Acid hydrolases of the sporogonic stage ofPlasmodium, berghei nigeriensis

Abstract The results show that incubation of gastric mucosal cells from rat at pH ~4.5 or in the presence of aspirin is associated with a specific increase in the activity of some acid-hydrolases. Intracellular glycoproteins, isolated by non-degradative techniques from rat or dog fundic mucosal cells, were found to be potential bio-substrates for these acid-hydrolyses. This may suggest that cleavage of the carbohydrate moieties of the intracellular and mucosal cell wall glycoproteins is a fundamental step in the development of gastric ulceration. A model for gastric lesions is proposed and discussed in the light of the results obtained.

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Effects of antimycin A and 2-deoxyglucose on secretion in human platelets. Differential inhibition of the secretion of acid hydrolases and adenine nucleotides

Biochemical Journal ◽

10.1042/bj1820413 ◽

1979 ◽

Vol 182 (2) ◽

pp. 413-419 ◽

Cited By ~ 14

Author(s):

Holm Holmsen ◽

Linda Robkin ◽

H. James Day

Keyword(s):

Shape Change ◽

Adenine Nucleotides ◽

Human Platelets ◽

Dense Granule ◽

Metabolic Inhibitors ◽

Antimycin A ◽

Acid Hydrolase ◽

Acid Hydrolases ◽

Dense Granule Secretion ◽

Granule Secretion

1. Shape change, aggregation and secretion of dense-granule constituents in platelets differ in their dependence on cellular energy metabolism. The possibility that such a difference also exists between secretion of dense-granule constituents and acid hydrolases was investigated. 2. Human platelets were incubated with [14C]adenine in plasma, and then washed and resuspended in salt solutions. The effects of incubating the cells with antimycin A and 2-deoxyglucose on the concentrations of [14C]ATP, ADP, AMP, IMP and inosine plus hypoxanthine and on thrombin-induced secretion of ATP plus ADP and acid hydrolases were studied. The metabolic inhibitors only affected 14C-labelled nucleotides, whereas thrombin only liberated unlabelled ATP and ADP. 3. The extent of secretion decreased progressively with time during incubation with the metabolic inhibitors. At any time the secretion of acid hydrolases, β-N-acetylglucosaminidase, β-glucuronidase and β-galactosidase was inhibited to a greater extent than secretion of ATP plus ADP (dense-granule secretion). 4. Incubation with the metabolic inhibitors shifted the log (dose)–response relationship to higher thrombin concentrations, and with a greater shift for acid hydrolase secretion than for dense-granule secretion. 5. Antimycin, when present alone, caused a marked decrease in the rate of acid hydrolase secretion, but had no effect on dense-granule secretion. 6. These results further support the view that acid hydrolase secretion and dense-granule secretion are separate processes with different requirements for ATP energy. Acid hydrolase secretion, but not dense-granule secretion, appears to depend on a simultaneous rapid generation of ATP, which can be accomplished by oxidative, but not by glycolytic, ATP production.

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Analytical subcellular fractionation of needle-biopsy specimens from human liver

Biochemical Journal ◽

10.1042/bj1740435 ◽

1978 ◽

Vol 174 (2) ◽

pp. 435-446 ◽

Cited By ~ 39

Author(s):

T J Peters ◽

C A Seymour

Keyword(s):

