Analytical Oral Presentations

Signal Enhancement of Lantibiotics Using Capillary Electrophoresis

Dever, Brittany

  • Brittany Dever, Kingsley Donkor*
  • Organization: Thompson Rivers University
  • Funding: NSERC-USRA, TRU-CUEF

Abstract: Lantibiotics are a unique group of peptides that are produced by gram positive bacteria and exhibit antimicrobial properties. Lantibiotics are interesting bacteriocins to study as they offer an attractive alternative to conventional antibiotics, especially in cases where antibiotic resistance is experienced. Nisin is a Class 1A lantibiotic that is commonly used as a preservative in dairy products. Gallidermin is also a Class 1A lantibiotic that is used for the treatment of acne, follicultis, impetigo and eczema. Both of these lantibiotics are similar in that they both are elongated peptides with a net positive charge associated. Capillary electrophoresis (CE) is a powerful analytical methodology based on its high separation efficiency, high analysis speed, low consumption of samples and ease of automation. However, one problem associated with the use of CE is its low concentration sensitivity. One way to improve the concentration sensitivity of CE is the use of a technique called large volume sample stacking (LVSS). This technique has shown to be successful in lowering the detection limit of several peptides found in human body fluids. The purpose of this project is to investigate the possibility of using LVSS/CE to lower the concentration detection limit and separate Class 1A lantibiotics, nisin and gallidermin. This in turn will afford the detection of small quantities of nisin and gallidermin in food and biological samples. In this presentation, current results will be discussed. This includes the conditions used to achieve enhancement of the detection and separation of nisin and gallidermin.

Indentification and Quantification of Naphthenic Acids in Oilsands Process-Affected Waters and Natural River Waters

Grewer, David

  • David Grewer, Rozlyn Young*, Phil M. Fedorak*
  • Organization: University of Alberta
  • Funding: Canadian Water Network, NSERC

Abstract: The extraction process used to recover bitumen from the Alberta oilsands releases toxic naphthenic acids into oilsands process-affected waters and tailing ponds that result. Naphthenic acids are described as carboxylic acids with general formula CnH2n+ZO2, where n gives the number of Carbons in the structure and Z describes the hydrogen deficiency, generally in terms of ring closured in the molecule. Oilsands process-affected waters are disposed of through the implementation of artificially constructed settling ponds resulting from the extraction process. Accurate and reliable methods for determining the naphthenic acid concentration in these ponds are necessary in order to gauge the condition of such waters in terms of reclamation. The study presented here evaluates the reliability and accuracy of the current industrial method of naphthenic acid detection using FTIR through comparison with gravimetric and GC-MS methods. A non-quantitative method using high resolution mass spectrometry is also proposed allowing discriminate identification between the two classes of water sources studied, oilsands process0affected water and fresh river sources.

Tweaking the Backbone: Tuning DNA Stability to Generate Catalytic Properties

Lam, Jade

  • Jade Lam, R. Bogel, A. Tang, J. M. Gibbs-Davis*
  • Organization: University of Alberta
  • Funding: UofA, NSERC, Province of Alberta

Abstract: Biological systems can achieve very specific interactions due to their ability to recognize certain molecules. Molecular recognition of DNA can be used to bring together fragments of complementary sequences onto a larger DNA strand allowing the fragments to be linked together in a process called ligation. In natural DNA, one long strand can template the ligation of two fragments at which point the template and the newly formed long strand remain hybridized due to the high stability of the duplex. Our goal is to tweak the stability of this duplex to encourage separation so the template strand can be used in another ligation reaction. This tweaking involves inserting destabilizing groups into the DNA template that will decrease duplex stability. Using five different destabilizing groups in the template strand and an enzyme to ligate the DNA, this method has been successful in tuning DNA stability to generate catalytic turnover of up to 16 ligation reactions per template strand. This catalytic turnover can be used to amplify DNA sequences, which is especially important in DNA detection.

Spatial and Temporal Pb, Zn, Fe, and Cu Contamination at a Mine in Canada’s Far North

Ramsay, Kevin

  • Kevin Ramsay, R W Thring*
  • Organization: UNBC
  • Funding: UNBC

Abstract: The concentrations of heavy metals (Fe, Zn, Pb, and Cu) in the foliage of fireweed (Epilobium angustifolium), Labrador tea (Ledum groenlandicum) and willow (Salix sp.), as well as, in the tree rings of black spruce (Picea mariana) in the vicinity of the Faro Mine Complex Faro, YT were determined using Inductively Coupled Plasma-Optical Emission Spectroscopy. High concentrations of lead, zinc, and iron were present at many sites throughout the mining area, however, sites that were not immediately next to a pollution source seemed largely unaffected. Dendrochemical analysis of tree ring concentrations indicated that zinc concentrations in black spruce began to increase and decrease almost immediately after the start and cessation of mining activities while lead appeared to have a slower response time. Black spruce was found to be a good bio-indicator for determining temporal pollution of lead and zinc; however, it was unreliable for iron while copper concentrations were too low to permit evaluation.