Design of a Comprehensive Experiment on Competitive Inhibition in Succinate Dehydrogenase

To enhance students’ biochemical experimental operation and analysis skills, a comprehensive design and exploration is conducted on the competitive inhibition of succinate dehydrogenase. This involves improving the enzyme extraction method, optimizing the reaction system, determining the enzymatic reaction conditions, and adding experimental controls. The result show that using muscle homogenate obtained by grinding muscle and removing red blood cells as the improved crude enzyme extract eliminated color interference make the phenomenon of competitive inhibition more apparent. The ratio of crude enzyme extract, succinic acid and methylene blue is fixed in the enzymatic reaction system. The reaction is carried out at pH 7.4 and 37℃ for 15 min, with the addition of a succinate-free control. This results in good experimental repeatability. The comprehensive design of the experiment is beneficial for students to understand the principles and characteristics of competitive inhibition of enzymes, as well as the factors that affect enzyme activity.