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Gelatin Hydrolysis This test is to determine the ability of bacteria to degrade gelatin (a protein). The result of protein degradation is the liquification of media that is made solid by the addition of gelatin instead of agar. This is called gelatin hydrolysis. The media used is Nutrient Gelatin an undefined medium containing sullicient nutrients but no carbohydrate. It is inoculated by stabbing directly into the center of the tube with an inoculating needle. The tube is incubated at room temperature in order to keep the gelatin from melting. Positive gelatin hydrolysis is shown by a liquification of the media, usually shown at the surface. It may take as long as a week for this to show up. Three Nutrient Gelatin deeps are inoculated with these organisms: E. coli, Bacillus sp. Micrococcus luteus. Hypothesis Formulate a hypothesis regarding each of the bacteria and their ability to degrade gelatin. RESULTS After incubation at room temperature, the tubes should be inspected for liquification. Due to the relative low temperature of the incubation, results may not be valid until a week. Questions: (-) (+) 10. Why is the incubation temperature less than 37C? 11. What type of molecule is gelatin? 12. Are the microbes fermenting gelatin? 13. Gelatin liquefies due to what microbial action?