Yesterday I had the privilege of working with Jenan Kharbush and Lihini
Aluwihare on their water pumping experiment. This particular experiment involved
a large pump and a smaller pump that were then attached to a wire and lowered
to the depths of 475m and 250m respectively. Once at these depths the pumps
were programed to turn on, pump and filter water for at most 4 hours. Each
pump had a two stage filter consisting of a pre-filter and a main filter. The pre-filter
was used to remove any large debris from the pumped water and keep it off
of the main filter. The main filter then trapped any microbial life that was present
in the water. The purpose of this experiment was to catalog any Bacteria found in the
water column and any differences that can be found at these two depths in the
mesopelagic zone. Later in the week, surface water will also be pumped and the bacteria found there will also be compared to those at lower depths.
Another experiment being conducted by these two scientist involves Archaea. These organisms are an important part of any water system because they preform a key process in the nitrogen cycle. They are the sole organisms responsible for turning ammonia into nitrite. For many years Archaea were mistakenly categorized as bacteria and placed in the same kingdom as bacteria, Monera. Only recently through more closely looking at the the genes and metabolic pathways has it been discovered that Archaea are more closely related to Eukaryotes than to Bacteria. Also, the Archaea’s reliance on ether lipids in their cell membranes sets them apart from Bacteria despite their absence of membrane bound organelles and similar morphologies. For these reasons many scientists today use a three domain system with Archaea in its own domain set apart from bacteria splitting Prokaryotes into two distinct groups. The experiment involves growing Archaea in dark incubators to find out if they will use the energy from ammonia to fix carbon into their structure and in what way it will incorporate it.