Bacterial competition for methylamine: Computer simulation of a three-strain continuous culture supplied continuously or alternately with two nutrients

Computer simulations were done of the competition between obligate methylotroph B6/2, facultative methylotroph DT26 and methazotroph NB4 in continuous cultures either supplied simultaneously with methylamine, glucose and ammonium or supplied alternately with methylamine and glucose/ammonium. In simulated cultures constantly supplied with methylamine, glucose and ammonium, the facultative methylotroph was retained in cultures, along with the methazotroph, only at dilution rates below 0.05 h⁻¹. In cultures alternately supplied with methylamine and glucose/ammonium the facultative methylotroph dominated the population and excluded both the obligate methylotroph and the methazotroph up to dilution rates near to its maximum specific growth rate on methylamine.