Dual role of plasma membrane electron transport systems in defense

Because oxidative stress is one of the main sources of severe cellular dama ge, cells have different defense weapons against reactive oxygen species. U biquitous plasma membrane redox systems play a role in defense against oxid ative stress damage. On the other hand, a tightly controlled and localized production of reactive oxygen species by a plasma membrane NADPH oxidase ca n be used as a potent microbicidal weapon. This dual, prooxidant and antiox idant role of plasma membrane electron transport systems in defense is stud ied and discussed.