ИСТИНА

One of the strategies implemented in bacterial cells is related to the protection of the nucleoid from unfavourable environmental conditions by binding of DNA to specific histone­like proteins, the main one being the protein Dps (DNA binding protein from starved cells), and condensation of DNA with DPS in nanocrystalline complex which was recently discovered in gram­negative bacteria. A series of diffraction experiments to study structural response to stress or stress­induced biocrystallization in bacteria E. coli, spore ­forming bacteria Bacillus cereus, in cells and spores of mycelial fungus Umbelopsis ramanniana was performed for the first time. Zones of increased intensity at resolution 90 Å and 44 Å indicate an ordered organization (most likely nanocrystalline) of bacterial nucleoid in E.coli cells. For the starving bacteria Bacillus cereus peak at a resolution of 45 Å, apparently, also associated with the presence of nanocrystalline complexes of DNA with histone­like proteins. The spores of the fungus Umbelopsis ramanniana BKM F­582, as well as the spores of Bacillus cereus create ordered sets of DNA molecules with DNA condensing acid ­ soluble proteins SASPs. Starving, dehydrated mycelial cells of the fungus Umbelopsis ramanniana, form ordered structures at resolutions of 27 Å to 55Å.The series of peaks reflects the formation of a number of orderly protein formations with continuously changing characteristic size of the interplanar spacings.