The Mississippi River flows 2350 miles from its source at Lake Itasca in the northwest corner of Minnesota through the center of the continental United States to the Gulf of Mexico. While most of the wildlife in the river and along its banks is well documented, the microorganisms in the river were not.
As leader of the Minnesota Mississippi Metagenome Project (M3P), Michael Sadowsky, PhD is in the process of changing that by identifying and determining the function of each microbial species in the river. So far, they’ve identified 4000–6000 unique species through metagenomic sequencing with the HiSeq and MiSeq Systems. Many of these microorganisms can’t be grown, so next-generation sequencing was the only way to determine their taxonomic distribution. The Illumina sequencing systems “have the throughput that we needed to do a project of this magnitude,” said Dr. Sadowsky.
The study has yielded a few surprises. “We expected to find microbial diversity, but I didn’t expect it to be as great as what we found,” Dr. Sadowsky added. “We’ve seen that agricultural, urban, and forested land use impacts the types of microorganisms present. We also observed that the degree of resistance to antibiotics and heavy metals was a lot less than we thought it would be.”