Improvement of Escherichia coli growth by kaolinite

Knowledge of the impacts of clay minerals on microorganisms is essential to a complete understanding of microbially-mediated processes. Information available in this regard remains scarce. Using Escherichia coli (E. coli) as a model bacterium, we investigated the effect of kaolinite on various growth parameters. This clay mineral significantly affected maximal growth rate and yield of the E. coli-strain (MG 1655) in minimum growth medium with 0.2% glucose, at an optimal concentration of 0.2 to 0.5 g/l. These physiological modifications were related to a decrease in catabolic activity and increased acetate assimilation via an energy transfer from acetate degradation to cell division rather than maintenance.