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Date of Award

Spring 2008

Document Type

Restricted Thesis: Campus only access

Degree Name

Bachelor of Science



First Advisor

Dr. Laura Runyen-Janecky


Shigella flexneri is an intracellular bacterial pathogen which causes bacillary dysentery in humans and higher primates. When Shigella is inside of a human cell, there is an increase in the amount of transcription of the bacterium’s suf genes. The goal of the first study was to determine if the negative regulation of the suf gene by the Fe-Fur protein is reinstated when the fur gene is added back to a fur null mutant. The resulting data showed that the addition of the fur gene to the fur mutant, UR010, does restore the negative regulation of suf gene expression in high iron media. The second goal of this study was to determine if positive regulation of the suf gene by the IscR protein, as seen in Escherichia coli, takes place in Shigella. To this end, an iscR deletion mutant, UR027, was created in Shigella and was used in lab n of suf expression by oxidative stress. This serves as evidence supporting the hypothesis that IscR is a positive regulator of the suf gene.