Recombinant E.coli uvrD protein

The uvrD gene product, a member of the SF1 superfamily of ATP-dependent helicases, is a conserved bacterial protein critical for maintaining genomic stability. Originally identified in *Escherichia coli*, UvrD (also called Helicase II) functions as a molecular motor that unwinds double-stranded DNA in a 3'→5' direction using ATP hydrolysis. It plays multifaceted roles in DNA repair pathways, including nucleotide excision repair (NER) where it collaborates with the UvrABC endonuclease complex to remove bulky DNA lesions. Additionally, UvrD participates in mismatch repair (MMR) by displacing error-containing DNA strands and in recombinational repair by dismantling RecA filaments to prevent aberrant recombination. Its ability to reverse stalled replication forks and resolve transcription-replication conflicts further underscores its importance in genome maintenance.

Recombinant UvrD protein is engineered for in vitro studies through heterologous expression systems, typically in *E. coli*, followed by affinity purification (e.g., His-tag chromatography). This purified protein serves as a model system to dissect helicase mechanics, substrate specificity, and coordination with partner proteins like MutS/L or RecA. Structural studies using recombinant UvrD have revealed domain organization and conformational changes during ATP-driven unwinding. Beyond fundamental enzymology, UvrD is explored as a potential antimicrobial target due to its essentiality in some pathogens and its role in antibiotic resistance mechanisms. Recent work also examines its synthetic lethality with other DNA repair defects, offering insights for combinational therapeutic strategies. The protein's biochemical versatility continues to make it a key subject in understanding DNA transaction processes and bacterial stress responses.