The heat-labile T class of mycobacterial catalase exhibits peroxidase activity with some substrates. Most species of mycobacteria produce T-catalase, which is serologically characterized by a combination of shared epitopes and unique, species-specific epitopes. Antibodies to T-catalases from Mycobacterium tuberculosis, Mycobacterium avium, and Mycobacterium intracellulare have been cross absorb...

It has been claimed that the sole H(2)O(2)-scavenging system in the cyanobacterium Synechococcus sp. PCC 7942 is a cytosolic catalase-peroxidase. We have measured in vivo activity of a light-dependent peroxidase in Synechococcus sp. PCC 7942 and UTEX 625. The addition of small amounts of H(2)O(2) (2.5 microM) to illuminated cells caused photochemical quenching (qP) of chlorophyll fluorescence t...

Rat liver mitochondria are much more susceptible to protein oxidation induced by paraquat than plant mitochondria. The unsaturated index and the peroxidizability index are higher in rat than in potato tuber. The levels of superoxide dismutase and glutathione reductase are concurrent with the different sensitivities to paraquat, with higher activities in plant mitochondria. However, glutathione ...

Effect of hydroalcoholic extract T. bispinosa (TB) was studied on fluorescence product and biochemical parameter like lipid peroxidation, catalase activity and glutathione peroxidase activity in the brain of female albino mice. Ageing was accelerated by the treatment of 0.5 ml 5% D-galactose for 15 days. This resulted in increased fluorescence product, increase lipid peroxidation and decrease a...

We demonstrate that Co(3)O(4) nanoparticles (NPs) exhibit intrinsic peroxidase-like activity and catalase-like activity. The peroxidase-like activity of the Co(3)O(4) NPs originates from their ability of electron transfer between reducing substrates and H(2)O(2), not from ˙OH radical generated. As peroxidase mimetics, Co(3)O(4) NPs were used for colorimetric determination of H(2)O(2) and glucose.

Under increased oxygen tensions, Thermus aquaticus exhibited a lag period in growth of 80 min, during which the specific activities of catalase, peroxidase, and superoxide dismutase increased. Methyl viologen increased the lag period, decreased the maximum population density, increased cell lysis, and induced catalase and superoxide dismutase. Methyl viologen, in conjunction with chloramphenico...

Studies of the pH decreases that accompany the formation of Compound I from ox liver catalase and peroxoacetic acid in unbuffered systems imply that 1 mol of acetic acid is released/mol of catalase ferrihaem Compound I formed. This result is consistent with results previously obtained (Schonbaum & Lo, 1972) for the formation of peroxidase Compound I by using peroxo acid substrate.

The major aim of this work was to investigate how alcohol-induced oxidative stress in combined chemotherapy changes the metabolic function of the liver in experimental animals. This research was conducted to establish how bromocriptine, haloperidol and azithromycin, applied to the experimental model, affected the antioxidative status of the liver. The following parameters were determined: reduc...

Oxidation of methionine, 4-(methylthio)-2-oxobutyric acid (KMB), or 1-aminocyclopropane carbonic acid (ACC) are indicator reactions for activated oxygen species such as singlet oxygen (1O2), OH.-radical like oxidants, superoxide anion (O2.-), hydrogen peroxide (H2O2) or activated hemo-iron complexes like peroxidase- or catalase-"compound I". Methionine is oxidized by OH. as well as by 1O2 formi...

Heme-containing catalases and catalase-peroxidases catalyze the dismutation of hydrogen peroxide as their predominant catalytic activity, but in addition, individual enzymes support low levels of peroxidase and oxidase activities, produce superoxide, and activate isoniazid as an antitubercular drug. The recent report of a heme enzyme with catalase, peroxidase and penicillin oxidase activities i...