Siderophore production by Fusarium venenatum A3/5.

Fusarium venenatum A3/5 was grown in iron-restricted batch cultures and iron-limited chemostat cultures to determine how environmental conditions affected siderophore production. The specific growth rate in iron-restricted batch cultures was 0.22 h(-1), which was reduced to 0.12 h(-1) when no iron was added to the culture. D(crit) in iron-limited chemostat culture was 0.1 h(-1). Siderophore production was correlated with specific growth rate, with the highest siderophore production occurring at D=0.08 h(-1) and the lowest at D=0.03 h(-1). Siderophore production was greatest at pH 4.7 and was significantly reduced at pHs above 6.0. Siderophore production could be enhanced by providing insoluble iron instead of soluble iron in continuous flow cultures.