Study Of The Oxidative Stress Resistant Mechanism Of Mold

As an important industrially and medically strain,filamentous fungi can attact human body by resist the oxidative stress from the respiratory burst.The oxidative stress can also reduce the production in the mold fermentation.So if we can understand its oxidative stress resistant mechanism,it will provide a theoretical guidance of new drugs development for the mold,and it will also provide solutions for Production problems caused by the imbalance of oxidative stress in industrial fermentation.However,the study of the oxidative stress resistant mechanism of mold is limited.So,in this work the mechanism of oxidation resistance of mold is studied,the basic results can be summarized as the following:1.We found out that An8692 is the key gene to mould antioxidant.By knocking out the 6 Prx genes of mold,we discovered that the strains knocking out An8692 is extremely sensitive to hydrogen peroxide,and the reverse mutation strains resumed its oxidation resistance.therefore,it is concluded that the key gene for antioxidant is An8692 and we also found out that the cellular localization of the protein encoded by this gene is cytoplasm.2.Enzymology properties analysis indicates that the Prx mold is a special kind of Prx.First,determine the active site by Prx mutation concluded that the mold Prx belongs to a typical 2-cys Prx with CpCR reversed,and it shows a synergy way to combine with the substrates.In addition,we also found that the enzyme is extreme resistance to hydrogen peroxide,whereas sensitive to t-BOOH.3.We clarified the mechanism of the mold Prx extreme tolerance to hydrogen peroxide.By comparing with yeast Ahp 1,we found that mold Prx extreme tolerance to hydrogen peroxide attribute to the TrxR of mold.So this results broke the idea of that the tolerance of Prx system is decided by the Prx tolerance.4.We established a new method for detection of hydrogen peroxide Based on the measurement of the consumption of NADPH when Prx reacting with hydrogen peroxide,we established a simple,rapid,accurate,and strong anti-interference method of hydrogen peroxide detection.