EN
The purpose of the study was to estimate the influence of temperature increase on Hsp70 induction in M. haemolytica serovar 1 strains. Three wildtype M. haemolytica strains, obtained from calves respiratory tracts and incubated at a temp of 41.5°C for 2 hours were used as the research material. Analyses of particular fractions were carried out by SDS-PAGE electrophoresis and identification of obtained proteins by immunoblotting (Western blotting) using polyclonal rabbit anti Hsp70 antibodies. The first step was to separate the capillaries in gradient pH 5/7 and 3/10 which was carried out in two-dimensional electrophoresis. The second step was carried out in SDS-PAGE electrophoresis using 4% stocking and 12% resolving gels. An analysis of SDS-PAGE electrophoresis revealed additional protein fractions, displaying positive reactions with anti-Hsp70 antibodies. The presence of these proteins was observed both in membrane and cytoplasmatic bacterial cell fractions. The molecular weight of the obtained proteins ranged between 77.5-79 kDa. The additional protein fractions were present in membrane fractions between molecules, weighed 22-26 kDa, as well as displaying a positive reaction with anti-Hsp70 antibodies. The electrophoregrams obtained in 2D electrophoresis revealed the presence of additional spots in membrane, cyto- and periplasmatic fractions. The obtained results suggest the potential for M. haemolytica strains to produce Hsp70 during stress induced by temperature increase.