Question

Imagine that you are part of a lab group planning a metagenomic survey of microbial life living inside the liquid found in pitcher plants (carnivorous plants) found in bogs in Michigan. You're asked to design an experiment using only filters that will enrich for three samples: A) Eukaryotic cells; B) Archaeal and Bacterial cells; and C) Viruses.

A) Describe a filtering protocol (be specific about filter pore size) that will successfully generate the three enriched fractions described above. You may use more than no more than TWO filters for your experimental design.

B) Briefly describe the logic behind the above experimental design.

C) Would you be able to completely remove the viral DNA present in the Bacterial/Archaeal fraction via a filter? Explain why or why not in the space below.

Answer 1

Answer A&B) To separate eukaryotic cell, bacteria, archaea and viruses, two filter could be used consequently (1) with 0.45 micron pore size and (2) with 0.22 micron pore size. The 0.45 micron pore size filter will separate eukaryotic cell from bacteria/archaea and virus fraction. Now, when this fraction would be passed through 0.22 micron pore size filter, the bacteria/archaea will be separated with virus fraction. Thus the three fraction will be successfully generated.

Answer C) Yes the viral DNA present in bacteria/archaea fraction can be separated via 0.22 micron pore size filter. This will pass the viral DNA through pore because of smaller size and will retain the bacteria/archaea fraction.