The mechanism by which bi-and trivalent cations affect human liver phosphatidatephosphohydrolase (PAP) activity was investigated. Bivalent cations up to 1 mM increased PAP activity whereas at higher concentrations the activity of the enzyme decreased. The stimulatory concentration for trivalent cations such as Al3+ and Cr3+, however, was much lower being 2 m M and 1 m M, respectively. All catio...

l-asparaginase has lots of medical and industrial applications. ever since l-asparaginase anti-tumor activity was first demonstrated, its production using microbial systems has attracted considerable attention owing to their cost-effective and eco-friendly nature. the aim of this study is to obtain l-asparaginase producing bacteria and determining the enzyme activity. samples were picked up fro...

biochemical characteristics of α-amylase in the digestive system and head glands of cryptolaemus montrouzieri, a key predator of citrus mealybug, planococcus citri (pseudococcidae), were studied. the major isoform of α-amylase with the same molecular weight was detected in both gut and head glands loaded on polyacrylamide-starch gel electrophoresis. moreover, a minor band with much lower intens...

the effect of epinephrine on phosphatidate phosphohydrolase (pap) activity of isolated human hepatocytes was studied. epineprine inhibited the enzyme activity progressively at concentrations above 0.1 µm, reaching a maximum inhibition of 64.5% at 100 µm concentration. inclusion of alprenolol, a β-receptor blocker, in the incubation mixture abolished the inhibitory effect of epinephrine on pap, ...

The activity of one of the metabolizing enzymes of - aminobutyric acid, (GABA), was determined in mouse hypothalamus after peripheral injections of cholecystokinin-8 (CCK-8) and caerulein (CLN). The activity of this rate-limiting enzyme, L-glutamic acid decarboxylase, (GAD), did not change thirty minutes after peripheral injections of either CCK-8 or CLN in doses of 50g/kg body weight. Howeve...

Enzymes Immobilization onto different types of the substrate could be helpful in various applicationsof biomedical devices and biosensors. Enzyme activity and stability could be affected by support andmethod of immobilization. In this study, the silver metal foam was successfully synthesized by thesoft-shell method and then was coated with silica. Then, glucose oxidase (GOx) immobilized on nonc...

Background: Blood is permanently exposed to oxidation stress and therefore has a high antioxidants capacity. Many different factors increasing the demand for the antioxidant capacity can be observed in the stored blood of donors. Consequently, damage to erythrocytes by free radicals may occur. So it is useful to control the alternation of anti-oxidant enzymes in stored blood at different days o...

antibodies directed against the enzyme glutamic acid decarboxylase (gad) are believed to be the main cause of destruction of pancreatic islet cells in type i (insulin dependent) diabetes mellitus. the enzyme was found both in the brain and pancreatic beta cells. although similarities in identity of gad in human and rat brain have been demonstrated, little is known about the interaction between ...