Biochemistry, Biophysics, and Structural Biology | Open Access Articles

Polar Bears Are Inefficient Predators Of Seabird Eggs, Patrick M. Jagielski, Cody J. Dey, H. Grant Gilchrist, Evan S. Richardson, Oliver P. Love, Christina A.D. Semeniuk

Great Lakes Institute for Environmental Research Publications

Climate-mediated sea-ice loss is disrupting the foraging ecology of polar bears (Ursus maritimus) across much of their range. As a result, there have been increased reports of polar bears foraging on seabird eggs across parts of their range. Given that polar bears have evolved to hunt seals on ice, they may not be efficient predators of seabird eggs. We investigated polar bears' foraging performance on common eider (Somateria mollissima) eggs on Mitivik Island, Nunavut, Canada to test whether bear decision-making heuristics are consistent with expectations of optimal foraging theory. Using aerial-drones, we recorded multiple foraging bouts over 11 days, and …

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A Concise Synthesis Of A Methyl Ester 2-Resorcinarene: A Chair-Conformation Macrocycle, Michael R. Reynolds, Fraser S. Pick, John J. Hayward, John F. Trant

Chemistry and Biochemistry Publications

Anions are important hydrogen bond acceptors in a range of biological, chemical, environ-mental and medical molecular recognition processes. These interactions have been exploited for the design and synthesis of ditopic resorcinarenes as the hydrogen bond strength can be tuned through the modification of the substituent at the 2-position. However, many potentially useful compounds, especially those incorporating electron-withdrawing functionalities, have not been prepared due to the challenge of their synthesis: their incorporation slows resorcinarene formation that is accessed by electrophilic aromatic substitution. As part of our broader campaign to employ resorcinarenes as selective recognition elements, we need access to these specialized …

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A Dft Study Of The Adsorption Of Deep Eutectic Solvents Onto Graphene And Defective Graphene Nanoflakes, Mehdi Shakourian-Fard, S. Maryamdokht Taimoory, Hamid Reza Ghenaatian, Ganesh Kamath, John F. Trant

Chemistry and Biochemistry Publications

The interaction of four deep choline chloride-derived eutectic solvents (DESs) with both graphene nanoflakes (GNF) and its defective double-vacancy and Stone–Wales forms (DV-GNF and SW-GNF), was evaluated using density functional theory (DFT). The presence of defects increases the adsorption energy of DESs, following the order DES∩DV-GNF > DES∩SW-GNF > DES∩GNF. Non-covalent interaction and energy decomposition analyses show that the interactions are noncovalent and dominated by dispersive forces. Furthermore, we find that the presence of aromatic moieties in the DESs increases the van der Waals interactions with the surfaces. These interactions decrease the HOMO-LUMO (Eg) energy gap of the surfaces and thus increase …

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Carbon Dots For Specific “Off-On” Sensing Of Co2+ And Edta For In Vivo Bioimaging, Xiangping Wen, Guangming Wen, Wenyan Li, Zhonghua Zhao, Xine Duan, Wenjun Yan, John F. Trant, Yingqi Li

Chemistry and Biochemistry Publications

Fluorescent carbon dots (CDs) were hydrothermally synthesized from a mixture of frozen tofu, ethylenediamine and phosphoric acid in an efficient 64% yield. The resulting CDs exhibit good water solubility, low cytotoxicity, high stability, and excellent biocompatibility. The CDs selectively and sensitively detect Co2+ through fluorescent quenching with a detection limit of 58 nM. Fluorescence can be restored through the introduction of EDTA, and this phenomenon can be used to quantify EDTA in solution with a detection limit of 98 nM. As both analytes are detected by the same CD platform, this is an “off-on” fluorescence sensor for Co2+ and EDTA. …

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The Biosynthesis Of The Cannabinoids, M. Nazir Tahir, Fred Shahbazi, Simon Rondeau-Gagne, John F. Trant

Chemistry and Biochemistry Publications

Cannabis has been integral to Eurasian civilization for millennia, but a century of prohibition has limited investigation. With spreading legalization, science is pivoting to study the pharmacopeia of the cannabinoids, and a thorough understanding of their biosynthesis is required to engineer strains with specific cannabinoid profiles. This review surveys the biosynthesis and biochemistry of cannabinoids. The pathways and the enzymes’ mechanisms of action are discussed as is the non-enzymatic decarboxylation of the cannabinoic acids. There are still many gaps in our knowledge about the biosynthesis of the cannabinoids, especially for the minor components, and this review highlights the tools and …

