Sporosarcina pasteurii can form nanoscale crystals on cell surface

Using a semi-solid 0.5% agar column, we study the phenomenon of microbially induced mineral (calcium carbonate) by the bacteria Sporosarcina pasteurii. Our platform allows for in-situ visualization of the phenomena, and we found clear evidence of bacterial cell surface facilitating formation of nanoscale crystals. Moreover, in the bulk agar we found the presence of microspheres, which seem to arise from an aggregation of nanoscale crystals with needle like morphology. Extensive chemical characterization confirmed that the crystals to be calcium carbonate, and two different polymorphs (calcite and vaterite) were identified.