Based on these important observations, we employed both Agrobacterium-mediated insertional mutagenesis and bioinformatics to predict all the uric acid catabolic enzyme-encoding genes in the H99 genome. In addition, uric acid utilization enhances the production of the cryptococcal virulence factors capsule and urease, and may potentially modulate the host immune response during infection. Currently, relatively little is known about uric acid catabolism in the fungal pathogen Cryptococcus neoformans even though this yeast is commonly isolated from uric acid-rich pigeon guano. In contrast, uric acid is completely degraded to ammonia in most fungi. Uric acid in human blood plasma serves as an antioxidant and an immune enhancer conversely, excessive amounts cause the common affliction gout. In humans, most higher primates and birds, the urate oxidase gene is non-functional and hence uric acid is not further broken down. Degradation of purines to uric acid is generally conserved among organisms, however, the end product of uric acid degradation varies from species to species depending on the presence of active catabolic enzymes.
0 kommentar(er)
