The role of trace elements and phosphates in the synthesis of vascular-permeability factor by Vibrio cholerae.

Trace element and phosphate requirements for the synthesis of vascular-permeability factor (PF) by Vibrio cholerae strains B1307 and VC12 were investigated. While magnesium appeared to be indispensable for strain VC12, small amounts of PF were synthesised by strain B1307 in the presence of iron, zinc and manganese. However, even in the latter strain, maximum synthesis was recorded only in magnesium-containing media. Phosphates in the range 0.75-6.00mM controlled the synthesis of PF by both strains.