Flavodoxin (Fld)

Flavodoxins are small, soluble electron-transfer proteins found in bacteria and some algae, but notably absent in vertebrates, including humans [2, 6]. They contain a non-covalently bound flavin mononucleotide (FMN) cofactor and function as isofunctional replacements for ferredoxin, particularly under iron-limiting conditions [6, 10]. In pathogens like Helicobacter pylori, flavodoxin is essential for survival as it shuttles electrons in the pyruvate:ferredoxin oxidoreductase (PFOR) complex, which is critical for energy metabolism [1, 2]. Because of its essentiality in certain pathogens and its absence in humans, flavodoxin is a promising therapeutic target for treating infections such as gastritis and peptic ulcers [2, 4]. Experimental inhibitors, including benzoxadiazol and nitroethylene derivatives, have been developed to bind a unique pocket near the FMN site, effectively blocking electron transfer and exhibiting bactericidal activity [1, 5]. These inhibitors show high specificity for H. pylori due to a unique alanine residue in the binding pocket that is not present in most other flavodoxins [1, 13]. Targeting flavodoxin offers a novel mechanism to combat antibiotic-resistant strains of H. pylori, which are increasingly prevalent worldwide [2, 5]. Research also suggests that anti-flavodoxin antibodies could serve as biomarkers for H. pylori-related conditions like MALT lymphoma [2, 13].

Other names

PhytoflavinFldAFldBFlavoprotein

Inhibition of electron transfer by binding to a specific pocket near the flavin mononucleotide (FMN) cofactor, thereby disrupting essential metabolic pathways such as pyruvate decarboxylation [1, 4].