Catalase
As a microbiologist we know some aerobic microorganisms produce catalase and we test it by adding hydrogen peroxide to the culture.
what do the catalase do in a microbial cell?
Hydrogen peoxide is produced in microbial cell during the exposure to Oxygen. The enzyme catalase breaks down hydrogen peroxide to water and oxygen.
2 H2O2 → 2 H2O + O2
Even anaerobic organisms like Methanosarcina barkeri produce catalase under oxidative stress.
In all animal cells and plant cells catalase is ubiquitously present. In humans the highest concentration of catalase is observed in Liver. Animals manage to survive even without catalase. Mouse with deleted catalase gene function normally. In humans deficiency of catalase may be linked with type II diabetes.The deficiency of catalase may lead to graying of hair due to the build up of hydrogen peroxide in body.
Some insects like Bombardier beetle uses catalase in another way. It has sac of catalase and sac of hydrogen peroxide and hydroquinones. For defence it squeezes the sacs. reaction of catalase with hydrogen peroxide cases release of oxygen which in turn causes oxidation of hydroquinones. It raises the temperature to boiling point. Vaporization and release of gases lead to the repellent spray and protects the insects from predators.
Image source: https://www.cdc.gov/meningitis/lab-manual/images/chapt8-figure04.gif
what do the catalase do in a microbial cell?
Hydrogen peoxide is produced in microbial cell during the exposure to Oxygen. The enzyme catalase breaks down hydrogen peroxide to water and oxygen.
2 H2O2 → 2 H2O + O2
Even anaerobic organisms like Methanosarcina barkeri produce catalase under oxidative stress.
In all animal cells and plant cells catalase is ubiquitously present. In humans the highest concentration of catalase is observed in Liver. Animals manage to survive even without catalase. Mouse with deleted catalase gene function normally. In humans deficiency of catalase may be linked with type II diabetes.The deficiency of catalase may lead to graying of hair due to the build up of hydrogen peroxide in body.
Some insects like Bombardier beetle uses catalase in another way. It has sac of catalase and sac of hydrogen peroxide and hydroquinones. For defence it squeezes the sacs. reaction of catalase with hydrogen peroxide cases release of oxygen which in turn causes oxidation of hydroquinones. It raises the temperature to boiling point. Vaporization and release of gases lead to the repellent spray and protects the insects from predators.
Comments
Post a Comment