GROWTH-KINETICS OF A BACTERIOPHAGE IN CONTINUOUS-CULTURE

Lytic coliphage Q beta was grown in continuously cultured host bacteri a using a cascade of stirred flow reactors. The apparatus was construc ted so that the steady stream of exponentially growing bacterial cells passing through the stirred flow reactors served to prevent coevoluti on brought about by host-parasite interactions. Wall growth was the pr imary cause for deviation from ideal continuous culture conditions and is largely dependent on the surface structure of the host bacteria. U sing an Escherichia coil strain deficient in adhesive type I pili expr ession, the desynchronization of single burst events could easily be f ollowed over the course of four infection latency periods. Computer si mulations based on a two-stage model for the Q beta infection cycle we re in perfect agreement with the experimental data. Applications of th e optimized system to strategies of molecular evolution are discussed. (C) 1996 John Wiley & Sons. Inc.