Figure 3

The production and secretion of ADF-2 is shown as a function of time. In these experiments, each data point represents the time at which IPTG is added to the media and the titer is the amount of protein observed after 4 hours. A. Protein expression initiates by 4 hours and maximum production is achieved between 4-12 hours. Expression rapidly declines after 8 hours, indicating that the psicA promoter in inactive. B. ADF2 silk protein secretion measured with 4-hour resolution for up to 20 hours. C. The secretion efficiency of Type III Secretion, defined as secreted ADF2 protein divided by total expressed, over 20 hours. Each point is the average of three independent colonies and error bars represent +/- one standard deviation.