Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method is described for the preparation of spheroplasts in high yield from Schizosaccharomyces pombe, by treating cells grown in the presence of glucose and deoxyglucose with snail digestive enzymes. Gentle disruption of such spheroplasts yielded homogenates, from which marker enzymes for nuclei (NAD pyrophosphorylase) and mitochondria (cytochrome c oxidase activity and spectroscopically-detectable cytochromes a + a3) could be quantitatively sedimented by low-speed centrifugation. In contrast to previous findings with Saccharomyces carlsbergensis, cytochrome c oxidase and another mitochondrial enzyme, succinate dehydrogenase, were completely sedimentable by zonal centrifugation in sucrose gradients in the presence of either 2 mM-MgCl2 or 0-4 mM-EDTA. Mitochondria were apparently smaller and of lower buoyant density in gradients containing EDTA. The bulk of the total units of malate dehydrogenase and NADH; cytochrome c oxidoreductase sedimented with mitochondria, whereas NADPH: cytochrome c oxidoreductase was located in fractions containing no mitochondria. The distributions of mitochondrial enzymes were heterogeneous in populations of mitochondria separated on the basis of size or density. The possible origins of mitochondrial heterogeneity in extracts of S. pombe are discussed with special reference to changes in the enzyme activities of cells during the cell cycle.
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PMID:Fractionation by differential and zonal centrifugation of spheroplasts prepared from a glucose-repressed fission yeast Schizosaccharomyces pombe 972h-. 18 Feb 35

Proteolytic activities in bovine adrenocortical mitochondria were investigated using [14C-methyl]casein as a substrate. Washed mitochondria showed a low proteolytic activity at pH 7.5 or 8.2. ATP (5 mM) plus MgCl2 (7.5 mM) stimulated the proteolysis 9 times at pH 8.2. It was further demonstrated unequivocally by various approaches that the ATP-dependent proteolytic activity localizes in mitochondrial matrix. The activity of the solubilized protease was sensitive to N-ethylmaleimide, mersalyl acid, phenylmethylsulfonyl fluoride, o-vanadate, m-vanadate, vanadyl sulfate, and quercetin but not by oligomycin and ouabain. The ATP-dependent proteolytic activity was eluted at the position of 650,000 daltons on an Ultrogel AcA 22 column as a single symmetrical peak. The gel-filtered enzyme showed high specificity to ATP. GTP and UTP partially substituted ATP. ADP, AMP, tripolyphosphate, alpha, beta-methylene ATP, and beta, gamma-methylene ATP had little or no stimulating activity. ATP did not stimulate the activity in the absence of MgCl2. We measured ATP-dependent proteolytic activities in mitochondrial fractions from several tissues in rat and bovine. Adrenal cortex was one of the tissues of highest activity. In addition, we investigated the effect of adrenal atrophy on the ATP-dependent protease activity in rat adrenal. The ATP-dependent protease activity/adrenal decreased by dexamethasone treatment. The extent of the decrease was similar to that of cytochrome oxidase and succinate dehydrogenase, but smaller than that of cytochrome P-450.
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PMID:ATP-dependent protease in bovine adrenal cortex. Tissue specificity, subcellular localization, and partial characterization. 298 96

An intrinsic 22 kDa polypeptide is associated with the O2-evolving Photosystem II core complex in a variety of green plants, although it does not appear to be required for O2 evolution. Digestion of thylakoid membranes and isolated Photosystem II preparations with trypsin, followed by immunoblotting using spinach anti-22 kDa antibodies, leads to two observations: (1) the domain between the 2nd and 3rd transmembrane helices of the 22 kDa protein is stromally exposed, and (2) only in a reaction center complex preparation, lacking the chlorophyll a/b-light harvesting complex II, is there extensive proteolytic cleavage of the 22 kDa protein. We also found that after, but not prior to, selective extraction of the 22 and 10 kDa proteins from Photosystem II membranes, the chlorophyll a/b-light harvesting complex II can be separated from the Photosystem II reaction center core by precipitation with MgCl2. This result suggests that the 22 kDa polypeptide is located between the Photosystem II reaction center polypeptides and light-harvesting complex II; it is possible that the protein serves as a link between the two protein complexes. The presence of the 22 kDa protein in several species was also examined by immunoblotting with polyclonal spinach anti-22 kDa antibodies.
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PMID:Topological studies of spinach 22 kDa protein of Photosystem II. 780 50