ABSTRACT

Cryptococcus neoformans is an opportunistic fungal pathogen that causes cryptococcal meningitis, a potentially fatal infection that affects immunocompromised individuals, especially those with AIDS. According to the CDC, cryptococcal meningitis is responsible for 181,000 deaths worldwide each year. For infection by C. neoformans, the pathogen must survive in alveolar macrophages, the first defense mechanism in the lungs, which contain limited amounts of glucose, forcing C. neoformans to survive on nonpreferred carbon sources, such as acetate. Therefore, researchers hypothesized that genes that are needed for acetate utilization aid in establishing cryptococcal infection and contribute to virulence. Gene CNAG_00236, which had been previously deemed necessary for C. neoformans to survive on acetate, was investigated to determine possible protein functions using the online fungus database, FungiDB. Genes CNAG_05310, CNAG_07403, and CNAG_03697, which were all expressed more than log 2 higher on acetate than glucose, were also investigated to determine the possible protein functions of enzymes coded by these genes. As the current treatments for cryptococcal meningitis are not always effective, identifying genes in C. neoformans that are required for the fungus to grow on acetate may be an important step in the development of more effective treatments for cryptococcal meningitis.