Constructive bacteria

2003/06/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Materialak

Limestone buildings deteriorate little by little due to weather conditions and pollutants. Now, minerologists from the University of Granada have discovered a suitable bacterium that can protect the stone and must undergo tests in the Alhambra.

The limestone is very sensitive to the action of the medium, since it is very porous and therefore has a large surface of contact with substances from the outside. Therefore, buildings with such stones deteriorate faster than others. To address this problem, scientists have proposed adding bacteria that produce calcium carbonate (calcite), but the results have not been satisfactory; the carbonate that generates only cover the pore of the rock and hinders the exit of moisture.

The calcite that forms Myxococcus xanthus is well adhered to pebbles. According to the mineralogical of Granada, the bacteria follow the same orientation as the original stone. This bacterium allows to recover the buildings, so scientists will test this methodology in the Alhambra.