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Not-So-Innocent Anions Determine The Mechanism Of Cationic Alkylators, S. Maryamdokht Taimoory, Vincenzo Alessandro Cataldo, Andreas Schäfer, John F. Trant, Ryan Guterman

Chemistry and Biochemistry Publications

Alkylating reagents based on thioimidazolium ionic liquids were synthesized and the influence of the anion on the alkylation reaction mechanism explored in detail using both experimental and computational methods. Thioimidazolium cations transfer alkyl substituents to nucleophiles, however the reaction rate was highly dependent on anion identity, demonstrating that the anion is not innocent in the mechanism. Detailed analysis of the computationally-derived potential energy surfaces associated with possible mechanisms indicated that this dependence arises from a combination of anion induced electronic, steric and coordinating effects, with highly nucleophilic anions catalyzing a 2-step process while highly non-nucleophilic, delocalized anions favor a 1-step …

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Limited Heat Tolerance In An Arctic Passerine: Thermoregulatory Implications For Cold-Specialized Birds In A Rapidly Warming World, Ryan S. O'Connor, Audrey Le Pogam, Kevin G. Young, Francis Robitaille, Emily S. Choy, Oliver P. Love, Kyle H. Elliott, Anna L. Hargreaves, Dominique Berteaux, Andrew Tam, François Vézina

Great Lakes Institute for Environmental Research Publications

Arctic animals inhabit some of the coldest environments on the planet and have evolved physiological mechanisms for minimizing heat loss under extreme cold. However, the Arctic is warming faster than the global average and how well Arctic animals tolerate even moderately high air temperatures (Ta) is unknown. Using flow-through respirometry, we investigated the heat tolerance and evaporative cooling capacity of snow buntings (Plectrophenax nivalis; ≈31 g, N = 42), a cold specialist, Arctic songbird. We exposed buntings to increasing Ta and measured body temperature (Tb), resting metabolic rate (RMR), rates of evaporative water loss (EWL), and evaporative cooling efficiency (the …

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Isolation And Characterization Of Rhizophydiales (Chytridiomycota), Obligate Parasites Of Planktothrix Agardhii In A Laurentian Great Lakes Embayment, Katelyn M. Mckindles, Alejandro N. Jorge, R. Michael Mckay, Timothy W. Davis, George S. Bullerjahna

Great Lakes Institute for Environmental Research Publications

Planktothrix agardhii dominates the cyanobacterial harmful algal bloom community in Sandusky Bay, Lake Erie (USA), from May through September. This filamentous cyanobacterium is host to a known obligate parasite, the chytrid Rhizophydium sp. During the 2018 bloom season, by utilizing dilution and single-filament isolation techniques, 7 chytrid and 12 P. agardhii strains were isolated from Sandusky Bay. These 7 chytrids and a selection of P. agardhii hosts were then characterized with respect to infection rates. Infections by the isolated chytrids were specific to Planktothrix planktonic species and were not found on other filamentous cyanobacterial taxa present in the bay (Aphanizomenon …

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Time-Resolved Sans Reveals Pore-Forming Peptides Cause Rapid Lipid Reorganization, Michael H.L. Nguyen, Mitchell Dipasquale, Brett W. Rickeard, Caesar G. Yip, Kaity N. Greco, Elizabeth G. Kelley, Drew Marquardt

Chemistry and Biochemistry Publications

Cells depend on proper lipid transport and their precise distribution for vital cellular function. Disruption of such lipid organization can be initiated by external agents to cause cell death. Here, we investigate two antimicrobial pore-forming peptides, alamethicin and melittin, and their influence on lipid intervesicular exchange and transverse lipid diffusion (i.e. flip-flop) in model lipid vesicles. Small angle neutron scattering (SANS) and a strategic contrast matching scheme show the mixing of two isotopically distinct dimyristoylphosphocholine (DMPC) vesicle populations is promoted upon the addition of high (1/40) and low (1/150, 1/1000) peptide-to-lipid (P/L) molar ratios. Parsing out the individual exchange and …

