Engineered Template-Dependent DNA Polymerases with an Expanded Substrate Scope

DNA polymerases are valuable biotechnological tools with applications ranging from DNA sequencing to synthesis. Many of these uses require polymerases with high efficiency toward nucleoside triphosphate analogues featuring chemical modifications, such as fluorophores for imaging, reactive handles for downstream conjugation, or functional groups that improve the metabolic stability of therapeutics. Although natural polymerases often display limited efficiency toward these important modifications, enzyme engineering has delivered improved variants with an expanded substrate scope. In this review, we highlight recent developments in polymerase engineering that are enabling advances in biotechnology and medicine.