FIG 1.

Syntrophic growth of M. barkeri with G. metallireducens. (a) Metabolism of ethanol when the cocultures were initiated with a 5% (vol/vol) inoculum of each species. (b) Lack of ethanol metabolism with single species. (c) Decreased lag after 25 transfers (10% inoculum) of the cocultures. All cultures were grown in triplicate (n = 3). A difference in the y axis scale can be noted between panels a and b and panel c. This is because of differences in the total incubation volumes: 10 ml to initiate the cocultures (a, b) and 50 ml for later incubations (c).