Experiments are described further indicating that 02-resistant photosynthesis observed in a tobacco (Nicotiana tabacum) mutant with enhanced catalase activity is associated with decreased photorespiration under conditions of high photorespiration relative to net photosynthesis. The effects on net photosynthesis of (a) increasing O2 concentrations from 1% to 42% at low CO2 (250 microliters CO2 p...

By CHEV KIDS0N C ATALASE is an enzyme found in most body tissues which has the capacity to release molecular oxygen from hydrogen peroxide ( H202 ) . It is concerned with peroxidation of substrates such as alcohol, phenol, formate and formaldehyde.1 Catalase in blood has aroused considerable interest, the enzyme content being higher than that in other tissues except liver.2 Most studies have co...

In an investigation (Sherstinsky, 1951; Yaniv, 1951) of the factors governing the virulence of Pasteurella tularensis (Bacterium tularense), the correlation between the activity of catalase and virulence was studied. This line of approach was suggested by the fact that in the Brucella group (Huddleson and Stahl, 1943) and in PasteureUa pestis (Rockenmacher, 1949) high virulence appears to be as...

Catalase activities have been evaluated in testes and caput and cauda epididymis of Wistar rats fed on zinc deficient diet for 2 and 4 weeks. The enzyme activity has been measured as chromic acetate formed by heating of dichromate (in acetic acid) in presence of H(2) O(2) with perchromic acid as an unstable intermediate. Observed non-significant increase in catalase activity in testes as well a...

Winder, Frank G. (Trinity College, Dublin, Ireland). Peroxidatic activity of mycobacteria and relation to catalase. J. Bacteriol. 92:413-417. 1966.-Catalase from Mycobacterium smegmatis was purified about 50-fold. All fractions showed a ratio of peroxidatic activity to catalatic activity approximately the same as that of the crude extract, a ratio only about four times that given by catalase fr...

Adenine deaminase (ADE) from the amidohydrolase superfamily (AHS) of enzymes catalyzes the conversion of adenine to hypoxanthine and ammonia. Enzyme isolated from Escherichia coli was largely inactive toward the deamination of adenine. Molecular weight determinations by mass spectrometry provided evidence that multiple histidine and methionine residues were oxygenated. When iron was sequestered...

A novel flow-injection assay (FIA) system with a double line for catalase activity was constructed in which an oxidase is immobilized and the substrate is continuously pumped to reduce the dissolved oxygen and to generate a given level of hydrogen peroxide. The catalase in a sample decomposed the hydrogen peroxide, and thus the increase in dissolved oxygen dependent on the activity was amperome...

Catalase-peroxidases are bifunctional peroxidases exhibiting an overwhelming catalase activity and a substantial peroxidase activity. Here we present a kinetic study of the formation and reduction of the key intermediate compound I by probing the role of the conserved tryptophan at the distal haem cavity site. Two wild-type proteins and three mutants of Synechocystis catalase-peroxidase (W122A ...

By CHEV KIDS0N C ATALASE is an enzyme found in most body tissues which has the capacity to release molecular oxygen from hydrogen peroxide ( H202 ) . It is concerned with peroxidation of substrates such as alcohol, phenol, formate and formaldehyde.1 Catalase in blood has aroused considerable interest, the enzyme content being higher than that in other tissues except liver.2 Most studies have co...

In a variety of disorders, endothelial cells are exposed to high levels of oxidants, generated within the cells and/or consequent to local inflammation. In the context of the sensitivity of endothelial cells to oxidant stress, particularly related to H2O2, we have designed a replication deficient recombinant adenovirus containing the human catalase cDNA (AdCL) to transfer the catalase cDNA to t...