Evidence for catalytic dismutation of superoxide by cobalt(II) derivatives of bovine superoxide dismutase in aqueous solution as studied by pulse radiolysis

A direct demonstration of the catalytic action of superoxide dismutase through the use of pulse radiolysis.

Superoxide dismutase catalyzes the decay of 0~~, generated by pulse radiolysis. The enzymatic reaction was 6rst order with respect to enzyme and to 0~~ and the rate constant, which was 2.3 X lo9 M-' s-l at pH 7.0 and ZO-25”, was not much affected by pH, in the range 4.8 + 9.5. Boiling the enzyme or reversibly removing its copper prosthetic group caused loss of catalytic activity. EDTA had no ef...

Saturation behavior of superoxide dismutation catalyzed by the iron containing superoxide dismutase of E. coli B.

The iron containing superoxide dismutase from E. coli B is shown to catalyze superoxide dismutation by a mechanism which exhibits saturation kinetics. This behavior is quite different from that observed previously with bovine Zn/Cuand iron-containing superoxide dismutase from P. leiosnathi. Two parameters of catalysis were measured in the pH range 7.2 to 10.4: k was found to be independent of p...

study of cohesive devices in the textbook of english for the students of apsychology by rastegarpour

this study investigates the cohesive devices used in the textbook of english for the students of psychology. the research questions and hypotheses in the present study are based on what frequency and distribution of grammatical and lexical cohesive devices are. then, to answer the questions all grammatical and lexical cohesive devices in reading comprehension passages from 6 units of 21units th...

Action of Bovine Superoxide Dismutase

Superoxide dismutase Superoxide dismutase