Superoxide dismutase and catalase in Azotobacter vinelandii grown in continuous culture at different dissolved oxygen concentrations |
| |
Authors: | Ch Dingler J Oelze |
| |
Institution: | (1) Institut für Biologie II (Mikrobiologie), Universität Freburg, Schänzlestr. 1, D-7800 Freiburg, Federal Republic of Germany |
| |
Abstract: | Superoxide dismutase and catalase activities were studied in Azotobacter vinelandii grown diazotrophically at different ambient oxygen concentrations in continuous culture. Activities were expressed either as specific activity or activity per cell. Specific superoxide dismutase activity increased by a factor of 1.6 with increasing oxygen concentration from about 1% to 90% air saturation of the growth medium whereas specific catalase activity increased only slightly, if at all. Since cell volumes increased in parallel to increases in the oxygen concentration cellular superoxide dismutase activities increased by a factor of 4.3 while cellular catalase activities increased by a factor of 3.3. Under all conditions only the Fe-containing form of superoxide dismutase was detected. The possible function of these enzymes in the protection nitrogenase from oxygen damage is discussed.Abbreviation SOD
superoxide dismutase |
| |
Keywords: | Azotobacter vinelandii Superoxide dismutase Catalase Continuous culture |
本文献已被 SpringerLink 等数据库收录! |