Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Medicine and Health Sciences

Mutations To Antibiotic Resistance During Stringent Response In B. Subtilis, Chad Hansen, Ronald E. Yasbin, Eduardo A. Robleto Aug 2009

Mutations To Antibiotic Resistance During Stringent Response In B. Subtilis, Chad Hansen, Ronald E. Yasbin, Eduardo A. Robleto

Undergraduate Research Opportunities Program (UROP)

The relA gene in Bacillus subtilis controls a variety of factors during the stringent response which is a response to starvation of amino acids. The stringent response inhibits DNA synthesis and transcription of genes of tRNA, rRNA, and ribosomal proteins and promotes synthesis of the required amino acids. The objective of my project is to determine if a strain of B. subtilis that has a knockout mutation for the relA gene will accumulate a higher number of mutations that confer resistance to antibiotics that inhibit translation. It is proposed that because the relA gene inhibits transcription of ribosomal proteins, a …


Characterization Of The Omptin Protease, Ompt, In Escherichia Coli, Amanda Yates, Eun-Hae Kim, Helen Wing Aug 2008

Characterization Of The Omptin Protease, Ompt, In Escherichia Coli, Amanda Yates, Eun-Hae Kim, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Omptins are outer membrane proteases found in gram negative bacteria that cause diseases in humans, such as pathogenic Escherichia coli, Shigella flexneri, Salmonella typhimurium, and Yersinia pestis. Bacterial species that express omptins cause diseases such as highly fatal plague and severe diarrhea and dysentery. The genes that encode these proteases are ompT, icsP, pgtE, and pla, respectively. These proteases are highly related in structure and share approximately 50% sequence identity. In S. flexneri, IcsP has been shown to cleave a key virulence determinant, IcsA (Egile et al., 1997). IcsA recruits host actin and allows for intracellular movement within host cells …


The Effects Of Host Physiological Conditions On The Expression Of Icsp In Shigella Flexneri, Karen Levy, Helen Wing Aug 2008

The Effects Of Host Physiological Conditions On The Expression Of Icsp In Shigella Flexneri, Karen Levy, Helen Wing

Undergraduate Research Opportunities Program (UROP)

Shigella flexneri is a gram-negative bacterium capable of causing diarrhea and dysentery known as shigellosis. It is estimated there are 167.4 million shigellosis episodes throughout the world each year causing 1.1 million deaths. Shigella invades cells in the lower intestine through an induced phagocytosis. Once in the cytoplasm, bacteria move from one cell to another using actin-based motility. The Shigella outer membrane protease IcsP regulates actin-based motility and cell-to-cell spread by cleaving the actin assembly protein IcsA from the bacterial cell surface. We hypothesize that IcsP may serve additional functions during infection. By examining which environmental signals trigger icsP expression, …