Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.21 (beta-glucosidase)
3,280 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A complex neuropathological study of two cases of Niemann-Pick disease (NPD) type C (NPDC) revealed some novel features in the chemical pathology of the neuronal storage. Lipid histochemistry showed the presence of a lipid which met the criteria of a neuronal glycosphingolipid. Sphingomyelin (SM) was not detected in the neurones in any of the regions examined. Lipid chemical analysis of total extracts and of partially purified lysosomal fraction of the brain cortex showed markedly increased levels of neutral ceramide hexosides especially of glucosylceramide and ceramide dihexoside (mostly of its slower band). Phospholipids were not significantly increased. Monosialogangliosides GM2 and GM3 were increased only slightly. The storage process displayed the well known fine structure and was accompanied by a marked secondary increase in some lysosomal enzyme activities. There was neuroaxonal dystrophy (NAD) of considerable intensity and extent. Many spheroids contained masses of degenerated organelles and neurofilaments in various proportions and displayed variable activities of acid phosphatase, nonspecific esterase and dehydrogenases. There was marked brain atrophy accompanied in one case by severe demyelination. Enzyme studies revealed partial decrease of sphingomyelinase (SMase) and beta-glucosidase activities in cultured fibroblasts, as well as lack of cathodic SMase activity on isoelectric focusing. No defects of these enzymes were found in the brain samples. The findings are regarded as significant since they indicate a biochemical defect in which SM is not primarily involved and which may thus be fundamentally different from that in type A of NPD.
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PMID:Niemann-Pick disease type C. Study on the nature of the cerebral storage process. 401 80

Antisera were raised to a partially purified preparation of human liver hexosaminidase and to highly purified preparations of hexosaminidase isoenzymes A and B. All the antisera precipitated the enzyme in an enzymically active form, which could be located on immunodiffusion and immunoelectrophoretic gels by using a histochemical substrate. The antisera to the purified isoenzymes were shown to react with hexosaminidase from human liver, kidney, brain and spleen, but did not cross-react with human liver beta-glucosidase, beta-galactosidase, alpha-mannosidase, beta-xylosidase, arylsulphatase or acid phosphatase. Hexosaminidases A and B were immunologically identical. The immunological properties of the hexosaminidases from livers of patients with three types of GM(2)-gangliosidoses were closely similar. No evidence could be found for cross-reacting material in enzyme-deficient states.
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PMID:Immunological properties of N-acetyl-beta-D-glucosaminidase of normal human liver and of GM2-gangliosidosis liver. 419 85

A method is described for the rapid and efficient isolation of phagocytic vesicles from large scale cultures of Acanthamoeba castellanii (Neff) that have been incubated with polystyrene latex beads. Cells were allowed to phagocytose latex beads for 30 min and then were homogenized, and the phagocytic vesicles were isolated by one centrifugation through several layers of sucrose. Identity and purity of the phagocytic vesicles were determined by electron microscopy, chemical analyses, and assays of acid phosphatase, alpha- and beta-glucosidase, and reduced nicotinamide adenine dinucleotide dehydrogenase. When phagocytosis was allowed to occur for longer periods the phagocytic vesicles appeared to fuse with each other and perhaps with digestive vacuoles. The resultant vesicles which contained many beads were heavier than those which consisted of only one bead or a few beads with a closely applied membrane. Ultrasonication ruptured the isolated vesicles, and the membranes could then be isolated in 30-50% yield based on phospholipid analysis. These membranes were essentially free of acid hydrolases and, presumably, other soluble proteins, as was also indicated by their low ratio of protein to phospholipid. The membranes have been prepared both as closed vesicles and as open sheets.
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PMID:Phagocytosis of latex beads by Acahamoeba castellanii (Neff). 3. Isolation of the phagocytic vesicles and their membranes. 430 54

