|Jmol 3D model||Interactive image|
|Molar mass||445.43 g/mol|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Tetrahydrofolic acid, or tetrahydrofolate, is a folic acid derivative.
Many bacteria use dihydropteroate synthetase to produce dihydropteroate, a molecule without function in humans. This makes it a useful target for sulfonamide antibiotics, which compete with the PABA precursor.
It is a cofactor in many reactions, especially in the metabolism of amino acids and nucleic acids. It acts as a donor of a group with one carbon atom. It gets this carbon atom by sequestering formaldehyde produced in other processes. A shortage in tetrahydrofolic acid (FH4) can cause megaloblastic anemia.
Methotrexate acts on dihydrofolate reductase, like pyrimethamine or trimethoprim, as an inhibitor and thus reduces the amount of tetrahydrofolate made. This may result in megaloblastic anemia.
Tetrahydrofolic acid is involved in the conversion of formiminoglutamic acid to glutamic acid; this may reduce the amount of histidine available for decarboxylation and protein synthesis, and hence the urinary histamine and formiminoglutamic acid may be decreased.
- Rajagopalan, P. T. Ravi; Zhang, Zhiquan; McCourt, Lynn; Dwyer, Mary; Benkovic, Stephen J.; Hammes, Gordon G. (2002-10-15). "Interaction of dihydrofolate reductase with methotrexate: Ensemble and single-molecule kinetics". Proceedings of the National Academy of Sciences. 99 (21): 13481–13486. doi:10.1073/pnas.172501499. ISSN 0027-8424. PMC . PMID 12359872.
- Dawson W, Maudsley DV, West GB (December 1965). "Histamine formation in guinea-pigs". J. Physiol. (Lond.). 181 (4): 801–9. doi:10.1113/jphysiol.1965.sp007798. PMC . PMID 5881255.