Flavin mononucleotide (FMN)

**Flavin mononucleotide (FMN)**, also called riboflavin-5'-phosphate, is a derivative of riboflavin (vitamin B2) produced by phosphorylation via the enzyme flavokinase[4][8]. FMN acts as a **redox-active coenzyme** for a wide variety of oxidoreductase enzymes, participating in key electron transfer steps during metabolic processes such as aerobic respiration and photosynthesis[2][4][6][8]. In mitochondria, FMN serves as the first redox cofactor in respiratory Complex I (NADH:ubiquinone oxidoreductase)[8]. FMN is also a cofactor for biological blue-light photoreceptors. It is found bound to proteins as a non-covalent or covalent prosthetic group, contributing to enzymatic catalysis of both one- and two-electron transfer reactions[4][7]. FMN is not a protein target but an essential **cofactor** and **metabolic intermediate**, not considered a direct therapeutic target, receptor, enzyme, or transporter. It is also used as a food color additive (E101a)[4][3]. --- **Explanation of key fields:** - Flavin mononucleotide is not a protein or a receptor—it is a small molecule coenzyme; thus, while essential in biological function, it is not a therapeutic "target" in the conventional sense. Therefore: - **is_target:** false - **is_incorrect:** true (not a legitimate "target" for typical drug action; likely a misinterpretation or miscategorization) - It has many **aliases** related to its chemical structure or food additive use[3][4]. - It functions as a **cofactor** in numerous biological electron transfer reactions, but does not fall within conventional molecular target **families** like receptor, enzyme, or transporter[2][4][6][8]. - It is central to metabolism and energy production but is not itself a direct marker, therapeutic target, or drug substrate[4][6][8]. - **No approved drugs** are designed to bind or inhibit FMN as a primary target[9]. No biomarker or safety profile information is associated, as it is not used as a target for therapy.

Other names

riboflavin-5'-phosphateriboflavine phosphateriboflavin phosphateflavine mononucleotideflavolflanin