Hello everyone! My name is Alex Bianco and I am undergraduate student pursuing a degree in oceanography from Humboldt State University. Over the next two months I’ll be working together with Dr. Zhanfei Liu and Kaijun Lu here at the Marine Science Institute in Port Aransas, Texas. We will be observing how naturally occurring bacteria, found in the Lydia Ann Shipping Channel, metabolize 15N-alanine. This left-handed amino acid is one of the simplest primary amino acids and is found naturally and as an ingredient in fertilizer. As a result of metabolic processes the 15N-alanine can be transformed into a number of different molecules. Some of these molecules, like ammonium and nitrate, are relatively easy to quantify and are essential to our understanding of coastal nutrient fluxes. However, some of the chemical species produced fall under the category of dissolved organic nitrogen (DON) and are difficult to characterize. That is why DON is often calculated as the difference between total dissolved nitrogen (TDN) and dissolved inorganic nitrogen (DIN). The primary purpose of our experiment is to track how the concentrations of these molecules change over time. One unique aspect of our experiment is the method we selected to measure TDN. Through a process called UV oxidation we can liberate all the dissolved nitrogen from the water samples and transform it all into nitrate which can then be measured quantitatively. By analyzing how bacteria metabolize different amino acids we can learn more about what cause harmful algal blooms and how that can result in anoxic, or oxygen depleted, environments.