EC Number   |
General Information |
Reference |
|---|
    2.7.7.2 | evolution |
eukaryotic FMNAT is related to phosphoadenosine phosphosulfate (PAPS) reductase family proteins and contains a core domain with a modified Rossman-fold topology and a C-terminal extension |
737678 |
| 2.7.7.2 | evolution |
whereas the N-terminal module of FADS lacks structural homology to eukaryotic FMNATs, the kinase module is homologous to monofunctional RFKs |
737357 |
| 2.7.7.2 | metabolism |
the enzyme catalyzes the last step in the metabolic pathway producing FAD, redox cofactor ensuring the activity of many flavoenzymes mainly located in mitochondria but also relevant for nuclear redox activities |
-, 738594 |
| 2.7.7.2 | more |
molecular dynamics simulations of riboflavin kinase domain bound to FMN, ADP, and Mg2+, structure-function analysis, flavin-binding site structure in the RFK module of CaFADS, overview |
737357 |
| 2.7.7.2 | more |
residue E268 is the catalytic base of the kinase reaction. The salt bridge between E268 at the RFK site and R66 at the FMNAT-module is important for the riboflavinkinase activity. Cross-talk between the RFK- and FMNAT-modules of neighboring protomers in the CaFADS enzyme, and participation of R66 in the modulation of the geometry of the RFK active site during catalysis |
737771 |
| 2.7.7.2 | physiological function |
distortion of aromaticity at the FMNAT isoalloxazine binding cavity prevents FMN and FAD from correct accommodation in their binding cavity and decreases the efficiency of the FMNAT activity. The side-chains of F62, Y106 and F128 are relevant in the formation of the catalytic competent complex during FMNAT catalysis in bifunctional FAD synthase |
761310 |
| 2.7.7.2 | physiological function |
flavocoenzymes, including flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), are versatile redox cofactors involved in many fundamental cellular processes in all living organisms. FAD is synthesized from riboflavin obtained from the diet via two enzymatic steps catalyzed by riboflavin kinase (RFK, EC 2.7.1.26) and essential FMN adenylyltransferase (FMNAT,EC 2.7.7.2). Phosphorylation of riboflavin by RFK is crucial for specific absorption of the vitamin and is the physiologically rate-limiting step in the biosynthesis of flavocoenzymes, whereas product (FAD) feedback inhibition is observed for mammalian FMNAT, suggesting that biosynthesis of FAD is also regulated at the FMNAT reaction step |
737678 |
| 2.7.7.2 | physiological function |
in a truncated FADS variant consisting in the isolated C-terminal ATP:riboflavin kinase RFK module, RFK activity is similar to that of the full-length enzyme. Inhibition of the RFK activity by the RF substrate is independent of the FMN:ATP adenylyltransferase module, and FMN production, in addition to being inhibited by an excess of riboflavin, is also inhibited by both of the reaction products. Mg2+ and the concerted fit of substrates are required to achieve a catalytically competent geometry |
760159 |
| 2.7.7.2 | physiological function |
molecular docking and molecular dynamics simulations with ATP/Mg2+ and FMN in both the monomeric and dimer-of-trimers assemblies. For the dimer-of-trimers conformation, the RFK module negatively influences FMN binding at the interacting FMNAT module. FMN binds to the monomer but not to the dimer-of-trimers. The presence of the RFK module (residues E268, D298, and V300) considerably impairs FMN binding at the FMNAT active site and decreases the FMNAT catalytic efficiency |
760710 |
| 2.7.7.2 | physiological function |
the enzyme catalyzes the last step in the metabolic pathway producing FAD, redox cofactor ensuring the activity of many flavoenzymes mainly located in mitochondria but also relevant for nuclear redox activities |
-, 738594 |