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No Common Pesticides Detected In Snow Buntings Utilizing A Farmland Landscape In Eastern Québec, Emily Cornelius Ruhs, Oliver P. Love, Louis Drainville, François Vézina

Great Lakes Institute for Environmental Research Publications

Many species of migratory birds are declining worldwide, including throughout North America. Some of the most cited causes of decline are linked to climate change, urbanization, and growth in agriculture. Across eastern Canada, a number of insecticides and herbicides are commonly sprayed before and during the grain growing season to control pests and foliage competitors. During wintering and migration, a declining Arctic-breeding songbird, the snow bunting (Plectrophenax nivalis), utilizes open farmlands of southern Canada; therefore, this could be a period when the species is most exposed to these pesticides. We tested snow bunting tissues (blood and liver) for the 4 …

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One Hundred Research Questions In Conservation Physiology For Generating Actionable Evidence To Inform Conservation Policy And Practice, Steven J. Cooke, Jordanna N. Bergman, Christine L. Madliger, Rebecca L. Cramp, John Beardall, Gary Burness, Timothy D. Clark, Ben Dantzer, Erick De La Barrera, Nann A. Fangue, Craig E. Franklin, Andrea Fuller, Lucy A. Hawkes, Kevin R. Hultine, Kathleen E. Hunt, Oliver P. Love, Heath A. Macmillan, John W. Mandelman

Great Lakes Institute for Environmental Research Publications

Environmental change and biodiversity loss are but two of the complex challenges facing conservation practitioners and policy makers. Relevant and robust scientific knowledge is critical for providing decision-makers with the actionable evidence needed to inform conservation decisions. In the Anthropocene, science that leads to meaningful improvements in biodiversity conservation, restoration and management is desperately needed. Conservation Physiology has emerged as a discipline that is well-positioned to identify the mechanisms underpinning population declines, predict responses to environmental change and test different in situ and ex situ conservation interventions for diverse taxa and ecosystems. Here we present a consensus list of 10 …

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Researcher Perspectives On Challenges And Opportunities In Conservation Physiology Revealed From An Online Survey, Christine L. Madliger, Oliver P. Love, Vivian M. Nguyen, Neal R. Haddaway, Steven J. Cooke

Great Lakes Institute for Environmental Research Publications

Conservation physiology represents a recently emerging arm of conservation science that applies physiological tools and techniques to understand and solve conservation issues. While a multi-disciplinary toolbox can only help to address the global biodiversity crisis, any field can face challenges while becoming established, particularly highly applied disciplines that require multi-stakeholder involvement. Gaining first-hand knowledge of the challenges that conservation physiologists are facing can help characterize the current state of the field and build a better foundation for determining how it can grow. Through an online survey of 468 scientists working at the intersection of physiology and conservation, we aimed to …

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A Prototype Compact Accelerator-Based Neutron Source (Cans) For Canada, Robert Laxdal, Dalini D. Maharaj, Mina Abbaslou, Zin Tun, Daniel Banks, Alexander Gottberg, Marco Marchetto, Eduardo Rodriguez, Zahra Yamani, Helmut Fritzsche, Ronald Rogge, Ming Pan, Oliver Kester, Drew Marquardt

Chemistry and Biochemistry Publications

Canada's access to neutron beams for neutron scattering was significantly curtailed in 2018 with the closure of the National Research Universal (NRU) reactor in Chalk River, Ontario, Canada. New sources are needed for the long-term; otherwise, access will only become harder as the global supply shrinks. Compact Accelerator-based Neutron Sources (CANS) offer the possibility of an intense source of neutrons with a capital cost significantly lower than spallation sources. In this paper, we propose a CANS for Canada. The proposal is staged with the first stage offering a medium neutron flux, linear accelerator-based approach for neutron scattering that is also …

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The Role Of Conservation Physiology In Mitigating Social-Ecological Traps In Wildlife-Provisioning Tourism: A Case Study Of Feeding Stingrays In The Cayman Islands, Christina A.D. Semeniuk

