ACETATE AND OLEATE REQUIREMENTS OF THE LACTIC GROUP OF STREPTOCOCCI

Abstract

Addition of Na acetate and sorbitan monooleate permitted growth through serial transfers of 22 strains of Streptococcus cremoris and 9 strains of S. lactis which failed to grow in the unsupple -mented defined medium of Niven (Jour. Bact. 47: 343. 1944). 22 strains of S. lactis grew in the unsupplemented medium, although acetate and oleate were stimulatory for all cultures on which they were tested. Reticulogen, a commercial liver extract, could be substituted in somewhat smaller quantities for acetate and oleate and also permitted rapid growth of one strain of S. cremoris that did not show detectable growth until after 24 hrs. in the medium supplemented with acetate and oleate. Vitamin B12 was not required by any of these organisms.