FIG. 2.

The bacterial fraction stimulating the gastrin promoter is heat stable. (A) Fractionation scheme for the bacterial mixture. The PBS wash (Wash), WCS, and supernatant from the WCS were heated to 80°C for 15 min. The HS represents the activity after pelleting insoluble protein (Pellet) at 10,000 rpm for 15 min. (B) Fifty micrograms of the various fractions was used to stimulate stable transformants that express the human gastrin reporter construct. The relative induction ± standard error for at least four experiments is shown. C, control. (C) The indicated fractions were resolved on a 4 to 12% gradient gel and then stained with Coomassie blue dye. Lane M shows molecular mass markers. Ht, heated.