BBB Seminar: Arturo Muga
ClpB, a disaggregase machine
Biophysics Unit and Department of Biochemistry and Molecular Biology, University of the Basque Country, Bilbao, Spain
ClpB is a hexameric chaperone that solubilizes and reactivates protein aggregates in collaboration with the DnaK system. Each of the identical protein monomers contains two nucleotide binding domains (NBDs), whose ATPase activity must be coupled to exert on the substrate the mechanical work required for its reactivation. However, how communication between these sites occurs is at present poorly understood. We are studying the affinity of each of the NBDs for nucleotides in wt ClpB and protein variants in which one or both sites are mutated to selectively impair nucleotide binding or hydrolysis. Our data show that the affinities of the NBDs for nucleotides are different and that the affinity of the NBD1 depends on the nucleotide status of the NBD2. Filling of this NBD with ATP also allows the cooperative binding of substrates to the NBD1 ring. I will also discuss recent findings on the use of ClpB inhibitors as potential bactericide reagents.
Host: Aurora Martinez, Department of Biomedicine