FIG. 3.

Production of tPA in a high-cell-density fermentation. The cell density, reported as OD₅₅₀, and the oxygen uptake rate (OUR) are shown together with the tPA specific activity data from samples taken 0.5 h before and 0.5, 1.5, 2.5, 3.5, 4.5, and 5.5 h after the addition of arabinose. The tPA activity was determined by the indirect chromogenic assay. Comparable levels of activity were obtained in different runs (n = 3).