Utilization of Carbon Compounds by Mycobacteria in a Synthetic Medium.

Abstract

The utilization of a number of carbohydrates, when added to plain broth as the basic medium, by organisms of the genus Mycobacterium was reported previously. 1 The method employed was limited to determinations of utilization of reducing sugars only. In order to determine the extent to which other carbon compounds were utilized, a synthetic medium has been used which contained the carbon compound under investigation as the sole carbon source. The appearance of growth and reaction change in the media were used as criteria for utilization.

Employing this method the extent of utilization of 16 carbon compounds by 14 strains of Mycobacteria has been studied. The results are summarized in Table I. The utilization is sufficiently varied that it becomes of some value in differentiating the organisms studied. There were some cases in which utilization could not be demonstrated by this method where the same carbohydrates were shown to be utilized by the same organisms in the carbohydrate broth cultures. 1

The reaction changes associated with growth of the organisms in the synthetic media were progressive increase in acidity in the carbohydrate and alcohol containing media, and a primary increase in alkalinity followed by a reversion of the reaction towards neutrality of the media containing organic acids.