Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.3.1 (citrate synthase)
 4,488 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Considered are our own data and those found in literature on the properties of yeast mutants impaired in their ability to utilize methanol as sole carbon and energy source; hypotheses about the role of alcohol oxidase and citrate synthase in biogenesis of peroxisomes are proposed. It has been proved that formaldehyde reductase participates in the control of the formaldehyde level in the cell. Properties of mutants defective in the catabolite repression and inactivation of enzymes of methanol metabolism are described. The existence of several autonomous mechanisms of the catabolite repression of alcohol oxidase has been shown. It has been found, that the induction of glyoxysomal enzymes of C2-metabolism is repressed by methanol in the ecr1 mutant of Pichia pinus with the affected repression of alcohol oxidase by ethanol. Data are presented on the regulatory properties of the recently discovered acidification system of the medium induced by methanol. Such acidification occurs due to symport extrusion of protons and formate anions from the cells.
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PMID:Genetic control of methanol utilization in yeasts. 306 50

Ignicoccus hospitalis is an autotrophic hyperthermophilic archaeon that serves as a host for another parasitic/symbiotic archaeon, Nanoarchaeum equitans. In this study, the biosynthetic pathways of I. hospitalis were investigated by in vitro enzymatic analyses, in vivo (13)C-labeling experiments, and genomic analyses. Our results suggest the operation of a so far unknown pathway of autotrophic CO(2) fixation that starts from acetyl-coenzyme A (CoA). The cyclic regeneration of acetyl-CoA, the primary CO(2) acceptor molecule, has not been clarified yet. In essence, acetyl-CoA is converted into pyruvate via reductive carboxylation by pyruvate-ferredoxin oxidoreductase. Pyruvate-water dikinase converts pyruvate into phosphoenolpyruvate (PEP), which is carboxylated to oxaloacetate by PEP carboxylase. An incomplete citric acid cycle is operating: citrate is synthesized from oxaloacetate and acetyl-CoA by a (re)-specific citrate synthase, whereas a 2-oxoglutarate-oxidizing enzyme is lacking. Further investigations revealed that several special biosynthetic pathways that have recently been described for various archaea are operating. Isoleucine is synthesized via the uncommon citramalate pathway and lysine via the alpha-aminoadipate pathway. Gluconeogenesis is achieved via a reverse Embden-Meyerhof pathway using a novel type of fructose 1,6-bisphosphate aldolase. Pentosephosphates are formed from hexosephosphates via the suggested ribulose-monophosphate pathway, whereby formaldehyde is released from C-1 of hexose. The organism may not contain any sugar-metabolizing pathway. This comprehensive analysis of the central carbon metabolism of I. hospitalis revealed further evidence for the unexpected and unexplored diversity of metabolic pathways within the (hyperthermophilic) archaea.
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PMID:Insights into the autotrophic CO2 fixation pathway of the archaeon Ignicoccus hospitalis: comprehensive analysis of the central carbon metabolism. 1740 Jul 48

These studies were structured with the aim of utilizing emerging technologies in two-dimensional (2D) gel electrophoresis and mass spectrometry to evaluate protein expression changes associated with type 1 diabetes. We reasoned that a broad examination of diabetic tissues at the protein level might open up novel avenues of investigation of the metabolic and signaling pathways that are adversely affected in type 1 diabetes. This study compared the protein expression of the liver, heart, and skeletal muscle of diabetes-prone rats and matched control rats by semiquantitative liquid chromatography-mass spectrometry and differential in-gel 2D gel electrophoresis. Differential expression of 341 proteins in liver, 43 in heart, and 9 (2D gel only) in skeletal muscle was detected. These data were assembled into the relevant metabolic pathways affected primarily in liver. Multiple covalent modifications were also apparent in 2D gel analysis. Several new hypotheses were generated by these data, including mechanisms of net cytosolic protein oxidation, formaldehyde generation by the methionine cycle, and inhibition of carbon substrate oxidation via reduction in citrate synthase and short-chain acyl-CoA dehydrogenase.
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PMID:Proteomic changes associated with diabetes in the BB-DP rat. 1898 54

Methanococcoides burtonii is a cold-adapted methanogenic archaeon from Ace Lake in Antarctica. Methanol and methylamines are the only substrates it can use for carbon and energy. We carried out quantitative proteomics using iTRAQ of M. burtonii cells grown on different substrates (methanol in defined media or trimethylamine in complex media), using techniques that enriched for secreted and membrane proteins in addition to cytoplasmic proteins. By integrating proteomic data with the complete, manually annotated genome sequence of M. burtonii, we were able to gain new insight into methylotrophic metabolism and the effects of methanol on the cell. Metabolic processing of methanol and methylamines is initiated by methyltransferases specific for each substrate, with multiple paralogs for each of the methyltransferases (similar to other members of the Methanosarcinaceae). In M. burtonii, most methyltransferases appear to have distinct roles in the metabolism of methylated substrates, although two methylamine methyltransferases appear to be nonfunctional. One set of methyltransferases for trimethylamine catabolism appears to be membrane associated, potentially providing a mechanism to directly couple trimethylamine uptake to demethylation. Important roles were highlighted for citrate synthase, glutamine synthetase, acetyl-CoA decarbonylase/synthase, and pyruvate synthase in carbon and nitrogen metabolism during growth on methanol. M. burtonii had only a marginal response to the provision of exogenous amino acids (from yeast extract), indicating that it is predisposed to the endogenous synthesis of amino acids. Growth on methanol appeared to cause oxidative stress in the cell, possibly through the formation of reactive nonoxygen species and formaldehyde, and the oxidative inactivation of corrinoid proteins, with the cell responding by elevating the synthesis of universal stress (Usp) proteins, several nucleic acid binding proteins, and a serpin. In addition, changes in levels of cell envelope proteins were linked to counteracting the disruptive solvent effects of methanol on cell membranes. This is the first global proteomic study to examine the effects of different carbon sources on the growth of an obligately methylotrophic methanogen.
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PMID:Global proteomic analysis of the insoluble, soluble, and supernatant fractions of the psychrophilic archaeon Methanococcoides burtonii. Part II: the effect of different methylated growth substrates. 1994 65