Miroslav Radman

His so-called SOS repair yields exposure of single-stranded DNA, due, for example, to faulty replication or exposure to ionizing radiation or ultraviolet light. A cascade of ensuing events causes replacement of normal DNA replication machinery by an error-prone replication system that sacrifices accuracy for the ability to synthesize DNA across damages, thereby preserving the life of the cell. Methyl-directed mismatch repair, codiscovered with Matthew Meselson, occurs when a base in the growing DNA chain does not form a Watson-Crick pair with the base on the template chain, removing a portion of the abnormal chain and allowing resynthesis to incorporate the correct base. Demonstrated the effect of DNA sequence divergence as a genetic barrier limiting or preventing exchange of DNA between related species of bacteria. Most recently, discovered that the extreme resistance of Deinococcus radiodurans to ionizing radiation does not reflect resistance to DNA damage but correlates with a high degree of protection of protein against radiation-induced oxidation.