The researchers have used a combination of magnetic tweezers and total internal reflection fluorescence (TIRF) microscopy, a technology pioneer in Spain, to study interactions between DNA and proteins. Using these approaches, they have observed that an excess of free C-terminal Domain (CTD) of ParB protein impeded DNA condensation or even promoted decondensation of pre-assembled networks.
"In the specific case of ParB, there is still a lack of connection between the models proposed by our experiments and how the DNA organisation is carried out in vivo in Bacillus subtilis”. The experiments carried out help to understand the segregation mechanisms of bacterial chromosomes and to reveal the pieces of this complex biological puzzle, "explains CNB researcher Julene Madariaga.
Julene Madariaga-Marcos, Cesar L. Pastrana, Gemma L. M. Fisher, Mark S. Dillingham and Fernando Moreno-Herrero. ParB dynamics and the critical role of the CTD in DNA condensation unveiled by combined force-fluorescence measurements. eLife. 2019;8:e43812