Chuiko N. The chemotactic properties of Bradyrhizobium japonicum

The dissertation is devoted to research of chemotactic properties of the slowgrowing nodule soy bacteria. The dependence of Bradyrhizobium japonicum chemotaxis from bacteria population density, growth phase of culture, pH, temperature of an environment is investigated. Chemotaxis of B. japonicum strains with various nitrogen-fixing activity to a number aminoasids, carbohydrates, organic acids, and also to soy seeds extracts that different of symbiotic sensitivity to nodule bacteria is researched. The negative influence on B. japonicum chemotaxis to glucose of natural highly dispersed materials (montmorillonite and palygorskite clay minerals) which are components of many soil types, and synthetic highly dispersed materials (silicon dioxide (HSD) and modified aluminium oxide silicon dioxide (MHSD)) is shown. The decrease of a level of chemotactic response is connected with sorption of dispersed particles on a surface of bacteria, and, as a consequence, blocking of chemotactic receptor proteins and decreasing sensitivity B. japonicum to attractant. The positive action of montmorillonite, palygorskite, HSD and negative - MHSD on nodule soy bacteria motility is revealed. This correlates with influence these highly dispersed materials on growth B. japonicum. A related nature of mechanisms of these dependencies is supposed.