ROLE OF CALCIUM IONS IN THE STIMULATION OF GROWTH OF VIRULENT STRAINS OF PASTEURELLA PESTIS

Abstract
Virulent strains of P. pestis required rather high amounts of calcium ions (0.004 [image]) for good growth at 37[degree]C in a defined medium. Of 9 virulent strains tested, all were markedly stimulated at 37[degree]C by calcium ions. No stimulation of growth was observed at 27[degree]C. Avirulent strains, on the other hand, grew well at either temperature without the addition of calcium ions.