Magnetotactic Bacteria - Magnetosomes

Magnetosomes

The biomineralisation of the magnetite requires regulating mechanisms to control the concentration of iron, the crystal nucleation, the redox potential and the pH. This is achieved by means of compartmentalisation in structures known as magnetosomes that allow the biochemical control of the above mentioned processes. After the genome of several MTB species had been sequenced, a comparative analysis of the proteins involved in the formation of the BMP became possible. Sequence homology with proteins belonging to the ubiquitous cation diffusion facilitator (CDF) family and the "Htr-like" serine proteases has been found: While the first group is exclusively dedicated to the transport of heavy metals, the second group consists of heat shock proteins (HSPs) involved in the degradation of badly folded proteins. Other than the serine protease domain, some proteins found in the magnetosomial membrane (MM) also contain PDZ domains, while several other MM proteins contain tetratrico peptide repeat (TPR) domains.