Oxidative stress and reactive oxygen species (ROS) such as hydrogen peroxide (H2O2), which is detoxified by catalase, are implicated in fetal death and birth defects, but embryonic levels of catalase are only about 5% of adult activity, and its protective role is unknown. Our approach involved the use of mice genetically modified to either: (1) express low levels of endogenous catalase (acatala...

I t is now a well established fact tha t liver catalase activity is diminished in tumor-bearing hosts which carry any one of a variety of types of cancer. Since the tumor may be located at a distance from the liver, the effect is systemic (2, 3, 9, 13, 19, 20, 24). Nakahara and Fukuoka (26, 27) have reported tha t the agent responsible for the depression of liver catalase is found abundantly in...

In environmental studies, some biological responses, known as biomarkers, have been used as a powerful bioassay tool for more than four decades. Disparity between enzyme activity and mRNA abundance leads to correlation equivocality, which makes the application of biomarkers for environmental risk assessment more complicated. This study investigates this disparity in the case of catalase when us...

renal ischemia-reperfusion (ir) injury is a common problem in kidney transplantation. there is increasing evidence about the role of the reactive oxygen species (ros) in these injuries and endogenous antioxidants seem to have an important role in decreasing the renal tissue injury. the aim of this study was to investigate the effects of kidney ir on renal antioxidant enzymes activity such as ca...

PURPOSE Oxidative stress is generated through imbalance between composing and decomposing of reactive oxygen species (ROS). This kind of stress was rarely discussed in connection with foreign protein production in Escherichia coli. Effect of cytoplasmic recombinant protein expression on Hydrogen peroxide concentration and catalase activity was previously reported. In comparison with cytoplasm, ...

An attempt was made to find out the nature of catalase coritained in the red cell, especially in the ghost, For this the red cell ghost isolated were washed several times with CO2-saturated water or deionized water and the catalase activity per gram protein of the ghost was estimated. It was found that despite several washings, the catalase activity/gram protein of the ghost do not decrease as ...

Catalase enzyme from red poppy (Papaver rhoeas) plant was immobilized covalently with glutaraldehyde onto chitosan particles. The changes in the kinetic properties of the immobilized and free red poppy catalase were determined. The Km values were found to be 26 and 33 mM for free and immobilized red poppy catalase on chitosan. Furthermore, various characteristics of free and immobilized red pop...

We had previously isolated a facultatively anaerobic hyperthermophilic archaeon, Pyrobaculum calidifontis strain VA1. Here, we found that strain VA1, when grown under aerobic conditions, harbors high catalase activity. The catalase was purified 91-fold from crude extracts and displayed a specific activity of 23,500 U/mg at 70 degrees C. The enzyme exhibited a K(m) value of 170 mM toward H(2)O(2...

In order to know the precise quantity of catalase protein in acatalasemic and hypocatalasemic blood, immunological studies were conducted using hemolysates or acetone extracts of those blood as antigen. 1) The ratio of catalase contained in normal, hypocatalasemic and acatalasemic blood, calculated from precipitates produced in the reaction between catalase antibody and hemolysates was 1.0 : 0....