dihidrofolátreduktáz

Dihidrofolát reduktáz, often abbreviated as DHFR, is a crucial enzyme found in a wide variety of organisms, including bacteria, protozoa, plants, and animals. Its primary function is to catalyze the reduction of dihydrofolate to tetrahydrofolate. This reaction is a vital step in the folate metabolic pathway, which is essential for the synthesis of purines and pyrimidines, the building blocks of DNA and RNA. Tetrahydrofolate also serves as a cofactor in the metabolism of certain amino acids.

The enzyme's activity is critical for cellular growth and proliferation. Because of its essential role in DNA synthesis, DHFR is a common target for antimicrobial and anticancer drugs. For example, methotrexate is a well-known chemotherapy drug that inhibits human DHFR, thereby disrupting cancer cell growth. Similarly, trimethoprim is an antibiotic that selectively inhibits bacterial DHFR, interfering with bacterial replication. The differences in the structure of DHFR between humans and bacteria allow for selective inhibition by these drugs. This selectivity is key to their therapeutic effectiveness while minimizing harm to host cells.