Affiliation:
1. Department of General and Industrial Microbiology, Faculty of Biology, The Sofia University, St. Kliment Ohridski, Sofia, Bulgaria.
Abstract
The enzymatic defence system in the 2 yeasts Kluyveromyces marxianus and Rhodotorula glutinis , differing in their mode of oxygen uptake and energy generation, was characterized and compared with the well-studied facultatively fermentative Crabtree-positive Saccharomyces cerevisiae strain. Twofold higher superoxide dismutase (SOD) and catalase activities were detected in K. marxianus and R. glutinis when cells were cultured on glucose. Further increases of 10%–15% in SOD activity and 30%–50% in catalase were measured in all studied yeasts strains after transfer to media containing ethanol. An evaluation of the ratio of Cu/Zn SOD / Mn SOD was performed as a measure of the oxidative metabolism. A 20% decrease was observed when the respiratory source of energy was ethanol, with the lowest ratio being observed for the oxidative type of K. marxianus yeasts. Electrophoretic analysis revealed that all tested strains possess active Cu/Zn and Mn SODs. A reverse electrophoretic mobility pattern of K. marxianus and R. glutinis SOD enzymes was observed in comparison with the same couple in S. cerevisiae. The investigation of electrophoretic profile of catalase enzymes showed that alongside their different taxonomic status and fermentative capacity, all tested strains possess 2 separate catalases. The role of antioxidant enzymes in preventing oxidant-induced cytotoxicity (treatment with hydrogen peroxide, paraquat, and menadione) was shown.
Publisher
Canadian Science Publishing
Subject
Genetics,Molecular Biology,Applied Microbiology and Biotechnology,General Medicine,Immunology,Microbiology
Reference31 articles.
1. Aebi, H. 1981. Catalase. Methods of enzymatic analysis.InMethods for determination of enzyme activity. Vol. 2.Edited byH.U. Bergmeyer and K. Gawehn. Verlag Chemie Int., Deerfield Beach, Florida. pp. 673–684.
2. Superoxide dismutase: Improved assays and an assay applicable to acrylamide gels
3. Bull, A.T., and Bushell, M.E. 1976. Environmental control of fungal growth.InThe filamentous fungi. Vol. 2.Edited byJ.E. Smith and D.R. Berry. J. Wiley, New York. pp. 1–33.
4. Genetic basis of toxic reactions to drugs and chemicals
5. Protective role of mitochondrial superoxide dismutase against high osmolarity, heat and metalloid stress inSaccharomyces cerevisiae
Cited by
18 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献