Distribution Of Catalase Activity Research Articles

Study on CAT activity of tomato leaf cells under salt stress based on microhyperspectral imaging and transfer learning algorithm

Salt stress easily leads to oxidative stress and promotes the catalase (CAT) response in tomato leaves. For the changes in catalase activity in leaf subcells, there is a need for a visual in situ detection method and mechanism analysis. This paper, taking catalase in leaf subcells under salt stress as the starting point, describes the use of microscopic hyperspectral imaging technology to dynamically detect and study catalase activity from a microscopic perspective, and lay the theoretical foundation for exploring the detection limit of catalase activity under salt stress. In this study, a total of 298 microscopic images were obtained under different concentrations of salt stress (0 g/L, 1 g/L, 2 g/L, 3 g/L) in the spectral range of 400–1000 nm. With the increase in salt solution concentration and the advancement of the growth period, the CAT activity value increased. Regions of interest were extracted according to the reflectance of the samples, and the model was established by combining CAT activity. The characteristic wavelength was extracted by five methods (SPA, IVISSA, IRFJ, GAPLSR and CARS), and four models (PLSR, PCR, CNN and LSSVM) were established according to the characteristic wavelengths. The results show that the random sampling (RS) method was better for the selection samples of the correction set and prediction set. Raw wavelengths are optimized as the pretreatment method. The partial least-squares regression model based on the IRFJ method is the best, and the coefficient of correlation (Rp) and root mean square error of the prediction set (RMSEP) are 0.81 and 58.03 U/g, respectively. According to the ratio of microarea area to the area of the macroscopic tomato leaf slice, the Rp and RMSEP of the prediction model for the detection of microarea cells are 0.71 and 23.00 U/g, respectively. Finally, the optimal model was used for quantitative visualization analysis of CAT activity in tomato leaves, and the distribution of CAT activity was consistent with its color trend. The results show that it is feasible to detect the CAT activity in tomato leaves by microhyperspectral imaging combined with stoichiometry.

Isolation and biochemical characterization of peroxisomes from cultured rat glial cells.

Peroxisomes are now recognized to play important cellular functions and its dysfunction leads to a group of neurological disorders. This study reports peroxisomal enzyme activities in cultured glial cells and peroxisomes isolated from cultured oligodendrocytes and C6 glial cells. Peroxisomal enzyme activities were found to be higher in oligodendroglial cells than in astrocytes or mixed glial cells. We also developed a method for the isolation of peroxisomes from glial cells by a combination of differential and density gradient centrifugation techniques. Peroxisomes from oligodendrocytes in nycodenz gradient were isolated at a density of 1.165 g/ml +/- 0.011. Activities of dihydroxyacetone phosphate acyl transferase, beta-oxidation of lignoceric acid and alpha-oxidation of phytanic acid were almost exclusively associated with the distribution of catalase activity (a marker enzyme for peroxisomes) in the gradient. This protocol should be a resource for studies designed to investigate the structure and function of peroxisomes in brain cells.

The Distribution of Catalase Activity, Isozyme Protein, and Transcript in the Tissues of the Developing Maize Seedling

The catalase activity, CAT-2 and CAT-3 isozyme protein levels, and the steady-state mRNA levels for each of the three catalase genes were determined in the scutellum, root, epicotyl, and leaf of the developing maize (Zea mays L.) seedling. Catalase activity was highest in the scutellum, with 10-fold lower enzyme activity in the leaf and epicotyl. Very low levels of catalase activity were found in the root. The highest levels of CAT-2 protein were found in the scutellum, with about 10-fold lower levels in the green leaf. CAT-2 protein was present in trace amounts early in root development and no CAT-2 protein was detected in the epicotyl. Shortly after germination, CAT-3 protein was present at high levels in both the epicotyl and green leaf. With development, the amount of CAT-3 protein decreased slowly in the epicotyl and rapidly in the green leaf. Low levels of this isozyme were detected in the scutellum and root. The Cat1 transcript accumulated to low levels in all four tissues during the 14 day developmental period. High levels of the Cat2 transcript were found in the scutellum, with moderate levels of the mRNA in the green leaf. The Cat2 transcript levels were very low in the root and epicotyl. While the Cat3 mRNA level in the scutellum was low, high levels of the Cat3 transcript were detected in the root, epicotyl, and leaf. There was a positive correlation between the accumulation of a catalase isozyme and its transcript, indicating that the tissue specificity of maize catalase gene expression was regulated pretranslationally.

Radiosensitivity and Biological Properties of Tumours

SummaryIntracellular distribution of catalase activity after x-irradiation was determined in two types of mouse mammary epithelial tumours, H and DBrB, in a spindle-cell tumour (DBAG) and in a plasma-cell tumour (Adj-PC-5). Livers and kidneys were used for comparison. Catalase activities were assayed from three sub-cellular fractions, mitochondrial, microsomal and cell-sap.A decrease in catalase activity in the mitochondrial fraction with a concomitant increase in the cell-sap fraction was noted after x-irradiation. The extent of the release of catalase activity from the mitochondrial to the cell-sap fraction differed between the various tissues. The greatest release after x-irradiation was noted in the epithelial tumour (H). This occurrence is obscured in the G and DBrB tumours due to the spontaneous release of this enzyme because of homogenization damage to the boundary membrane in which catalase is encased. It is inferred that the shift in catalase activity from the mitochondrial to the cell-sap fracti...

Cellular distribution of catalase activity in red cells of homozygous and heterozygous cases of acatalasia.

Es wird ein Verfahren beschrieben, welches im Blutausstrich katalasehaltige und katalasefreie Erythrocyten zu unterscheiden erlaubt. Dieses beruht auf der sehr ungleichen Methamoglobinbildung bei Inkubierung der Zellen mit Glucose und Glucoseoxidase. Es wird nachgewiesen, dass im Blut homozygoter Defekttrager 0,5-1% aller Erythrocyten einen anscheinend normalen Katalasegehalt aufweisen. Im Blut heterozygoter Defekttrager konnten keine Anhaltspunkte fur das Bestehen zweier Zellpopulationen von verschiedener Katalaseaktivitat gefunden werden.