Endoplasmic Reticulum ◽

Plasma Membrane ◽

Density Gradient ◽

Needle Biopsy ◽

Human Liver ◽

Resolving Power ◽

Equilibrium Density ◽

Marker Enzyme ◽

Acid Hydrolases ◽

Biopsy Specimens

1. Fragments (2-20 mg wet wt.) of closed needle-biopsy specimens from human liver were disrupted in iso-osmotic sucrose and subjected to low-speed centrifugation. The supernatant was layered on a linear sucrose-density gradient in the Beaufay small-volume automatic zonal rotor. The following organelles, with equilibrium densities (g/ml) and principal marker enzyme shown in parentheses, were resolved: plasma membrane (1.12-1.14; 5′-nucleotidase); lysosomes (1.15-1.20; N-acetyl-beta-glucosaminidase); mitochondria (1.20; malate dehydrogenase); endoplasmic reticulum (1.17-1.21; neutral alpha-glucosidase); peroxisomes (1.22-1.24; catalase). 2. The distribution of particulate alkaline phosphatase and, to a lesser degree, leucine 2-naphthylamidase followed that of 5′-nucleotidase. gamma-Glutamyltransferase was associated with membranes of significantly higher equilibrium density than was 5′-nucleotidase. 3. The distribution of 12 acid hydrolases was determined in the density-gradient fractions. beta-Glucosidase had a predominantly cytosolic localization, but the other enzymes showed a broad distribution of activity throughout the gradient. Evidence was presented for two populations of lysosomes with equilibrium densities of 1.15 and 1.20 g/ml, but containing differing amounts of each enzyme. Further evidence of lysosomal heterogeneity was demonstrated by studying the distribution of isoenzymes of hexosaminidase and of acid phosphatase. 4. The resolving power of the centrifugation procedure can be further enhanced with membrane perturbants. Digitonin (0.12 mM) selectively disrupted lysosomes, markedly increased the equilibrium density of plasma-membrane components and lowered the density of the endoplasmic reticulum, but did not affect the mitochondria or peroxisomes. Pyrophosphate (15 mM) selectively lowered the equilibrium density of the endoplasmic reticulum.

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Bafilomycin A1 inhibits the targeting of lysosomal acid hydrolases in cultured hepatocytes

Biochemical and Biophysical Research Communications ◽

10.1016/0006-291x(91)91823-u ◽

1991 ◽

Vol 178 (1) ◽

pp. 369-377 ◽

Cited By ~ 30

Author(s):

Kimimitsu Oda ◽

Yukio Nishimura ◽

Yukio Ikehara ◽

Keitaro Kato

Keyword(s):

Bafilomycin A1 ◽

Cultured Hepatocytes ◽

Acid Hydrolases ◽

Lysosomal Acid

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Acid hydrolases in the bovine corneal epithelium

Graefe s Archive for Clinical and Experimental Ophthalmology ◽

10.1007/bf02173365 ◽

1986 ◽

Vol 224 (5) ◽

pp. 467-468 ◽

Cited By ~ 2

Author(s):

T. Shiono ◽

S. Hayasaka ◽

K. Mizuno

Keyword(s):

Corneal Epithelium ◽

Acid Hydrolases

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Developmental Patterns of Acid Hydrolases during Differentiation of Fetal Mouse Skin

Experimental Biology and Medicine ◽

10.3181/00379727-152-39453 ◽

1976 ◽

Vol 152 (4) ◽

pp. 618-620 ◽

Cited By ~ 3

Author(s):

M. J. C. Im ◽

J. E. Hoopes

Keyword(s):

Mouse Skin ◽

Acid Hydrolases ◽

Developmental Patterns ◽

Fetal Mouse

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Transcriptome and Proteome Expression Analysis of the Metabolism of Amino Acids by the FungusAspergillus oryzaein Fermented Soy Sauce

BioMed Research International ◽

10.1155/2015/456802 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Guozhong Zhao ◽

Yunping Yao ◽

Chunling Wang ◽

Fengwei Tian ◽

Xiaoming Liu ◽

...

Keyword(s):

Amino Acids ◽

Gel Electrophoresis ◽

Metabolic Pathways ◽

Soy Sauce ◽

Flavor Compounds ◽

Acid Hydrolases ◽

Conserved Genes ◽

2D Gel ◽

Dipeptidyl Aminopeptidase ◽

Proteome Expression

Amino acids comprise the majority of the flavor compounds in soy sauce. A portion of these amino acids are formed from the biosynthesis and metabolism of the fungusAspergillus oryzae; however, the metabolic pathways leading to the formation of these amino acids inA. oryzaeremain largely unknown. We sequenced the transcriptomes ofA. oryzae100-8 andA. oryzae3.042 under similar soy sauce fermentation conditions. 2D gel electrophoresis was also used to find some differences in protein expression. We found that many amino acid hydrolases (endopeptidases, aminopeptidases, and X-pro-dipeptidyl aminopeptidase) were expressed at much higher levels (mostly greater than double) inA. oryzae100-8 than inA. oryzae3.042. Our results indicated that glutamate dehydrogenase may activate the metabolism of amino acids. We also found that the expression levels of some genes changed simultaneously in the metabolic pathways of tyrosine and leucine and that these conserved genes may modulate the function of the metabolic pathway. Such variation in the metabolic pathways of amino acids is important as it can significantly alter the flavor of fermented soy sauce.

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