[Probing the structure of bacterial deoxyribonucleoproteins with exogenous and endogenous nucleases]

During digestion of deoxyribonucleoproteins (DNP) of gram-negative bacteria by micrococcal nuclease and Ca2+, Mg2+-dependent endonuclease in situ regular series fragments-and large nuclease-resistent fragments of DNP were revealed by electrophoresis. The DNP length of the smallest DNP-fragment was tentatively 120-140 base pairs. In investigated bacterial species DNP contained at least two basic proteins which had electrophoretic mobility similar to that of histone H4 of eucaryot. It is suggested that bacterial DNPs have common regular structure.