Component of the DprE1-DprE2 complex that catalyzes the 2-step epimerization of decaprenyl-phospho-ribose (DPR) to decaprenyl-phospho-arabinose (DPA), a key precursor that serves as the arabinose donor required for the synthesis of cell-wall arabinans (PubMed:16291675, PubMed:19299584). DprE1 catalyzes the first step of epimerization, namely FAD-dependent oxidation of the C2' hydroxyl of DPR to yield the keto intermediate decaprenyl-phospho-2'-keto-D-arabinose (DPX) (PubMed:22733761). The intermediate DPX is then transferred to DprE2 subunit of the epimerase complex, most probably through a 'substrate channel' at the interface of DprE1-DprE2 complex (PubMed:25789990). Can also use farnesyl-phosphoryl-beta-D-ribofuranose (FPR) as substrate in vitro (PubMed:25427196). Appears to be essential for the growth and survival of M.tuberculosis (PubMed:12657046, PubMed:24517327). DprE1 is a highly vulnerable and fully validated tuberculosis drug target. FAD + H(+) + trans,octa-cis-decaprenylphospho-beta-D-ribofuranose = FADH2 + trans,octa-cis-decaprenylphospho-beta-D-erythro-pentofuranosid-2-ulose Is inhibited by 8-nitro-benzothiazinones (BTZs) such as BTZ043 and PBTZ169; BTZs are a new class of antimycobacterial agents that kill M.tuberculosis in vitro, ex vivo, and in mouse models of tuberculosis (PubMed:20828197, PubMed:19299584, PubMed:22733761, PubMed:24500695). Is also inhibited by dinitrobenzamide derivatives (DNBs), which thus block formation of both cell-wall lipoarabinomannan and arabinogalactan via inhibition of decaprenyl-phospho-arabinose (DPA) synthesis; DNBs show high activity against intracellular growth of M.tuberculosis inside macrophages, including extensively drug resistant (XDR) strains (PubMed:19876393). BTZs and DNBs are suicide inhibitors that act via covalent modification of DprE1; the essential nitro group of these compounds is reduced by DprE1 to a nitroso group, which then specifically reacts with Cys-387 of DprE1 to form an irreversible semimercaptal adduct (PubMed:20828197, PubMed:22733761, PubMed:24500695). Many other compounds with diverse scaffolds were found to act as either covalent (e.g. nitroquinoxalines, nitroimidazoles) or non-covalent (e.g. the benzothiazole derivative TCA1, the 2-carboxyquinoxaline Ty38C, 8-pyrrole-benzothiazinones, 1,4-azaindoles, pyrazolopyridones, 4-aminoquinolone piperidine amides) DprE1 inhibitors (PubMed:23776209, PubMed:25427196, PubMed:25987616, PubMed:24215368, PubMed:24818517, PubMed:27666194). kcat is 4.1 min(-1) with farnesyl-phosphoryl-beta-D-ribofuranose as substrate (at pH 8 and 30 degrees Celsius). Cell wall biogenesis; cell wall polysaccharide biosynthesis. Monomer. Although forming apparent dimer in crystals, DprE1 does not dimerize appreciably in solution (PubMed:22733761). Interacts with DprE2 to form an epimerase complex (PubMed:25789990). Traditional knockout mutant with dprE1 disruption could not be achieved, suggesting this gene is essential (PubMed:24517327). Conditional knock-down mutant of dprE1 show that down-regulation of DprE1 results in rapid in vitro growth arrest, swelling of the bacteria, cell wall damage, stop of cell division or lysis, decreased survival in macrophages and virulence attenuation (PubMed:24517327). Cells lacking this gene display impaired growth (PubMed:12657046). Was identified as a high-confidence drug target. Belongs to the DprE1 family.