Structure and Dynamics of the water-amorphous
silica interface
Ali Hassanali
Homologous Recombination: Insights into cation induced
functionality of human RAD51
Ravindra Amunugama
Human RAD51 (HsRAD51) is an essential component in the homologous recombinational repair pathway. Unlike its robust bacterial homologue RecA, HsRAD51 requires specific cations for efficient in vitro recombinase activity. Recent structural analyses of the Archaebacterial RAD51 homologue have shown rearrangements of several amino acid residues at the subunit interfaces of the presynaptic nucleoprotein filament, when potassium ions were introduced. We have identified the homologous residues of HsRAD51 and constructed site-directed mutants F129V and H294V. These recombinant proteins were expressed and purified to near homogeneity. Initial biochemical studies of DNA binding, ATP hydrolysis and strand exchange activity signify an intricate mechanism at the active site that reflects the cation dependence of HsRAD51.