Biochemistry Commons^™

Advances In Amino Acid Analysis For Marine Related Matrices And Its Application To Coastal Shelf Settings In The Canadian Arctic, Rachel M. Mcmahon

OES Theses and Dissertations

Amino acids comprise up to 50% of organic matter in cellular material and are a major fraction of oceanic organic carbon. Amino acids are also considered highly labile during organic matter recycling, making them useful proxies for organic carbon cycling. Nevertheless, analysis of individual amino acids has been burdened by lengthy derivatization and complex analysis since the 1950s. In this thesis, I describe the modification of advanced analytical techniques, developed in the biomedical field, for analysis of marine matrices which allow the determination of at least 40 amino acids without the need for lengthy sample preparation and derivatization, twice the …

Comparison Of Two Separation Methods For Biological Particles: Field-Flow Fractionation (Fff) And Sucrose Density Gradients, Cody E. Garrison

OES Theses and Dissertations

Sucrose gradient centrifugation and Field-flow fractionation (FFF) are two different particle separation methods that overcome the problems of similar size microorganisms clumping together during standard filtration methods. FFF separates particles based on size and density via the parabolic velocity profile of laminar flow in a ribbon-like channel. The sucrose method separates particles via centrifugation in a density gradient. Both techniques worked well in separating eukaryotic from prokaryotic microbes, with the preferred method depending on the type and relative abundance of organisms to be separated. Minicells were separated from mother cells in transformed Escherichia coli cultures, heterotrophic flagellates (e.g., Diplonema papillatum …

Phosphorus Uptake In Rhodomonas Salina (Wislouch) And Its Effect On Allocation And Elimination In Acartia Tonsa (Dana), Danna Palladino

OES Theses and Dissertations

Phosphorus is a key element in important biochemical compounds, such as RNA and phospholipids, and can become limiting in a variety of marine systems. The uptake of phosphorus into biochemical fractions (protein, low molecular weight (LMW) compounds, lipid, polysaccharide and nucleic acid) in Acartia tonsa fed ³³P -labeled Rhodomonas salina was examined. R. salina was cultured on two variations of one media that in one case contained phosphorus in balance and the other out of balance with relation to other standard f/2 components. The P-balanced (PB) media had a N:P ratio of 24.5, which is higher than that found …

Nitrate Reductase Activity, Nitrate Uptake And Iodine Speciation In The Marine Environment, Chin-Chang Hung

OES Theses and Dissertations

The present method for the determination of new production (NP) by measuring the uptake of added ¹⁵NO₃^– suffers from a number of limitations. In an attempt to improve this situation, this research examined the possibility of estimating ¹⁵NO₃– uptake by measuring the activity of nitrate reductase (NRA). In addition, because it has long been suspected that the biological reduction of IO₃^– to I^– may be mediated by nitrate reductase (NR), this research investigated the ability of NR to catalyze the reduction of iodate to iodide.

An improved method for the determination …