Oligomerization of the IHF Protein in the Presence of Metal Cations

The oligomeric state of the nucleoid-associated protein IHF (integration host factor) plays a significant role in the organization and compaction of the bacterial nucleoid and also in the evolution of bacterial resistance to unfavorable environmental conditions, in particular to antibiotics. Although IHF was identified more than 25 years ago, the molecular mechanisms of its participation in these processes are poorly understood. Using small-angle X-ray scattering, it was demonstrated for the first time that there are different oligomeric states of IHF in an aqueous medium depending on the presence of metal cations. It was found that the presence of Mg²⁺ and K⁺ ions hinders the formation of high-order oligomers of IHF. The results of this study may be useful in the development of strategies against bacterial resistance to drugs.