feavers et al. (Mol. Gen. Genet. 211:465-471, 1988) proposed that citG, the structural gene for fumarase, is transcribed from two promoters, one of which (citGp2 [P2]) may be used by E sigma H. It is likely that the citGp2 promoter is used by E sigma H because we found that this promoter was used accurately in vitro by E sigma H and directed expression of xylE in vivo. This xylE expression was dependent on spo0H, the structural gene for sigma H, and was independent of the citGp1 promoter. Comparison of the nucleotide sequences of several sigma H-dependent promoters showed that these sequences were similar at two regions approximately 10 and 35 base pairs upstream from the start points of transcription. These sequences may signal recognition of these promoters by E sigma H. Primer extension analyses were used to examine transcription from three sigma H-dependent promoters during growth and sporulation. The citGp2 promoter appeared to be active during the middle and late stages of exponential growth, whereas activation of the spoIIA promoter was delayed until after the end of exponential growth. Evidently, promoters used by E sigma H can display different temporal patterns of expression.
 ...
PMID:Sigma H-directed transcription of citG in Bacillus subtilis. 250 22

The level of fumarase activity in Bacillus subtilis depends on the nutritional environment; in rich medium low vegetative levels increase towards the end of the exponential phase, whereas in minimal glucose medium levels are relatively high throughout growth. Analysis of the enzyme levels in spoO mutants has revealed that a functional spoOH gene is required for the efficient expression of fumarase in both media. This highlights a regulatory role for the spoOH gene product not only in control of postexponentially expressed genes, but also during vegetative growth in defined medium. S1 transcript mapping reveals three transcriptional startpoints for the fumarase structural gene (citG) in B. subtilis. The upstream promoter region P1, which appears to contain two transcriptional startpoints, is functional in both Escherichia coli and B. subtilis. Promoter P2, which is located closer to the structural gene, is only functional in B. subtilis. Transcription from this promoter is strictly dependent on a functional spoOH gene; this gene has recently been shown to encode a minor sigma factor.
Mol Gen Genet 1988 Mar
PMID:The regulation of the fumarase (citG) gene of Bacillus subtilis 168. 313 May 45

In Saccharomyces cerevisiae a nuclear recessive mutation, lpd1, which simultaneously abolishes the activities of lipoamide dehydrogenase, 2-oxoglutarate dehydrogenase and pyruvate dehydrogenase has been identified. Strains carrying this mutation can grow on glucose or poorly on ethanol, but are unable to grow on media with glycerol or acetate as carbon source. The mutation does not prevent the formation of other tricarboxylic acid cycle enzymes such as fumarase, NAD+-linked isocitrate dehydrogenase or succinate-cytochrome c oxidoreductase, but these are produced at about 50%-70% of the wild-type levels. The mutation probably affects the structural gene for lipoamide dehydrogenase since the amount of this enzyme in the cell is subject to a gene dosage effect; heterozygous lpd1 diploids produce half the amount of a homozygous wild-type strain. Moreover, a yeast sequence complementing this mutation when present in the cell on a multicopy plasmid leads to marked overproduction of lipoamide dehydrogenase. Homozygous lpd1 diploids were unable to sporulate indicating that some lipoamide dehydrogenase activity is essential for sporulation to occur on acetate.
Mol Gen Genet 1986 Jul
PMID:A mutation affecting lipoamide dehydrogenase, pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase activities in Saccharomyces cerevisiae. 352 55

The intramitochondrial localization of the fumarate reductase, NADPH----NAD transhydrogenase, 'malic' enzyme and fumarase was determined in adult Hymenolepis diminuta. The distribution of marker enzymes for the inner membrane, matrix, intermembrane space and outer membrane of H. diminuta mitochondria simulated that of the corresponding ascarid and mammalian organelles. The electron transport-coupled fumarate reductase and the NADPH----NAD transhydrogenase were components of the inner membrane whereas the 'malic' enzyme and fumarase were in the matrix soluble compartment. Assessments of NADH utilization, malate-dependent NADP reduction and NADPH----NAD transhydrogenation by presumedly intact and disrupted mitochondria supported the localization data. The findings presented indicate that in H. diminuta mitochondria (a) NADPH and fumarate are accumulated within the matrix compartment; (b) transhydrogenation between NADPH and NAD is an event associated with the matrix side of the inner membrane; and (c) electron transport-dependent NADH oxidation and fumarate reduction occur at sites on the matrix side of the inner membrane.
Mol Biochem Parasitol 1985 Nov
PMID:Intramitochondrial localization of fumarate reductase, NADPH----NAD transhydrogenase, 'malic' enzyme and fumarase in adult Hymenolepis diminuta. 406 58

