FIGURE 4.

MccE492 region 54–63 and residues P57 and P59 control in vivo amyloid formation. MccE492 mutants of putative gatekeeper residues or lacking predicted aggregation hotspots were expressed in E. coli BL21-AI cells, followed by ThS staining. Bacterial cell populations carrying MccE492 amyloid inclusions (ThS-positive) were quantitated by flow cytometry. (A) ThS-positive population frequency upon expression of different MccE492 variants in the absence (top), or co-transformed with np220 (bottom). (B) Representative histograms of flow cytometry data obtained for cells expressing wild-type MccE492 or variants with altered aggregation propensity, either in the absence or co-transformed with np220. Error bars show the standard deviation from three independent experiments. ^∗∗∗p < 0.0001. An average of 10000 events were counted per flow cytometry run. p33AM is the vector in which the cassette pETAB was cloned.