Morphological, Physiological and Molecular Characterization of Two Fungi Isolated from the Yellowstone National Park
Two fungi were isolated from the Yellowstone National Park using Millipore filtration systems equipped with 0.22?m membrane filters. The filters were transported back to the lab, cut into small pieces, placed on Nutrient Agar plates and incubated at 37°C for 72 hours. Single colonies of YNP6-TSU and YNP7-TSU were selected and inoculated on new PDA media to have a pure culture for characterization. Three approaches were conducted to assist the identification process. The morphological assessment was done by using the agar block technique to examine the structure of the fungi and the spores without disrupting them. It was found that YNP6-TSU and YNP7-TSU had coenocytic hyphae and both produced asexual spores. YNP6-TSU asexual spores are septate conidia produced from the hyphae, while YNP7-TSU sporangiospores are produced inside the sporangium which being held up by the sporangiophore. To assess the effect of the temperature and pH, two approaches were conducted. To determine the optimal iv temperature, three agar media PDA, SDA and V8 were used to grow the fungi in 20, 25, 30, 37, 45 and 50 ºC for 10 days. To test the growth in higher temperatures, PDA broth media was used to grow fungi at 50, 55, 60, 65 and 70 ºC in water bath. It was concluded that at 37 ºC and with PDA as a media, the growth of both fungi was at a higher rate, while there was no growth at 50ºC or higher. As for the pH experiment, the fungi were grown in pH range from 2 to 9 at 37 ºC in three different media for 3 days in YNP7-TSU case and 10 days in YNP6-TSU. It was noted that YNP6-TSU optimal pH was 4 while YNP7-TSU optimal pH was 7. In the molecular process, fungi were grown on PDA for 7 days and mycelia were harvested for DNA extraction, PCR and sequencing. The results of sequencing and blasting showed 100% match for YNP6-TSU to Verruconis calidifluminalis and for YNP7-TSU to Rhizopus microsporus. Future studies will include extraction and purification of the brown pigment from Verruconis calidifluminalis (YNP6-TSU).
"Morphological, Physiological and Molecular Characterization of Two Fungi Isolated from the Yellowstone National Park"
ETD Collection for Tennessee State University.