Great Lakes Institute for Environmental Research Publications

In feeding marine wildlife, tourists can impact animals in ways that are not immediately apparent (i.e. morbidity vs. mortality/reproductive failure). Inventorying the health status of wildlife with physiological indicators can provide crucial information on the immediate status of organisms and long-term consequences. However, because tourists are attempting to maximize their own satisfaction, encouraging the willingness to accept management regulations also requires careful consideration of the human dimensions of the system. Without such socio-ecological measures, the wildlife-tourism system may fall into a trap—a lose–lose situation where the pressure imposed by the social system (tourist expectations) has costs for the ecological system …

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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Polar Bears Are Inefficient Predators Of Seabird Eggs, Patrick M. Jagielski, Cody J. Dey, H. Grant Gilchrist, Evan S. Richardson, Oliver P. Love, Christina A.D. Semeniuk

Great Lakes Institute for Environmental Research Publications

A Concise Synthesis Of A Methyl Ester 2-Resorcinarene: A Chair-Conformation Macrocycle, Michael R. Reynolds, Fraser S. Pick, John J. Hayward, John F. Trant

Chemistry and Biochemistry Publications

A Dft Study Of The Adsorption Of Deep Eutectic Solvents Onto Graphene And Defective Graphene Nanoflakes, Mehdi Shakourian-Fard, S. Maryamdokht Taimoory, Hamid Reza Ghenaatian, Ganesh Kamath, John F. Trant

Chemistry and Biochemistry Publications

Carbon Dots For Specific “Off-On” Sensing Of Co2+ And Edta For In Vivo Bioimaging, Xiangping Wen, Guangming Wen, Wenyan Li, Zhonghua Zhao, Xine Duan, Wenjun Yan, John F. Trant, Yingqi Li

Chemistry and Biochemistry Publications

The Biosynthesis Of The Cannabinoids, M. Nazir Tahir, Fred Shahbazi, Simon Rondeau-Gagne, John F. Trant

Chemistry and Biochemistry Publications

Not-So-Innocent Anions Determine The Mechanism Of Cationic Alkylators, S. Maryamdokht Taimoory, Vincenzo Alessandro Cataldo, Andreas Schäfer, John F. Trant, Ryan Guterman

Chemistry and Biochemistry Publications

Great Lakes Institute for Environmental Research Publications

Isolation And Characterization Of Rhizophydiales (Chytridiomycota), Obligate Parasites Of Planktothrix Agardhii In A Laurentian Great Lakes Embayment, Katelyn M. Mckindles, Alejandro N. Jorge, R. Michael Mckay, Timothy W. Davis, George S. Bullerjahna

Great Lakes Institute for Environmental Research Publications

Time-Resolved Sans Reveals Pore-Forming Peptides Cause Rapid Lipid Reorganization, Michael H.L. Nguyen, Mitchell Dipasquale, Brett W. Rickeard, Caesar G. Yip, Kaity N. Greco, Elizabeth G. Kelley, Drew Marquardt

Chemistry and Biochemistry Publications

No Common Pesticides Detected In Snow Buntings Utilizing A Farmland Landscape In Eastern Québec, Emily Cornelius Ruhs, Oliver P. Love, Louis Drainville, François Vézina

Great Lakes Institute for Environmental Research Publications

Great Lakes Institute for Environmental Research Publications

Researcher Perspectives On Challenges And Opportunities In Conservation Physiology Revealed From An Online Survey, Christine L. Madliger, Oliver P. Love, Vivian M. Nguyen, Neal R. Haddaway, Steven J. Cooke

Great Lakes Institute for Environmental Research Publications

A Prototype Compact Accelerator-Based Neutron Source (Cans) For Canada, Robert Laxdal, Dalini D. Maharaj, Mina Abbaslou, Zin Tun, Daniel Banks, Alexander Gottberg, Marco Marchetto, Eduardo Rodriguez, Zahra Yamani, Helmut Fritzsche, Ronald Rogge, Ming Pan, Oliver Kester, Drew Marquardt

Chemistry and Biochemistry Publications

The Role Of Conservation Physiology In Mitigating Social-Ecological Traps In Wildlife-Provisioning Tourism: A Case Study Of Feeding Stingrays In The Cayman Islands, Christina A.D. Semeniuk

Great Lakes Institute for Environmental Research Publications