The domain within your query sequence starts at position 4 and ends at position 185; the E-value for the DHFR_1 domain shown below is 3.9e-37.



PFAM accession number:PF00186
Interpro abstract (IPR001796):

Dihydrofolate reductase (DHFR) ( EC ) catalyses the NADPH-dependent reduction of dihydrofolate to tetrahydrofolate, which can be used in de novo synthesis both certain amino acids, purines and deoxythymidine phosphate (the precursors of DNA synthesis) [ (PUBMED:2830673) ], and important also in the conversion of deoxyuridine monophosphate to deoxythymidine monophosphate. Although DHFR is found ubiquitously in prokaryotes and eukaryotes, and is found in all dividing cells, maintaining levels of fully reduced folate coenzymes, the catabolic steps are still not well understood [ (PUBMED:3383852) ].

Bacterial species possesses distinct DHFR enzymes (based on their pattern of binding diaminoheterocyclic molecules), but mammalian DHFRs are highly similar [ (PUBMED:500653) ]. The active site is situated in the N-terminal half of the sequence, which includes a conserved Pro-Trp dipeptide; the tryptophan has been shown [ (PUBMED:6815178) ] to be involved in the binding of substrate by the enzyme. Its central role in DNA precursor synthesis, coupled with its inhibition by antagonists such as trimethoprim and methotrexate, which are used as anti-bacterial or anti-cancer agents, has made DHFR a target of anticancer chemotherapy. However, resistance has developed against some drugs, as a result of changes in DHFR itself [ (PUBMED:2601715) ].

GO process:oxidation-reduction process (GO:0055114), tetrahydrofolate biosynthetic process (GO:0046654)
GO function:dihydrofolate reductase activity (GO:0004146)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry DHFR_1