[Formation and reactions of biogenic manganese oxides with heavy metals in environment]

Manganese (Mn) oxides are common minerals in natural environments that may play an important role in the biogeochemical cycles of heavy metals. Increasing evidences have shown that Mn (II) oxidation is a microbially-mediated process, and the Mn oxidizing microorganisms are thus recognized as the major drivers of the global Mn cycle. The major pathway for bacterial Mn (II) oxidation is catalysed by a multicopper oxidizing enzyme family. The primary Mn (IV) biooxides are phyllomanganate-like minerals most similar to delta-MnO2 or acid birnessite. Manganese oxides are known to have high sorption capacities for a wide variety of metal ions and considered to be the important environmental oxidant to many metal ions. This paper reviewed the mechanisms of biogenic manganese oxides formation and their reactions with heavy metal ions in environment.