Resistance of various soil geosystem bacteria to enzymatic lysis at different pH

Abstract

Bacteria appear to be an inevitable element of soil geochemistry because they participate actively in chemical transformations of soil media components. One of the factors determining the composition of bacterial population in soil is resistance of bacteria to enzymes which hydrolyze cell walls. In the following research, resistance of bacteria (Priestia megaterium, Micrococcus luteus and Escherichia coli) to lysozyme in the pH range appropriate for soils is investigated. All the three species are proved to be most sensitive to lysozyme in slightly alkaline conditions (P. megaterium is least resistant at pH 8.0, M. luteus at pH 8.3, E. coli at pH 8.5), and resistance of all the three microorganisms in the range of pH values of 6.0—7.0 changes insignificantly. A possible factor defining the pH optimum for lysozyme activity in relation to these bacteria is the structure of negatively charged components of their cell walls and outer membranes.