Other Biochemistry, Biophysics, and Structural Biology Commons^™

Structural And Functional Lessons Learned About Regulation Of Enterotoxigenic E. Coli Virulence Regulatory Factor, Rns, Jessica Dianne Tolbert

Dartmouth College Ph.D Dissertations

Antibiotic resistance has exacerbated the global health crisis of diarrheal diseases caused by enteric bacterial pathogens. Investigating pathogens, such as Enterotoxigenic Escherichia coli (ETEC) and Vibrio cholerae (cholera), helps to uncover mechanisms for the inhibition of virulence gene expression. A notable member of the AraC transcription factor family in ETEC, Rns, regulates virulence factors including pili and fimbriae, which are essential for adherence and colonization of the intestinal epithelial layer. This microbe–host interaction initiates the release of toxins, leading to the water and ion loss in clinically diagnosed as diarrhea.

In the canonical N-terminal domain of Rns, mutagenesis of the …

Atg23 Dimerization Drives Membrane Tethering In Yeast Autophagy, Kelsie A. Leary

Dartmouth College Ph.D Dissertations

All cells undergo stress throughout their lifetime, including single-celled bacterium or a single cell from a plant or a human. This stress can result in damage that can be detrimental to the cell if it is not removed. Thus, healthy cells require a tight balance between clearing damaged cellular material and its replenishment. Autophagy is a highly conserved process evolved by cells to encapsulate damaged material in a double membrane vesicle for its delivery to the lysosome (in mammals) or the vacuole (in yeast). Upon lysosomal delivery, the contents are degraded and returned to the cell for reuse. Autophagy can …