Effect of Proteinogenic and Non-proteinogenic Amino Acids of the Native Protease Activity of Forest Soils

Abstract

Soil proteolytic complex plays an important role in nutrient cycling in the ecosystem. Interactions of this enzyme complex with proteinogenic and non-proteinogenic amino acids were studied on the cambisol (stands of beech, oak and spruce) and Rendzic Leptosol (beech stand) soil types. The aim of the study was to find out how does native soil protease react for the presence of amino acids, i.e., substances which are released during the decomposition of organic matter, get into the soil and the environment and represent important sources of nitrogen and carbon. The overall activity of the native soil protease was stimulated by the proteinogenic and non-proteinogenic amino acids. In three cases there was an inhibition. In one case, an inhibitory effect of the protease on proteinogenic amino acids (ᴅ-glutamic acid) was observed in an organic horizon of a spruce stand and, in two cases, on non-proteinogenic amino acids (ʟ-ornithine and ʟ-citrulline) in an organomineral horizon of a spruce stand.