Growth and siderophores production in Alcaligenes faecalis is regulated by metal ions

Abstract

During stationary phase of growth under low stress of iron in succinic acid medium, Alcaligenes feacalis BCCM ID 2374 produced microbial iron chelators. Increase in iron concentration supported bacterial growth but suppressed siderophores production, 1 μM and 2 μM of iron was optimum for maximum siderophore yield, i.e. 354 and 360 μg/ml in untreated and deferrated medium, respectively. Threshold level of iron, which suppressed siderophores production in A. feacalis BCCM ID 2374, was 20 μM. Ten micromoles and above concentration of CuCl2 and CoCl2, and 20 μM of MgCl2, MgSO4, ZnCl2 and ZnSO4 severely affected siderophores production. © 2009 Association of Microbiologists of India.