Culturing Cold Prokaryotes:
A primary objective of the McMurdo Dry Valleys MO is to obtain cultures of prokaryotes that drive the major nutrient cycles (C, N, S) in the dry valley lakes.
The Madigan lab is using both conventional enrichment procedures and extinction dilution techniques at cold temperatures to pursue anaerobic and aerobic organisms from the dry valley lakes.
Work on molecular phylogeny by the Madigan Lab will yield the first catalog of prokaryotic diversity from the southern-most lakes on our planet and the only lakes on Earth with permanent ice covers. Molecular phylogeny studies will be used to accomplish three goals. First, these data will be used to characterize the microbial diversity of the dry valley lakes. Second, oligonucleotide probes targeting frequently retrieved sequence groups will be developed and used to determine the distribution of these groups over time and space. Third, these oligonucleotide probes will be used for fluorescence in situ hybridization (FISH) to monitor enrichment and the high throughput cultures.
The Giovannoni Lab is using a novel approach known as high throughput culturing to obtain organisms from oligotrophic environments.