Urease Activity of Ureolytic Bacteria Isolated from Six Soils in which Calcite was Precipitated by Indigenous Bacteria

Ten distinct and phylogenetically diverse bacterial strains able to produce urease constitutively, even in the presence of high levels of ammonia, were isolated. Each isolate was characterized with respect to morphology, growth conditions, 16S rRNA sequence identity and the urease specific activity each isolate was measured. At least one bacteria that was able to hydrolyze urea in the presence of high concentration of ammonia was isolated from each soil tested. These results indicate that constitutive production of urease is a common trait in soil bacteria. This makes the general application of biomineralization process based on stimulation of urea hydrolysis possible and potentially useful for a variety of soil bioengineering and environmental bioremediation applications.