MANGANESE-CONTAINING CATALASE FROM THERMUS-THERMOPHILUS PEROXIDE-INDUCED REDOX TRANSFORMATION OF MANGANESE IONS IN PRESENCE OF SPECIFIC INHIBITORS OF CATALASE ACTIVITY

The mechanism of peroxide decomposition involves: interconvertion of two equally active redox states: (Mn2+, Mn2+) and (Mn3+, Mn3+) states. Various inorganic anions such as Cl- or HPO-4 inhibit catalase activity by binding to the (Mn2+, Mn2+). This inhibition can also be observed following reduction of the (Mn3+, Mn3+) states to (Mn2+, Mn2+) by peroxide. The (Mn3+, Mn4+) state, which can be formed by periodate oxidation, does not interact with these anions and is inactive in peroxide decomposition. The (Mn2+, Mn3+) state, which forms in a minority of centers by auto-oxidation, also appears not to participate in a major way in peroxide decomposition. © 1990.