Incorporation of l-lysine and 2,2′-dipyridyl in the growth media promotes desferrioxamine E production by an actinobacterium

The study describes the use of the chelating agent 2,2′-dipyridyl in conjunction with lysine to increase the production of the siderophore desferrioxamine E by a previously described actinobacterium 23F. Desferrioxamine E is a type of siderophore known to be produced by Streptomycete species. Lysine is a precursor of the siderophore and its presence in the culture medium is known to promote desferrioxamine E synthesis. The further addition of 2,2′-dipyridyl was found to enhance production of the siderophore in the presence of lysine (5 g l −1 ) nearly twofold when incorporated at a concentration of 200 μM. Increasing the concentration of the chelating agent above 200 μM resulted in a decrease in siderophore production. The role of the chelating agent was thought to be in creating iron-limiting conditions in the culture medium and so promoting the induction of the desferrioxamine E biosynthetic pathway. This medium is likely to be a useful tool in the screening for producers of desferrioxamine E.