Smooth muscle cells were dissociated from normal rabbit aorta by incubating the tissue in Hanks' solution containing elastase, collagenase, and hyaluronidase. The isolated cells contained significant amounts of the following acid hydrolases: N-acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, beta-glucosidase, acid phosphatase, and cathepsins C and D. The cells were disrupted and fractionated by isopycnic centrifugation on sucrose density gradients in the Beaufay automatic zonal rotor. Lysosomes with a modal density of 1.16 were identified by the distribution of these acid hydrolases and by the latency of N-acetyl-beta-glucosaminidase and beta-galactosidase. Other particulate enzymes studied in these sucrose gradients included cytochrome oxidase and monoamine oxidase (mitochondria), 5'-nucleotidase and leucyl-beta-naphthylamidase (plasma membrane), and catalase (? peroxisome). This microanalytical subcellular fractionation technique is applicable to the study of milligram quantities of many other tissues, both normal and pathological.
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PMID:Lysosomes of the arterial wall. I. Isolation and subcellular fractionation of cells from normal rabbit aorta. 434 42

1. The specific activities of beta-N-acetylglucosaminidase, acid phosphatase, alpha-mannosidase, beta-glucosidase, UDP-glucose pyrophosphorylase and alkaline phosphatase have been determined in myxamoebae of the cellular slime mould Dictyostelium discoideum Ax-2 grown on different media and in different phases of the growth cycle. 2. Variations in enzymic composition occur with changes in growth medium and phase of the growth cycle. 3. The intracellular location of the enzymes studied has been determined. 4. Two enzymes, beta-N-acetylglucosaminidase and alpha-mannosidase, are not only synthesized preferentially as the myxamoebae enter the stationary phase of growth but they are also excreted. The excretion process appears to be specific, because other enzymes that occur in the same intracellular fraction are not excreted.
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PMID:Enzyme synthesis in myxamoebae of the cellular slime mould Dictyostelium discoideum during growth in axenic culture. 467 68

1. Myxamoebae of the cellular slime mould Dictyostelium discoideum Ax-2 were grown on different media, and were harvested either in the stationary or exponential phases of the growth cycle to yield samples of myxamoebae differing in enzymic composition. 2. Morphogenesis and cell differentiation phenomena in D. discoideum appear to be similar in myxamoebae grown and harvested under different conditions. 3. The specific activity of the enzymes beta-N-acetylglucosaminidase, acid phosphatase, alpha-mannosidase, beta-glucosidase and alkaline phosphatase have been determined during cell differentiation of myxamoebae grown and harvested under different conditions. 4. The pattern of synthesis of these enzymes, all of which have been claimed to be part of the ;developmental programme', either remains unaffected despite the origin of the myxamoebae (alkaline phosphatase) or is qualitatively similar but quantitatively affected (acid phosphatase, beta-glucosidase) or is both qualitatively and quantitatively affected by changes in the myxamoebae (alpha-mannosidase, beta-N-acetylglucosaminidase). 5. The implications of these results for the concept of a ;developmental programme' are discussed.
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PMID:Enzyme synthesis in the cellular slime mould Dictyostelium discoideum during the differentiation of myxamoebae grown axenically. 467 69

Toxicity tests on Culex pipiens fatigans with propoxur (o-isopropoxyphenyl methylcarbamate) and carbofuran (2,2-dimethyl-2,3-dihydrobenzofuranyl-7-methylcarbamate) indicated that both compounds are fast-acting insecticides. Transfer of treated larvae to fresh water results in their partial recovery from knockdown.Propoxur is metabolized by resistant and susceptible larvae by their homogenate-reduced nicotinamide-adenine dinucleotide phosphate (NADPH(2)) enzyme system and by the microsome-plus-soluble fraction of mouse-liver extracts to at least 10 organosoluble metabolites with the isopropoxy group intact. The major metabolites, which are primarily hydroxylation products or the result of degradation of these products, have tentatively been identified as: acetone plus o-hydroxyphenyl methylcarbamate, 2-isopropoxy-5-hydroxyphenyl methylcarbamate, 2-isopropoxyphenyl carbamate, and 2-isopropoxyphenyl N-hydroxymethylcarbamate. Upon incubation of water-soluble products from treated larvae with beta-glucosidase, beta-glucuronidase, aryl sulfatase and acid phosphatase, the conjugates are hydrolysed, liberating mainly hydroxylated carbamates.The results indicate that slower absorption as well as faster detoxification by hydroxylation mechanisms, together with conjugation with polar molecules and elimination, are major factors in resistance of mosquito larvae to substituted-aryl methylcarbamate insecticides.
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PMID:Carbamate resistance in mosquitos. The metabolism of propoxur by susceptible and resistant larvae of Culex pipiens fatigans. 531 55

