The complex ferri-pyoverdine acts as a signaling molecule inducing the production of secreted virulence factors in Pseudomonas aeruginosa. Ferri-pyoverdines promote the growth of both P. fluorescens and P. aeruginosa in minimal medium.
Pyoverdines, also called pseuobactins and pyoverdins, are fluorescent siderophores that have high affinity for iron (1032 M-1), and are synthesized by fluorescent pseudomonads under iron-deficient growth conditions. Pyoverdines were shown to prevent iron toxicity produced by iron overload in hepatocyte cultures and effectively scavenges the hydroxyl and peroxyl radicals. Pyoverdines are effective in acquiring iron from transferrin and lactoferrin. Pyoverdines are also involved in the suppression of pythium-induced damping-off of tomato and promotion of growth in some higher plants.
Supplied as a mixture containing mainly the succinic acid (MW=1161), 2-hydroxy glutaramide (MW=1190), and succinamide (MW=1160) forms of pyoverdines, bound to iron.