Through secretion of organic acids (above all a-Oxoglutar, and citric acid, but also Isocitronen, and cis-Aconitsäure) and other metabolites, molds can evoke corrosion-tracks on the surface of aluminium, copper, iron and lead. ,  can considerable degrees of iron tubes damages through bacterias and other appliances assumes. These are evoked by iron and sulfur-bacterias, that is corrosions, constipations of the directions through cell-bulks of Sphaerotilus, Denitrifikanten, Desulfurikanten Pseudomonaden unda.  as well becomes some bacterias industrially copper for ore-reappraisal, for example, Manganese and others started.  a problem represents heavy metal-loaded grounds. Until now, the contaminated base-work periods had to be removed extensively. Base-bacterias, who show a resistance opposite nickel, cadmium, chrome or copper, are a more cost-advantageous alternative. Several trunks, that pick up the named heavy metals from the base and can store in her/its/their cells, were found. The heavy metals are bound in the microorganisms with it and can reach no more into fluxions and groundwater with the Sickerwasser or by plants are picked up.