The exposure of cultivated mouse macrophages to sucrose (0.009-0.03 M) leads to the formation of large phase- and electron-lucent, acid phosphatase-positive vacuoles in the perinuclear region. The vacuolization process and the uptake of sucrose-(14)C is blocked by inhibitors of pinocytosis and stimulated by calf serum in the medium. These results suggest the uptake of sucrose by pinocytosis and its subsequent segregation and storage in secondary lysosomes. The addition of sucrose also increases the total content of three macrophage lysosomal hydrolases. The addition of invertase to the environment of sucrose-laden macrophages leads to the prompt shrinkage of the sucrose-containing lysosomes. This is accompanied by the intracellular hydrolysis of sucrose to fructose and glucose residues which are promptly excreted into the medium. The uptake of invertase, as indicated by the shrinkage of sucrose-containing vacuoles, is blocked by inhibitors of pinocytosis. No effect was noted when invertase was added to macrophages laden with Ficoll, a polysucrose which is not hydrolyzed by the enzyme. The influence of other carbohydrates was then investigated. Monosaccharides with molecular weights up to 220 did not produce vacuolization. However, a certain number of di-, tri-, and tetrasaccharides produced vacuolization identical with that of sucrose. Each of the disaccharides which produced vacuolization was resistant to the complement of macrophage hexosidases, whereas those that were ineffective were degraded by either macrophage or serum enzymes. The addition of beta-glucosidase to cellobiose-laden macrophages resulted in the shrinkage of vacuoles but did not alter the vacuoles of sucrose containing cells. The ability of small, neutral carbohydrates to produce lysosomal swelling is dependent upon both molecular weight and their resistance to lysosomal hydrolases.
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PMID:The uptake, storage, and intracellular hydrolysis of carbohydrates by macrophages. 578 68

Brock, Thomas D. (Indiana University, Bloomington). Biochemical and cellular changes occurring during conjugation in Hansenula wingei. J. Bacteriol. 90:1019-1025. 1954.-A technique has been devised for deagglutinating mixed populations of conjugating cells so as to be able to visualize microscopically early stages of the conjugation process. A cell can form a conjugation tube only when in contact with a cell of opposite mating type, but may do so even if the mate is unresponsive or ultraviolet-inactivated. Cell fusion occurs, however, only when both cells are able to form conjugation tubes in a region of contact. Fusion begins almost as soon as the two cells begin to form protuberances, and long before any dissolution of cell-wall material between the cells occurs. A cell which has conjugated in one region of its cell wall is still able to conjugate with another cell in another region, so that triply and quadruply conjugated cells are occasionally formed. There is no significant net increase in deoxyribonucleic acid, ribonucleic acid, protein, or carbohydrate which might be related to the conjugation process, because any minor changes that occur in these components are also detected when cells of only one mating type are incubated or when the conjugation process is inhibited with the antibiotic cycloheximide. Changes in activity of beta-1,3-glucanase (with laminarin as substrate) and beta-1,6-glucanase (with pustulan as substrate) have been measured during the conjugation process, in addition to changes in the activity of several control enzymes which would not be expected to be related to the conjugation process. Significant increases in invertase (sucrase), laminarinase, and pustulanase were detected, and minimal increases occurred in beta-glucosidase and acid phosphatase. However, these same increases were also observed in controls involving only one mating type; thus, these increases are probably not related to the conjugation process, but may be a result of other processes which probably occur during incubation in the conjugation medium.
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PMID:Biochemical and cellular changes occuring during conjugation in Hansenula wingei. 584 91

In a standard growing medium, the specific activities of acid-phosphatase, beta-galactosidase and beta-glucosidase of Physarum polycephalum increase during the growth of the culture. The decrease of the pH of the culture medium during the growth has no effect on the variations of these hydrolase activities. In a glucose-starved medium, the specific activity of beta-galactosidase increases up to 350% of its initial value in 24 h, whereas the specific activities of acid phosphatase and beta-glucosidase stay near their minimal level.
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PMID:[Regulation of various hydrolase activities in the myxomycete Physarum polycephalum]. 616 4


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