GROWTH OF GROUP A HEMOLYTIC STREPTOCOCCUS IN THE STEADY STATE

Publisher Website
Google Scholar
Abstract
The steady-state growth of a group A hemolytic streptococcus (Streptococcus pyogenes type 4) was investigated by use of the continuous culture technique, i.e., continuous dilution at constant volume. The apparatus and medium developed for this purpose together with the associated operating procedures are described in detail. It has been possible to establish steady-state growth over a wide range of growth rate, 0.25 to 1 hour-1, and to maintain the steady-state conditions for at least 78 generations. Some features of the steady-state cultures have been studied for pH -limited growth, glucose-limited growth and tryptophan-limited growth. In the first case there is a characteristic relation between the growth rate and the steady-state pH. The rate of glycolysis has been found to decrease less rapidly with pH than does the growth rate with the result that the efficiency of utilization of glucose increases with increasing growth rate. The metabolite-limited cultures have higher, and non-characteristic, pH values than the pH-limited cultures. The metabolite-limited cultures reveal several distinctive properties which can be related to the low steady-state concentration of the limiting metabolite.

This publication has 6 references indexed in Scilit: