Abstracts (71-81)

71) Julian Dupuis, Systematics and Evolution/Felix Sperling, Ph.D., oral presentation
Abstract Title: Hybrid zone dynamics of the Papilio machaon species group in western Canada

Hybrid zones provide unique natural laboratories to study the nature of species boundaries. Within these zones of contact, hybridization can result in an array of evolutionary outcomes depending on the strength of selection, hybrid fitness, patterns of gene flow, and environmental influences. These dynamics can promote or inhibit speciation, but our ability to predict these outcomes in natural systems is relatively limited. Here we characterize a hybrid zone between two species of swallowtail butterflies in western Canada using genetic data. Although the two species are found throughout Alberta and British Columbia, and can produce viable hybrid offspring, hybrid individuals were predominantly found in only a few central regions. The ancestry of these hybrids varied, and suggests complexity not only in recent hybridization, but also in the deeper evolutionary histories of these lineages.

72) Robert Lees-Miller, Microbiology/Feldman, M. Sc., Oral
Abstract Title: Substrate Promiscuity in Initiator Glycosyltransferase of Acinetobacter baumannii

Protein glycosylation, lipopolysaccharide, and capsular polysaccharide are all essential virulence factors for numerous bacterial pathogens. The oligosaccharide subunits used in creating these structures are assembled in the cytoplasm on a lipid scaffold, undecaprenylphosphate (UndP), by a series of enzymes known as glycosyltransferases. The initiating glycosyltransferase (iGT) is unique in transferring the first nucleotide phosphate activated sugar to UndP, and to date have been specific for the sugar they transfer. An iGT was identified in Acinetobacter baumannii that appears to be capable of transferring multiple sugars, however. In vivo models using complementation of deletions of other iGTs indicate transfer of multiple sugars possessing an N-acetyl group. Further validation is being developed using an in vitro model measuring a byproduct of synthesis, UMP, in a luminescent assay. Proof of promiscuity will allow for comparison between homologous, but specific, iGTs to d!
etermine the mechanism for sugar selection. It will also provide a platform and rationale for developing novel antibiotics against these poorly understood but essential bacterial proteins.

73) Eric Neilson, Ecology, Dr. Stan Boutin, Ph.D, presentation
Abstract Title: Predator prey dynamics in Alberta’s oil sands: Human disturbance mediates moose refuge from wolves

Refuge from predation can develop when predators avoid human disturbances more than their prey. Several researchers have demonstrated that wolves (Canis lupus) avoid human developments, whereas moose (Alces alces) are less sensitive to human disturbance than other ungulates. Alberta’s Athabasca oil sands (AOS) are characterized by extensive human disturbance of varying types and intensities. In this study, I will test for the presence of prey refuge around AOS that protects moose from predation from wolves. Specifically, I will test the prediction that because wolves avoid mines, locations of moose killed by wolves will increase with distance to mines. The Wildlife Habitat Effectiveness and Connectivity (WHEC) program at the University of Alberta outfitted 34 wolves from nine packs with GPS collars in 2012. I will estimate the locations of moose kills from clusters in wolf telemetry locations. Then I will compare the habitat and distance to mines between kills and random locations using resource selection functions. Understanding how human activities alter the spatial distribution and interactions of species will enable industrial and government regulators to plan regional land use strategies accordingly.

74) Margarita Bernal/Tracy Raivio/M.Sc./oral presentatin <mbernal@ualberta.ca>
Abstract Title: The Cpx envelope stress response leads to changes in the peptidoglycan structure by up-regulating ygaU, slt/mltB and ycbB

Bacteria need to adapt to the ever-changing conditions in the environment. E. coli employs the Cpx stress response to alleviate stress in the periplasm by causing an increase in chaperone and protease activity to restore cell homeostasis. The activity of the Cpx pathway is mediated by an inner-membrane histidine kinase (CpxA) and its cognate response regulator (CpxR).  We observed in a microarray analysis that the Cpx pathway has more functions than initially thought as the Cpx regulon was enriched for inner membrane-associated proteins and cell wall modification enzymes. The objective of this study was to determine the effect of the activation of the Cpx pathway on the structure of the cell wall. We first confirmed by luciferase assays that ygaU, slt70 and ycbB are highly up-regulated in the presence of Cpx inducing cues, suggesting that changes in peptidoglycan synthesis and cross-linking are important for survival of E. coli. Furthermore, ygaU, slt70 and ycbB are essentia!
l for wild-type-like resistance to various beta-lactams during Cpx activation.  Finally, we also observed that absence of ygaU, and ycbB can induce activation of the Cpx pathway, indicating that the structure of the cell wall might play and important role for Cpx activation.

75)  Amanda St.Onge
Abstract Title: Monitoring the pea leaf weevil (Sitona lineatus) with aggregation pheromone and host plant volatiles

The pea leaf weevil, Sitona lineatus (Coleoptera: Cucurlionidae), is an economically important pest of field pea Pisum sativum L. that is currently invading the Prairie Provinces. Larval feeding destroys Rhizobium-containing root nodules, reducing both pea yield and nitrogen fixation. Although the larva is the damaging stage, larvae live underground and are difficult to monitor. Adults, however, are active at the start and end of the growing season when they are attracted to aggregation pheromone and host plant volatiles. The objective of this research is to develop a semiochemical system for monitoring the ongoing invasion of pea leaf weevil. In 2013, we tested four release rates of pheromone alone and in combination with host plant volatiles. Lures baited with host plant volatiles were more attractive than pheromone alone. High doses of pheromone tended to be less attractive than low doses. In 2014, we will test combinations of two host plant volatile release rates and two pheromone release rates in both the field and in an olfactometer. Various traps types will also be tested to find the most suitable trap for capturing pea leaf weevils. The results of these experiments will be used to develop a semiochemical-based system for monitoring pea leaf weevils.

76) Ben Bourrie, Dr. Jon Dennis, 499, poster
Abstract Title: Environmentally Induced Changes in Virulence in Burkholderia multivorans C5274

Bukholderia multivorans is responsible for the highest number of Burkholderia cepacia complex infections among Cystic Fibrosis patients in North America, however very little is known about the virulence factors expressed by B. multivorans.  In past work using typical BCC infection models, B. multivorans has shown little to no virulence making it difficult to identify these factors.  Recent work with duckweed (Lemna minor) has shown that under physiologically relevant conditions, specifically low oxygen concentrations, B. multivorans exhibits significantly increased virulence.  By utilizing this new infection model to test a randomly generated mutant library of B. multivorans, we are able to identify mutants which are deficient in this environmentally activated virulence.  These mutants are then examined in order to determine any phenotypic changes resulting from the mutation as well as the specific genes and proteins involved in mediating this environmentally activated virulence.

77)  Mohamed Nasr, Dr Mario Feldman, M.Sc., oral presentation
Abstract Title: O-linked Protein Glycosylation in Acinetobacter baylyi: More Complicated than We Thought?

O-linked protein glycosylation is a post-translational modification system found in all domains of life. In bacteria, this system involves synthesis of the glycan structure by different glycosyltransferases in the cytoplasm, followed by its translocation into the periplasm. Then the glycan is transferred from a lipid carrier to serine or threonine residues of the acceptor proteins by the O-Oligosaccharyltransferase (O-Otase). Glycoproteins play key roles in bacterial motility, adhesion and immune evasion in the host among many others. (Nothaft & Szymanski, 2010)

Several glycosylation systems have been described where a single O-Otase glycosylates multiple substrate proteins. This includes previous work that has identified an O-Otase, ACIAD3337, in Acinteobacter baylyi ADP1, a non-pathogenic relative of the notorious hospital pathogen A. baumannii (Schulz et al., 2013). Recently, our lab has identified a homologue of this O-Otase in A. baylyi, ACIAD0103. We hypothesized that these two enzymes would exhibit different substrate specificities. We are also interested in characterizing the natural protein targets and glycan structures associated with each enzyme by utilizing a variety of mass spectrometry techniques.

Among the numerous applications of glycosylation, O-Otases could be utilized to generate recombinant glycoproteins with different proteins attached to the same glycan residues (Gebhart et al., 2012). These glycoconjugates could be utilized as vaccines and diagnostics for bacterial infections (Iwashkiw et al., 2012).

Gebhart, C., Ielmini, M. V., Reiz, B., Price, N. L., Aas, F. E., Koomey, M., & Feldman, M. F. (2012). Characterization of exogenous bacterial oligosaccharyltransferases in Escherichia coli reveals the potential for O-linked protein glycosylation in Vibrio cholerae and Burkholderia thailandensis. Glycobiology, 22(7), 962–74. doi:10.1093/glycob/cws059
Iwashkiw, J. A., Fentabil, M. A., Faridmoayer, A., Mills, D. C., Peppler, M., Czibener, C., … Feldman, M. F. (2012). Exploiting the Campylobacter jejuni protein glycosylation system for glycoengineering vaccines and diagnostic tools directed against brucellosis. Microbial cell factories, 11(1), 13. doi:10.1186/1475-2859-11-13
Nothaft, H., & Szymanski, C. M. (2010). Protein glycosylation in bacteria: sweeter than ever. Nature reviews. Microbiology, 8(11), 765–78. doi:10.1038/nrmicro2383
Schulz, B. L., Jen, F. E. C., Power, P. M., Jones, C. E., Fox, K. L., Ku, S. C., … Jennings, M. P. (2013). Identification of bacterial protein O-oligosaccharyltransferases and their glycoprotein substrates. (M. Skurnik, Ed.)PloS one, 8(5), e62768. doi:10.1371/journal.pone.0062768

78) Nicole Noel, Dave Pilgrim, GENET 420, poster.
Abstract Title: The Effect of Retinoic Acid on Zebrafish Six7

Development is a complex process involving the interactions of many genes in order to generate pattern. Retinoic acid (RA) is a signalling molecule involved in the regulation of patterning vertebrate tissues. Embryonic exposure to RA has an effect on anterior-posterior development in zebrafish; specifically, gene expression in the anterior of the embryo has altered expression after RA treatments. In an undergraduate laboratory course, the influence of retinoic acid on developmental genes was investigated using published microarray data by Feng et al. (2010) to choose relatively uncharacterized zebrafish genes that may be regulated by RA.
Zebrafish six7, a gene involved involved in patterning of the brain and retina, was reported as significantly down-regulated in the presence of RA. Six7 acts cooperatively with other six3-like genes, and has a partially redundant function with six3b; only double knockouts result in a phenotype, which is severe reduction of eyes and irregularity in dorsal-ventral patterning of the telancephalon (Carlin, 2012; Inbal, 2007). RA treated embryos showed a significant decrease in six7 mRNA via quantitative analysis, suggesting that six7 is controlled by the retinoic signalling pathway.

79) Pek Ly- Undergraduate 499, PI: Mario Feldman, oral presentation
Abstract Title: Regulation of type 6 secretion system of the bacterial pathogen Acinetobacter

The Gram-negative bacterium Acinetobacter baumannii is now established as a problematic opportunistic pathogen in hospitals. While A. baumannii does not usually pose a threat to healthy immunocompetent individuals, this pathogen is a frequent cause of pneumonia and soft tissue infection in immunocompromised patients in the healthcare setting. Much of the species’ infamy is derived from its ability to quickly adapt to its environment and many clinical isolates have been found to harbour horizontally acquired virulence genes, including drug resistance. The true virulence potential of A. baumannii has yet to be established and the mechanisms behind its continued success in hospital settings remain unclear. The emergence of multidrug-resistant (MDR) and pandrug-resistance strains in hospital infections necessitates the continued study of pathogenicity mechanisms in Acinetobacter species.
We analyzed multidrug-resistant clinical isolates obtained from a recent outbreak at an Edmonton hospital. These isolates were found to contain genes contributing to drug resistance and other potential virulence factors, including a type VI secretion system (T6SS), previously shown to contribute to antibacterial activity between bacteria. These four clinical strains had inactive T6SSs, but when cultured in laboratory settings, a secondary strain emerged which had an active T6SS with all derivatives exhibiting anti-bacterial activity. Through genomic sequencing, we found that T6SS activation correlated with the loss of a number of genes, including many encoding drug resistance and a putative histone-like nucleoid-structuring (HNS) protein, a known regulator of T6SS in A. baumannii. Through detailed complementation experiments, we show that, unlike other A. baumannii strains, this HNS-like protein is not involved in regulation of the T6SS. However, we identify other regulators that may contribute to T6SS repression in these clinical isolates, and hypothesize that a loss of drug resistance may contribute to the environmental survival of this diverse pathogen.

80) Nathan Farrar (Supervisor: Sally Leys) Poster
Abstract title: What Nerveless Sponges tell us about the Origin of Nervous Systems

Sponges are nerveless animals that are phylogenetically situated at the base of the metazoan tree.  Over the last 50 years a small number of studies have suggested that sponges respond to molecules typically associated with neurotransmission.  Using a set of 10 sponge transcriptomes covering each of the four classes we have looked for a range of genes involved in neuronal signaling via synapses.  We find that a large ‘neural toolkit’ exists across the sponges.  A near-complete set of post-synaptic density genes (PSD) is present including ionotropic glutamate receptors previously reported to absent be in sponges.  Though more fragmentary, numerous enzymes involved in neurotransmitter synthesis were also identified.  Axon guidance molecules were also identified through the transcriptome set.  This ‘neural’ repertoire raises interesting questions about its function in sponges, and how these genes may have been coopted into later evolving conventional nervous systems.

81) Jessica Grenke  – Poster
Abstract Title: The Change in Average Rate of Prey Delivery over the Nest Period for Ferruginous Hawks

Ferruginous Hawks (Buteo regalis) are large mixed-grassland predators that are
Provincially Endangered and Federally Threatened. My study objective is to determine how prey delivery rates by Ferruginous Hawks vary over the nesting season. This will allow for a nutritional vulnerability over this period. From 2011 and 2012, digital video cameras were mounted near 96 Ferruginous Hawk nests across the mixed grass ecoregion of Alberta and Saskatchewan. We randomly selected days with video during the nesting season and quantified prey delivery over the 24 hour period, including the time and date of prey items delivered. Average frequency of prey delivery per day was calculated and we examined how rates changed over the nestling period, from approximately ages 10 days to 40 days old. The highest rate of prey delivery occurred from the data beginning to June 10, peaked from June 10 to July 09, then decreasing near the fledge period (July09 to July 26). Our results suggest that juveniles may have been food limited during the


later nestling periods. The period after hatching shows the most vulnerability, while the


fledge phase may be less vulnerable to low prey availability. Our preliminary results can


potentially be used to guide prey supplementation for nestlings during crashes in ground


squirrel population.