Bacterially mediated manganese deposition in novel "anelli" within the biofilms of an impacted urban stream

Abstract

The purpose of this work is to identify bacteria responsible for the formation of manganese containing anelli within stream biofilms, and study their distribution. Manganese oxidising bacteria are part of a diverse group of organisms found commonly within many disparate environments, which deposit manganese and iron biominerals within biofilms and flocs [1]. The purpose of microbial manganese oxidation is poorly understood, but may be associated with energy production, mobilisation of nutrients, protection and/or detoxification [1, 2]. Manganese has a high sorptive capacity for heavy metals, metalloids, and other ions, as well as a strong oxidizing potential, and therefore frequently induces co-precipitation of cations present within the surrounding environment [1]. Within urban streams contaminants such as heavy metals may therefore potentially be concentrated within steam biofilms in the presence of manganese oxidising bacteria.