EFFECTS OF CARBON DIOXIDE ON THE COLONIAL GROWTH OF PATHOGENIC LEPTOSPIRAE

Yanagawa , R. (National Institute of Animal Health, Kodaira, Tokyo, Japan),T. Hiramune, and J. Fujita . Effects of carbon dioxide on the colonial growth of pathogenic leptospirae. J. Bacteriol.85: 875–880. 1963.—The growth of colonies of pathogenic leptospirae was examined in air of various CO2 concentrations, ranging from air from which CO2 was absorbed to air with 20% CO2 added, and was compared with the growth of other microorganisms of the generaMycoplasma, Brucella, Vibrio, Erysipelothrix, Staphylococcus, Micrococcus, Sarcina, Klebsiella, Salmonella, Escherichia , andBacillus . The colonial growth of the 24 strains of pathogenic leptospirae examined was similar to that of other organisms in that the growth was negative in air from which naturally contained CO2 had been absorbed, the growth tended to be inhibited in 5 to 20% CO2 in proportion to the CO2 concentration, and good colonial growth of leptospirae was obtained in a relatively narrow range of CO2 concentration (from the normal amount in air to around 1%). The growth of some leptospirae was accelerated in 1% CO2 , but not that of the strains ofLeptospira icterohaemorrhagiae , which required a lower range of CO2 , and ofL. canicola . The CO2 requirement of pathogenic leptospirae was similar, to some extent, to that ofMycoplasma mycoides , but was not so high as that ofBrucella abortus . Incorporation of C14 O2 was demonstrated in leptospirae.