My lab is focused on the mechanisms of spore germination and bile acid resistance in Clostridium difficile. C. difficile is a Gram-positive, spore forming, anaerobe that causes infections in people who have undergone antibiotic regimens. Previously, we had shown that certain bile acids promote C. difficile spore germination while others inhibit germination. Bile acids are small molecules made by the liver that help the absorption of fat and cholesterol in the GI tract while also serving as a protective barrier against invading pathogens. Because C. difficile spores use the ratios of bile acids as cues for germination, the actively growing bacteria must have adapted means to avoid their toxic properties. We are currently focused on identifying these factors and the mechanisms by which C. difficile spores germinate.
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