Coenzyme F420-dependent redox enzyme (F420-dependent enzyme)

Coenzyme F420-dependent redox enzymes are a specialized group of oxidoreductases that utilize the deazaflavin cofactor F420 to facilitate hydride transfer reactions (Greening et al., 2016). These enzymes are predominantly found in methanogenic archaea and a limited number of bacterial lineages, including the pathogen Mycobacterium tuberculosis (Cellitti et al., 2012). In clinical medicine, the F420-dependent nitroreductase (Ddn) is of paramount importance as it serves as the activating enzyme for the nitroimidazole class of antibiotics, such as pretomanid and delamanid (Manjunatha et al., 2006). Upon binding these prodrugs, Ddn catalyzes their reduction to generate reactive nitrogen species, which subsequently inhibit mycolic acid biosynthesis and disrupt mycobacterial respiration (Stover et al., 2000). Since coenzyme F420 and its associated enzymes are absent in human cells, they provide a highly selective therapeutic window for treating multi-drug resistant tuberculosis. However, the emergence of resistance is a significant concern, often driven by mutations in the genes responsible for F420 biosynthesis or the Ddn enzyme itself (Haver et al., 2015). Beyond drug activation, these enzymes play diverse roles in microbial metabolism, including methanogenesis and the degradation of environmental pollutants (Greening et al., 2016).

Other names

F420-dependent oxidoreductaseDeazaflavin-dependent enzymeF420-dependent nitroreductaseDdnF420-dependent glucose-6-phosphate dehydrogenaseFgd1Deazaflavin-dependent nitroreductase

Reductive activation of nitroimidazole prodrugs to generate reactive nitrogen species (e.g., nitric oxide) that inhibit mycolic acid synthesis and cellular respiration (Manjunatha et al., 2006; Stover et al., 2000).