Effect of metal ions on growth of Pseudomonas aeruginosa and siderophore and protein production.

Pseudomonas aeruginosa (GRC1) isolated from potato rhizosphere, grew better on succinate medium than tryptic soy medium and produced hydroxamate type of siderophore in iron-deficient succinate medium. When the strain GRC1 was grown in the presence of different metal ion compounds, viz. ZnSO4, MnSO4, MnCl2 and FeCl3 at 6 and 12 microM concentrations individually, ZnSO4 (12 microM) promoted siderophore production but suppressed the growth and protein content of test organism. MnCl2 and FeCl3 (12 microM) enhanced the growth, whereas MnCl2 and MnSO4 (12 microM) induced protein contents of strain GRC1.