Spectroscopic analysis of polymerization and exonuclease proofreading by a high-fidelity DNA polymerase during translesion DNA synthesis

► Non-natural nucleotide that monitors incorporation and excision via fluorescence ► A nucleotide that probes the mechanism of normal versus translesion DNA synthesis ► Identification of a pre-excision complex formed with different DNA lesions ► Exonuclease proofreading is in direct competition with polymerase translocation.