Understanding metal-dissolving enzymes.

The availability of metals such as iron and manganese in the soil is essential for life, but these metals are often trapped in insoluble and inaccessible minerals. To release them microorganisms use them to respire in place of oxygen, however this requires a reaction to occur outside the cell surface. In Geobacter sulfurreducens a dedicated mineral reductase called PgcA is responsible for directly catalysing the reduction of iron oxides, but the process is not understood. This project aims to characterise the properties of this enzyme and understand how biological organisms are able to interact and alter insoluble minerals. The techniques involved include small angle X-ray scattering (SAXS) and michalis-menten kinetics adapted to analyse insoluble substrates.