Glucose 6-phosphate dehydrogenase (G6PD) was purified from Streptomyces aureofaciens and inactivated with butanedione and diethylpyrocarbonate. Incubation of the enzyme with butanedione resulted in a rapid activity loss (80%) within 5 min, followed by a slow phase using a molar ratio to enzyme concentration of 100. Fluorescence studies showed a conformational change in the butanedione-modified ...

A characteristic spectral emission is observed in vegetation chlorophyll under excitation by solar radiation. This emission, known as solar-induced chlorophyll fluorescence, occurs in the red and near infra-red spectral regions. In this paper a new methodology for the estimation of solar-induced chlorophyll fluorescence from spaceborne and airborne sensors is presented. The fluorescence signal ...

Chlorophyll a fluorescence can be used as an early stress indicator. Fluorescence is also connected to photosynthesis so it can be proposed for global monitoring of vegetation status from a satellite platform. Nevertheless, the correct interpretation of fluorescence requires accurate physical models. The spectral shape of the leaf fluorescence free of any re-absorption effect plays a key role i...

(-)-Epigallocatechin 3-O-gallate (EGCG) a molecule found in green tea and known for a plethora of bioactive properties is an inhibitor of heat shock protein 90 (HSP90), a protein of interest as a target for cancer and neuroprotection. Determination of the spectral properties of EGCG fluorescence in environments similar to those of binding sites found in proteins provides an important tool to di...

Hyperspectral confocal fluorescence imaging provides the opportunity to obtain individual fluorescence emission spectra in small ( approximately 0.03-microm(3)) volumes. Using multivariate curve resolution, individual fluorescence components can be resolved, and their intensities can be calculated. Here we localize, in vivo, photosynthesis-related pigments (chlorophylls, phycobilins, and carote...

Trypsin (E.C.3.4.21.4) is a serine protease commonly used in proteomics for digestion of proteins. In the present study, the effect of nano-TiO2 on the conformation and catalytic activity of trypsin were studied. The thermal denaturation of trypsin has been investigated in the presence and absence of nano-TiO2 over the temperature range (293-373 K) at pH 3.0 and 7.25, using temperature scanning...

Fluorescence based methods are increasingly being used for the analysis of crude oils because they offer high speed, low cost, non-contact, and non-destructive testing options. The fluorescence of crude oils is due to the presence of a wide range of cyclic aromatic compounds, with the intensity and temporal behaviour of this fluorescence being directly related to chemical composition. In partic...

glucose 6-phosphate dehydrogenase (g6pd) from streptomyces aureofaciens was purified and denatured in 6 m urea. denaturation led to complete dissociation of the enzyme into its inactive monomers, 98% loss of the enzyme activity, about 30% decrease in the protein fluorescence and a 10 nm red shift in the emission maximum. dilution of urea-denatured enzyme resulted in regaining of the enzyme acti...

a new sensitive, simple and rapid method for determination of methotrexate (mtx) was developed based on quenching effects of mtx on the fluorescence intensity of tb3+-1,10-phenanthroline complex. the fluorescence intensity was measured with excitation wavelength of 300 nm and emission wavelength of 545 nm and the quenched fluorescence intensity is proportional to the concentration of mtx in tris...