Although modern statistical computing will often be the method of choice for analyzing kinetic data, graphic methods provide an important supplement that ought not to be neglected. Residual plots, or plots of differences between observed and calculated values against variables not expected to be correlated with these differences, permit a rapid judgment of whether data have been correctly inter...

A criticism [Cornish-Bowden (1976) Biochem. J. 159, 167] of an algebraic method for deriving steady-state rate equations [Indge & Childs (1976) Biochem. J. 155, 567-570] is theoretically founded.

Michaelis and Menten's mechanism for enzymatic catalysis is remarkable both in its simplicity and its wide applicability. The extension for reversible processes, as done by Haldane, makes it even more relevant as most enzymes catalyze reactions that are reversible in nature and carry in vivo flux in both directions. Here, we decompose the reversible Michaelis-Menten equation into three terms, e...

most of the biological phenomena are influenced by intermolecular recognition and interaction. thus, understanding the thermodynamics of biomacromolecule ligand interaction is a very interesting area in biochemistry and biotechnology. one of the most powerful techniques to obtain precise information about the energetics of (bio) molecules binding to other biological macromolecules is isothermal...

abstract        background and objective: peroxidases catalyze protein oxidation and lipid peroxidation. the activity of these enzymes in nerve cells is involved in causing disorders such as alzheimer's and parkinson's disease. this study investigated the effect of citrus aurantium, foeniculum vulgare and rosmarinus officinalis essential oils on activity of peroxidase enzyme.       me...

Accurate label-free methods or assays to obtain the initial reaction rates have significant importance in fundamental studies of enzymes and in application-oriented high throughput screening of enzyme activity. Here we introduce a label-free approach for obtaining initial rates of enzyme activity from heat measurements, which we name initial rate calorimetry (IrCal). This approach is based on o...

In a conformational nonequilibrium steady state (cNESS), enzyme turnover is modulated by the underlying conformational dynamics. On the basis of a discrete kinetic network model, we use an integrated probability flux balance method to derive the cNESS turnover rate for a conformation-modulated enzymatic reaction. The traditional Michaelis-Menten (MM) rate equation is extended to a generalized f...

We discuss techniques for measuring myeloperoxidase activity cytochemically in isolated polymorphonuclear neutrophils. We have used a sophisticated scanning microdensitometer as a reference device and compared results obtained by Zeiss Ultraphot III B and Reichert Zetopan microscopes with those of the scanning microdensitometer. We made both end-point and kinetic measurements, using conventiona...

Polymersome-based bioluminescent nanocompartment to achieve enzyme protection and switch kinetics produce a persistent light signal.

The aim of this study was the use of fish waste hydrolysate (FWH) as a substrate for alkaline protease production using isolated Bacillus sp. in a batch system. Then the fermentation kinetics of enzyme production was studied. The results show that with the addition of FWH to the fermentation medium with a final concentration of 4% (optimal concentration), alkaline protease value reached a maxim...