Cells of the aerotolerant anaerobe Giardia lamblia respire in the presence of oxygen. Endogenous respiration is stimulated by glucose but not by other carbohydrates and Krebs cycle intermediates. Endogenous and glucose-stimulated respiration are insensitive to cyanide, malonate, and 2,4-dinitrophenol, but are inhibited by atabrin and iodoacetamide. G. lamblia produces ethanol, acetate and CO2 both aerobically and anaerobically either from endogenous reserves or exogenous glucose. Molecular hydrogen is not produced. The following enzyme activities were detected in homogenates: hexokinase, fructose-biphosphate aldolase, pyruvate kinase, phosphoenolpyruvate carboxykinase, malate dehydrogenase, malate dehydrogenase (decarboxylating), pyruvate synthase, acetyl-CoA synthetase, alcohol dehydrogenase (NADP+), NADH dehydrogenase, NADPH dehydrogenase, NADPH oxidoreductase and superoxide dismutase. The enzymes of energy and carbohydrate metabolism are nonsedimentable (109 000 x g for 30 min). Activities of lactate dehydrogenase, hydrogenase, phosphate acetyltransferase, acetate kinase, citrate synthase, succinate dehydrogenase, fumarate hydratase and catalase were below the limits of detection. The results suggest the occurrence of glycolysis, energy production by substrate level phosphorylation and a flavin, iron-sulfur protein mediated electron transport system as well as the absence of cytochrome mediated oxidative phosphorylation and functional Krebs cycle.
Mol Biochem Parasitol 1980 Mar
PMID:Energy metabolism of the anaerobic protozoon Giardia lamblia. 610 7

The distribution of fumarase and malic enzyme in Ascaris suum muscle mitochondria was investigated by employing digitonin fractionation techniques. The ability of these procedures to resolve the various submitochondrial fractions (intracristal space, inner membrane, matrix and inner membrane-matrix particles) was verified by electron microscopy and the distribution of appropriate marker enzymes. From the data obtained, it is concluded that fumarase in Ascaris muscle mitochondria is located solely within the matrix compartment and is not present within the intracristal space as reported earlier by other authors (Rew and Saz (1974) J. Cell. Biol. 63, 125-135). In agreement with previous findings malic enzyme in the nematode organelle appears to be associated with both soluble compartments. The implications of these findings to the parasites' mitochondrial metabolism are discussed.
Mol Biochem Parasitol 1983 Dec
PMID:The localization of fumarase and malic enzyme in muscle mitochondria of Ascaris suum. 665 45

The enzymes involved in the catabolism of malate namely fumarate reductase, NADH oxidase, "malic" enzyme, succinate dehydrogenase and fumarase as well as NADPH:NAD transhydrogenase, which is involved in the electron transport chain, were studied in Hymenolepis diminuta, a rat intestinal tapeworm. Among cations, K+ had no effect on any enzyme whereas Ca2+ and Mg2+ showed an increase or decrease of varying degrees of different enzyme activities. Most of the compounds, which have been synthesized by the Central Drug Research Institute, Lucknow (India) and found to possess some anthelmintic properties, strongly inhibited the above enzymes except malic enzyme.
Biochem Mol Biol Int 1994 Sep
PMID:Effect of cations and anthelmintics on enzymes of respiratory chains of the cestode Hymenolepis diminuta. 784 34

The yeast mitochondrial and cytosolic isoenzymes of fumarase, which are encoded by a single nuclear gene (FUM1), follow a unique mechanism of protein subcellular localization and distribution. Translation of all FUM1 messages initiates only from the 5'-proximal AUG codon and results in a single translation product that contains the targeting sequence located within the first 32 amino acids of the precursor. All fumarase molecules synthesized in the cell are processed by the mitochondrial matrix signal peptidase; nevertheless, most of the enzyme (80 to 90%) ends up in the cytosol. The translocation and processing of fumarase are cotranslational. We suggest that in Saccharomyces cerevisiae, the single type of initial translation product of the FUM1 gene is first partially translocated, and then a subset of these molecules continues to be fully translocated into the organelle, whereas the rest are folded into an import-incompetent state and are released by the retrograde movement of fumarase into the cytosol.
Mol Cell Biol 1994 Jul
PMID:The single translation product of the FUM1 gene (fumarase) is processed in mitochondria before being distributed between the cytosol and mitochondria in Saccharomyces cerevisiae. 800 76


1 2 3 4 5 6 7 Next >>