Invertase immobilized on magnetic diatomaceous earth nanoparticles (mDE-APTES-invertase) with high sucrolytic activity was obtained by an easy and low-cost method. An experimental design was carried out to investigate the best immobilization conditions and it allowed obtaining an immobilized derivative with a residual specific activity equal to 92.5%. Then, a second experimental design selected...

Leaf senescence is the final stage of leaf development in which the nutrients invested in the leaf are remobilized to other parts of the plant. Whereas senescence is accompanied by a decline in leaf cytokinin content, exogenous application of cytokinins or an increase of the endogenous concentration delays senescence and causes nutrient mobilization. The finding that extracellular invertase and...

The repertoire of hydrolytic enzymes natively secreted by the filamentous fungus Ashbya (Eremothecium) gossypii has been poorly explored. Here, an invertase secreted by this flavinogenic fungus was for the first time molecularly and functionally characterized. Invertase activity was detected in A. gossypii culture supernatants and cell-associated fractions. Extracellular invertase migrated in a...

Vacuoles were isolated from freshly cut slices of the storage roots of beetroot (Beta vulgaris), and from slices that had been washed in aerated water for 1-3 days. The unique vacuolar location of betanin permitted the use of a correlative method to determine whether sucrose and acid invertase were located in the vacuoles. The specific content (the activity of the enzyme or amount of substrate ...

The localization of invertase, a key enzyme in plant carbohydrate metabolism, has been established in several higher plants, but there are no reports of it in ferns. The aim of the present work was to establish the localization of the previously reported acid invertase activity of Pteris deflexa in fronds tissues and to compare the findings with invertase localization in higher plants. Acid inv...

Early POC diagnosis of cancer is demonstrated by using multi-invertase conjugated microsphere labels and a personal glucose sensor (PGS) transducer. The invertase, which catalyzes the hydrolysis of sucrose to glucose, enables the PGS to detect target analytes beyond glucose, and the numerous invertase labels involved in each antibody-antigen binding event lead to significantly amplified PGS rea...

The SUC2 gene of yeast (Saccharomyces) encodes two forms of invertase: a secreted, glycosylated form, the synthesis of which is regulated by glucose repression, and an intracellular, nonglycosylated enzyme that is produced constitutively. The SUC2 gene has been cloned and shown to encode two RNAs (1.8 and 1.9 kb) that differ at their 5' ends. The stable level of the larger RNA is regulated by g...

Among the numerous molecular and physiological modifications induced by water deficit, one of the earliest events observed in maize mature leaves subjected to water deprivation was a strong enhancement of acid vacuolar invertase activity, which occurred before the classical reduction in gas exchange due to stomatal closure. The increase in invertase activity coincided with the rapid accumulatio...

This paper reports a novel approach in the electrode immobilization of an enzyme, invertase, by electrochemical polymerization of pyrrole in the presence of enzyme. The polypyrrole/invertase and polyamide/polypyrrole/invertase electrodes were constructed by the entrapment of enzyme in conducting matrices during electrochemical polymerization of pyrrole. This study involves the preparation and c...

The activity of yeast invertase as a function of oxidation-reduction potential has been investigated using a large number of oxidants and reductants. The activity is constant over the range of E(h) from -270 to +600 mv., but above E(h) = +600 mv. there is a sharp decrease in activity reaching 0 at E(h) = +1,000 mv. The inhibiting action of strong oxidants is upon the enzyme rather than on the s...