A Method for the Determination of the Culture Cycle and the Growth Rate of Virulent Human Type Tubercle Bacilli

Abstract

By the use of micro-Kjeldahl N detns., the culture cycle of the virulent human type tubercle bacillus, strain H37Rv, was detd. From the logarithmic portion of the growth curve, the growth rates and generation times are calculated. Under the conditions of the expt. the generation times were found to vary between approx. 11/2 and 31/2 days. The usefulness of the method for accurately determining the amt. of growth of tubercle bacilli the effect on the rate of growth or alteration of the composition of the medium and the presence of growth-inhibiting substances is illustrated.