The Role of Histone H3K79 Methylation and Histone H4 Acetylation in the Saccharomyces cerevisiae UV-Induced DNA Damage Response

Indianapolis, IN

Serine hydrolases are a diverse class of enzymes that are essential to the toxicity of M. tuberculosis, the causative agent of tuberculosis. I have developed a method for measuring the cellular enzymatic activity of serine hydrolases in Mycobacterium smegmatis. M. smegmatis was used for the analysis, as many of the serine hydrolases are conserved with M. tuberculosis, but M. smegmatis is nontoxic to humans. In this analysis, M. smegmatis cultures are incubated with varying concentrations of a library of fluorogenic ester substrates. The library of fluorogenic ester substrates contains substrates with varying ester functionalities to determine the exact chemical reactivity of serine hydrolases in M. smegmatis. Substrates that were highly activated in M. smegmatis were then tested in other common bacterial strains for their relative activation profiles. Assignment of the substrate activation to the serine hydrolase activity was determined using serine hydrolase inhibitors. Using highly activated fluorogenic substrates, further work will compare the serine hydrolase profiles between different strains of some of the infectious Mycobacterium species to aid in diagnostics.