Soil heterotrophic bacteria in transformations of inorganic sulphur

Abstract

The occurrence of biochemical activities of the sulphur cycle was followed in isolates of heterotrophic bacteria from the fermentative horizon of a spruce stand, a grass-covered withered spruce stand and of mountain ash and birch stand in the area strongly influenced by sulphur immissions. The occurrence of bacteria capable of reducing S0 to S2−, oxidizing S0 and S2O3 2− to SO4 2− and solubilizing S0 increased in the above order. The occurrence of producers of thiosulphate sulphurtransferase (rhodanese), thiosulphate oxidase and sulphite oxidase increased and the level of the production of these enzymes increased as well. Heterotrophic bacteria (mostly pseudomonads) from the grass-covered stands exhibit more activities of the sulphur cycle than bacteria from the spruce stand without ground vegetation.