Functional and Molecular Diversity in Nitrogen Cycle Enzymes, What Genes are We Looking for?

Goals/Specific Aims:

1. Develop molecular tools to examine genes encoding N mineralization and immobilization enzymes through data-mining and bioinformatic analysis of existing resources. Extend the database of genes encoding the enzymes of N mineralization and immobilization for agricultural soil environments.
2. Analyze genomic information from two bacterial ammonia-oxidizing bacteria, Nitrosospira multiformis and Nitrosospira briensis. Analyze archaeal versus bacterial ammonia oxidizers for their functional gene diversity. Establish and maintain novel archaeal ammonia oxidizer enrichment cultures from soils and obtain metagenomic information from these enrichments. Further our understanding of the contrasting niche of archaeal and bacterial ammonia oxidizers and relate to the nitrification process in agroecosystems under contrasting management.
3. Use the novel molecular tools to examine the diversity and abundance of microorganisms responsible for selected N cycle processes in soils from contrasting agricultural systems. Assess relationships to process rates and kinetics in these systems.