ABSTRACT
Bacteria isolated from the black crusts of the Diputacion Foral de Gipuzkoa were tested for their ability to use a number of carbon sources. Low molecular weight compounds related with partially combusted or uncombusted fossil fuels were readily used as carbon source. Anthropogenic activities, particularly the burning of fossil fuels, are significant sources of organic pollutants released into the environment via atmospheric deposition. Polycyclic aromatic hydrocarbon-degrading bacteria have been used as indicators of the microbial activity in polluted environments. T. Warscheid et al. studied chemoorganotro-phic bacteria from the uppermost layers of sandstones of German monuments. It was shown that most of the isolated bacteria used a wide range of different carbohydrates, amino acids, fatty acids, and hydrocarbons. Bacteria are able to remove some of the most abundant components of black crusts, such as aliphatic hydrocarbons, aliphatic carboxylic acids, and polycyclic aromatic hydrocarbons. This indicates that nature develops strategies for biodegradation of pollutants in urban environments.
