DHFR Recombinant Rabbit mAb (S-2542-9)

Dihydrofolate reductase (DHFR) is a small, ~21 kDa oxidoreductase that catalyzes the NADPH-dependent reduction of 7,8-dihydrofolate to 5,6,7,8-tetrahydrofolate, thereby regenerating the essential one-carbon carrier required for de novo purine and thymidylate synthesis, making DHFR indispensable for DNA replication and cell proliferation, and its active site, containing a deeply bound nicotinamide and a flexible Met20 loop that alternates between closed and occluded conformations to control cofactor and substrate access, has been exploited for over seven decades by antifolate drugs such as methotrexate, pemetrexed, and trimethoprim that competitively block the folate-binding pocket, with differential binding kinetics and species-specific residue changes underpinning selective toxicity toward rapidly dividing cancer cells, bacteria, and parasites, while human DHFR variants (e.g., A19V, S59G, R28W) can confer resistance to antifolates, and beyond its canonical role DHFR is also implicated in oxidative stress responses, mitochondrial folate metabolism, and as a transcriptional regulator, with post-translational modifications like phosphorylation and nitrosylation modulating its stability and subcellular localization, and its expression levels serving as prognostic markers in leukemia, breast, and lung cancers, thus continuing to position DHFR as a central hub in both basic folate biochemistry and clinically relevant chemotherapy and antimicrobial strategies.