Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Life Sciences
Diversity And Function Of Sulfur Cycling Microorganisms In Sediments From Subglacial Lake Whillans, Antarctica, Alicia Marie Purcell
Diversity And Function Of Sulfur Cycling Microorganisms In Sediments From Subglacial Lake Whillans, Antarctica, Alicia Marie Purcell
Masters Theses
There is a growing consensus that metabolically and phylogenetically diverse assemblages of microorganisms mediate subglacial nutrient and elemental cycling. Subglacial Lake Whillans (SLW), located under 801 m of glacial ice, was recently penetrated using environmentally clean protocols. SLW is a permanently dark, cold (-0.5 °C [degrees Celsius]), and shallow (~2.2 m) freshwater lake beneath the West Antarctic Ice Sheet. The presence and diversity of key functional genes involved in dissimilatory sulfur oxidation and reduction were examined at various depths in two sediment cores taken from SLW. Our data show a diversity of sulfur transformation genes throughout the top 34 cm …
Urea As A Nitrogen Source For Microcystis Aeruginosa, Bernard Shafer Belisle
Urea As A Nitrogen Source For Microcystis Aeruginosa, Bernard Shafer Belisle
Masters Theses
Over the last decade, Lake Erie has experienced annual harmful algal blooms events dominated by the toxic cyanobacterium Microcystis aeruginosa. It is still unclear what causes Microcystis blooms to occur, but there is broad agreement that eutrophication of freshwater systems from anthropogenic sources (urban, industrial, etc.), has led to their proliferation. In particular, the organic compound urea has been implicated as an important source of anthropogenic nitrogen, due to its increased use in agricultural practices. Currently, urea constitutes more than 50% of the nitrogen used for agricultural fertilizer globally, and its usage has increased more than a 100-fold over …
Examining The Nutritional Requirements Of Acidophilic Archaea "Ferroplasma Acidarmanus" Strain Fer1, Yudong Qu
Examining The Nutritional Requirements Of Acidophilic Archaea "Ferroplasma Acidarmanus" Strain Fer1, Yudong Qu
Masters Theses
Ferroplasma acidarmanus strain fer1 (fer1) is an archaeal microaerophilic acidophile (pH 0 to pH 3) with a chemolithotrophic metabolism. As an efficient consumer of sulfate, fer1 plays an important role in the biogeochemical process of pyrite dissolution at acidic site. Confirming the genomic prediction of metabolic gene functions in this organism requires functional assays, which cannot be carried out until a defined medium is obtained. The objective of the current study was to replace the 0.1% (w/v) yeast extract component in the growth medium, mfer, with defined components for carbon, nitrogen, and vitamin needs. In order to replace the 0.1% …