Xcvii . the Nutrition of Staphylococcus Aureus ; Nicotinic Acid and Vitamin B 1 by Bert Cyril

HITHERTO Staphylococcus aureus has not been grown in media of completely known chemical composition. With a medium in which most of the nutrients were known (amino-acids and glucose) it has been necessary to add a supplement, quantitatively very small but qualitatively essential, before growth can occur. The necessity for the supplement was first shown by Hughes [1932] and later by Knight [1935], who used autolysed yeast extract (marmite) as a rich source of the growth factor and acid-hydrolysed gelatin plus glucose as the deficient basal medium. Subsequently it was found possible [Fildes et al. 1936] to substitute a collection of amino-acids plus glucose for the gelatin hydrolysate basal medium. The present paper shows that the active concentrate from yeast obtained by Knight, which must be given to S. aureus for growth to take place, can be replaced by nicotinic acid and vitamin B1 together, neither alone being effective. It is therefore now possible to grow a typical strain of S. aureus on a medium containing only known chemical components.