Gallionellaceae

Gallionellaceae is a family of bacteria belonging to the class Betaproteobacteria. These microorganisms are commonly found in freshwater and marine environments, particularly in areas rich in iron. A defining characteristic of Gallionellaceae is their ability to precipitate iron, a process known as iron oxidation. This metabolic capability often results in the formation of reddish-brown deposits around the bacteria, which can accumulate to form significant structures like iron mats.

Members of this family are typically rod-shaped or spiral and possess flagella for motility. They are chemoautotrophic, meaning they derive energy from chemical reactions and synthesize their own organic compounds. The oxidation of ferrous iron (Fe2+) to ferric iron (Fe3+) serves as their primary energy source. This process is crucial in the biogeochemical cycling of iron in aquatic ecosystems.

While the family was historically considered to contain only a few genera, recent phylogenetic studies based on ribosomal RNA gene sequences have expanded its taxonomic diversity. However, the classification and evolutionary relationships within Gallionellaceae are still areas of ongoing research. Their role in iron cycling and their unique morphology make them of interest to microbiologists studying environmental processes and microbial evolution.