Several rat and mouse hepatomas and the liver and kidneys of the host animals were assayed for catalase activity. Little or no activity could be demonstrated in the subcutaneously transplanted Novikoff hepatoma, Hepatoma LC18, and Hepatoma 3683 of rats, and in a number of transplanted hepatomas of mice and hamsters. A relatively high activity was found, however, in the transplanted Hepatoma 512...

The specific catalase activity of human diploid cell strains increases with progressive growth of the culture, and falls again following subculture. Although the increase is small, it is readily demonstrable, and is exponential with time. The response of catalase activity to progressive growth of the culture was studied in three abnormal human cell lines. A diploid cell strain, developed from a...

in this research, catalase activity and leaf chlorophyll stability of satsuma mandarin on some citrus rootstocks under waterlogging condition were studied. experiment was conducted as factorial with randomized complete blocks and 6 replications. the first factor, include 7 soils from east mazandaran and the second factor included 7 different citrus rootstocks: 1. sour orange, 2. swingle citrome...

Catalase-peroxidase (KatG) is an enzyme capable of utilizing both catalase and peroxidase activity to break down hydrogen peroxide. Catalase activity by the enzyme generally dominates, but peroxidatic electron donors have been shown to stimulate catalase activity, likely by rescuing catalase-inactive intermediates resulting from off-pathway electron transfer. To investigate tryptophan 438 as a ...

Since oxygen-free polymorphonuclear neutrophils (PMN) cannot kill Staphylococcus aureus normally, the usual mechanisms for PMN bactericidal activity probably involve hydrogen peroxide or superoxide. Catalase can destroy hydrogen peroxide, and superoxide dismutase breaks down superoxide. Experiments were performed to study the influence of these enzymes (which are found in staphylococci) on viru...

The effects of heat on catalase from Staphylococcus aureus lysates were examined. Catalase activity increased with increasing concentrations of potassium phosphate buffer, when heated at temperatures between 50 and 65 degrees C for 10 min. Inactivation of catalase by NaCl during heating was demonstrated. Extended heating of S. aureus cells at 52 degrees C resulted in a slight decrease in catala...

Catalase (H2O2:H2O2 oxidoreductase, E.C. 1.11.1.6) is a ubiquitous antioxidant metalloenzyme located primarily within the peroxisomes of most mammalian cells. In C57BL/6 mice, liver catalase activity levels are approximately 60% of the levels found in most other mouse strains, including C3H/HeJ (1). Ganschow and Schimke (2) demonstrated using immunological techniques that equal numbers of catal...

BACKGROUND (MRL)-lpr/lpr mice spontaneously develop autoimmune disease characterized by arthritis and glomerulonephritis. Nitric oxide is postulated to play a role in the disease pathogenesis, as mice treated with the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine (NMMA) show markedly reduced manifestations of the disease. The purpose of this study was to examine the role of peroxyn...