| Title | Heat Shock Causes Oxidative Stress and Induces a Variety of Cell Rescue Proteins in Saccharomyces cerevisiae KNU5377 |
|---|---|
| Author | Il-Sup Kim1, Hye-Youn Moon2, Hae-Sun Yun3, and Ingnyol Jin*1 |
| Address | 1Department of Microbiology, Kyungpook National University, Daegu 702-701, Republic of Korea, 2Metabolic Engineering Laboratory, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-600, Republic of Korea, 3Division of Enteric and Hepatitis Viruses, Center for Infectious Diseases, National Institute of Health, Seoul 122-701, Republic of Korea |
| Bibliography | Journal of Microbiology, 44(5),492-501, 2006, |
| DOI | |
| Key Words | Saccharomyces cerevisiae KNU5377, heat shock, oxidative stress, antioxidant enzymes, heat shock proteins, trehalose, fatty acid composition |
| Abstract | In this study, we attempted to characterize the physiological response to oxidative stress by heat shock in Saccharomyces cerevisiae KNU5377 (KNU5377) that ferments at a temperature of 40°C. The KNU5377 strain evidenced a very similar growth rate at 40°C as was recorded under normal conditions. Unlike the laboratory strains of S. cerevisiae, the cell viability of KNU5377 was affected slightly under 2 hours of heat stress conditions at 43°C. KNU5377 evidenced a time-dependent increase in hydroperoxide levels, carbonyl contents, and malondialdehyde (MDA), which increased in the expression of a variety of cell rescue proteins containing Hsp104p, Ssap, Hsp30p, Sod1p, catalase, glutathione reductase, G6PDH, thioredoxin, thioredoxin peroxidase (Tsa1p), Adhp, Aldp, trehalose and glycogen at high temperature. Pma1/2p, Hsp90p and H+-ATPase expression levels were reduced as the result of exposure to heat shock. With regard to cellular fatty acid composition, levels of unsaturated fatty acids (USFAs) were increased significantly at high temperatures (43°C), and this was particularly true of oleic acid (C18:1). The results of this study indicated that oxidative stress as the result of heat shock may induce a more profound stimulation of trehalose, antioxidant enzymes, and heat shock proteins, as well as an increase in the USFAs ratios. This might contribute to cellular protective functions for the maintenance of cellular homeostasis, and may also contribute to membrane fluidity. |
| Download PDF | JM 44(5)-03.pdf |