Presenters: Alexander Rich
Authors: Alexander Rich, Dylan Tatarian
Faculty Advisor: Elizabeth Pierce
Institution: Southern Utah University
Cryptobiotic crust is found on many desert soils. It is made up primarily of cyanobacteria, fungi, and various prokaryotes in smaller quantities. Species vary depending on whether the crust has been recently disturbed. Among other roles, cryptobiotic crusts protect the underlying soil from erosion and fix nitrogen gas into organic compounds needed by other organisms for growth. Molybdenum-dependent enzymes are central to nitrogen fixation and nitrogen metabolism. In a previous study, a part of the Beaver River basin northwest of Milford Utah was found to have a wide variation in molybdenum concentration, between 0.02 mg and 50 mg per kg of soil. Within a smaller section of the study area, molybdenum was found to be more concentrated in soil close to sagebrush roots and more concentrated in cryptobiotic crust samples than in the underlying soil. This study is comparing five cryptobiotic crust samples from areas of the Milford study site with low and high concentrations of molybdenum. DNA isolated from these samples will be submitted for metagenomic sequencing. The organismal composition of each sample will be analyzed, and we will analyze possible molybdenum needs in cryptobiotic crusts by looking for sequences homologous to known molybdoenzymes. Parallel to DNA isolation, metal contents of each sample and samples of surrounding soil will be determined by ICP-MS.