DEALING WITH ACTIVE OXYGEN INTERMEDIATES - A HALOPHILIC PERSPECTIVE

Although oxygen tensions in the halophilic environment are diminished, they are nevertheless sufficient for the generation of active oxygen intermediates as byproducts of metabolism. Therefore, like all other a erobes, halophilic bacteria are compelled to possess the means to deto xify potentially lethal active oxygen intermediates. This review exami nes the superoxide, hydrogen peroxide, hydroxyl radical and singlet ox ygen scavenging capacity of the halophiles, Halobacterium spp. Specifi cally, it looks at the potential of the bacteria to generate active ox ygen intermediates and then examines the roles of superoxide dismutase , catalase, peroxidase and catalase-peroxidase. It also looks at some non-enzymatic means of neutralizing potentially lethal active oxygen i ntermediates.