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Publications (317)
Concern about salt levels in freshwater habitats receiving road de-icer runoff has inspired the development of “eco-friendly” formulations that are intended to be less toxic to aquatic organisms, but few experiments have determined that these products are environmentally benign. Mesocosms containing lake water were established for 6 weeks to compar...
At high latitudes, lake whitefish (Coregonus clupeaformis) and others in the closely related Coregonus species complex (CSC) including cisco (C. autumnalis and C. sardinella) can be diadromous, seasonally transitioning between freshwater lakes and the Arctic Ocean. CSC skin- and intestine microbiomes were collected, facilitated by Inuit fishers at...
By preventing freezing, antifreeze proteins (AFPs) can permit cells and organs to be stored at subzero temperatures. As metabolic rates decrease with decreasing temperature, subzero static cold storage (SZ-SCS) could provide more time for tissue matching and potentially lead to fewer discarded organs. Human kidneys are generally stored for under 24...
In the region of King William Island, Nunavut, in the Canadian high Arctic, populations of salmonids including Arctic char (Salvelinus alpinus), cisco (Coregonus autumnalis and C. sardinella) as well as lake whitefish (C. clupeaformis) are diadromous, overwintering in freshwater and transitioning to saline waters following ice melt. Since these fis...
At high latitudes, lake whitefish ( Coregonus clupeaformis ) and others in the closely related Coregonus species complex (CSC), including cisco ( C. autumnalis and C. sardinella ), can be diadromous, seasonally transitioning between freshwater lakes and the Arctic Ocean. CSC skin- and intestine microbiomes were collected, facilitated by Inuit fishe...
The model forage crop, Brachypodium distachyon, has a cluster of ice recrystallization inhibition (BdIRI) genes, which encode antifreeze proteins that function by adsorbing to ice crystals and inhibiting their growth. The genes were targeted for knockdown using a cold-induced promoter from rice (prOsMYB1R35) to drive miRNA. The trans-genic lines sh...
Bacterial ice nucleation proteins (INPs) can cause frost damage to plants by nucleating ice formation at high sub-zero temperatures. Modeling of Pseudomonas borealis INP by AlphaFold suggests that the central domain of 65 tandem sixteen-residue repeats forms a beta-solenoid with arrays of outward-pointing threonines and tyrosines, which may organiz...
Rhizobia are soil-dwelling bacteria that can form N2-fixing symbioses with legume plant species (Fabaceae). These bacteria are globally distributed; however, few studies have examined the genomics of rhizobia that live in cold environments. Here, we isolated and characterized three rhizobial strains from legume nodules collected at a pair of distan...
By preventing freezing, antifreeze proteins (AFPs) can permit cells and organs to be stored at subzero temperatures. As metabolic rates decrease with decreasing temperature, subzero static cold storage (SCS) could provide more time for tissue matching and potentially lead to fewer discarded organs. Human kidneys are generally stored for under 24 h...
Arctic Indigenous Peoples are among the most exposed humans when it comes to foodborne mercury (Hg). In response, Hg monitoring and research have been on-going in the circumpolar Arctic since about 1991; this work has been mainly possible through the involvement of Arctic Indigenous Peoples. The present overview was initially conducted in the conte...
As sugar play a primary role in food flavor and biochemical reaction during the industrial manufacture of dry cured meat products, we aim to evaluate the function of sugar and how the quality changed with the addition of sugar on dry cured sausage after three months of preservation, and the corresponding effect on acidity value and the total acid v...
Antifreeze proteins (AFPs) from the model crop, Brachypodium distachyon, allow freeze survival and attenuate pathogen-mediated ice nucleation. Intriguingly, Brachypodium AFP genes encode two proteins, an autonomous AFP and a leucine-rich repeat (LRR). We present structural models which indicate that ice-binding motifs on the ~13 kDa AFPs can “spoil...
The N2-fixing symbiosis between rhizobia and legumes is negatively impacted by numerous stresses, including low temperatures. To identify genomic features and biochemical pathways of rhizobia that could foster improved symbiotic function under low temperatures, we isolated and characterized three Mesorhizobium strains from legume nodules collected...
The model forage crop, Brachypodium distachyon, has a family of ice recrystallization inhibition (BdIRI) genes, which encode antifreeze proteins that function by adsorbing to ice crystals and inhibiting their growth. The genes were previously targeted for knockdown using a constitutive CaMV 35S promoter and the resulting transgenic Brachypodium sho...
Antifreeze proteins (AFPs) from the model crop, Brachypodium distachyon, allow freeze survival and attenuate pathogen-mediated ice nucleation. Intriguingly, each Brachypodium AFP gene encodes two proteins, an autonomous AFP and a leucine-rich repeat (LRR). We present structural models suggesting that ice-binding motifs on the ~13 kDa AFPs can "spoi...
The model forage crop, Brachypodium distachyon, has a family of ice recrystallization inhibition (BdIRI) genes, which encode antifreeze proteins that function by adsorbing to ice crystals and inhibiting their growth. The genes were previously targeted for knockdown using a constitutive CaMV 35S promoter and the resulting transgenic Brachypodium sho...
Shifts in microbiota undoubtedly support host plants faced with abiotic stress, including low temperatures. Cold-resistant perennials prepare for freeze stress during a period of cold acclimation that can be mimicked by transfer from growing conditions to a reduced photoperiod and a temperature of 4 °C for 2–6 days. After cold acclimation, the mode...
Long-term space missions will expose crew members, their cells as well as their microbiomes to prolonged periods of microgravity and ionizing radiation, environmental stressors for which almost no earth-based organisms have evolved to survive. Despite the importance of maintaining genomic integrity, the impact of these stresses on DNA polymerase-me...
As mercury emissions continue and climate-mediated permafrost thaw increases the burden of this contaminant in northern waters, Inuit from a Northwest passage community in the Canadian Arctic Archipelago pressed for an assessment of their subsistence catches. Sea-run salmonids (n = 537) comprising Arctic char (Salvelinus alpinus), lake trout (S. na...
Low-temperatures pose extreme challenges to crops causing significant economical impacts. Frosts are responsible for more than 30% of weather-related insured crop losses in some temperate climate jurisdictions, but are particularly devastating for small holdings and communities reliant on a bountiful harvest. Low-temperatures are also frequently ac...
In order to survive sub-zero temperatures, some plants undergo cold acclimation where low, non-freezing temperatures and/or shortened day lengths allow cold hardening and survival during subsequent freeze events. Central to this response is the plasma membrane, where low-temperature is perceived and cellular homeostasis must be preserved by maintai...
Two related salmonids, Arctic char (Salvelinus alpinus) and lake whitefish (Coregonus clupeaformis) sampled from the high Arctic region of Nunavut, Canada are anadromous fish, migrating annually from the same ice‐covered freshwater waterbodies to spend summers in the marine waters of the Arctic Ocean. Microbiota associated with the skin‐associated...
In order to survive sub-zero temperatures, some plants undergo cold acclimation where low, non-freezing temperatures and/or shortened day lengths allow cold hardening and survival during subsequent freeze events. Central to this response is the plasma membrane, where low-temperature is perceived and cellular homeostasis must be preserved by maintai...
Recent climate warming in the Arctic is enhancing microbial decomposition of soil organic matter, which may result in globally significant greenhouse gas releases to the atmosphere. To better predict future impacts, bacterial and fungal community structures in both the bulk soil and the rhizosphere of Arctic birch, Betula glandulosa, were determine...
Although intestinal microbial communities from anadromous Arctic char (Salvelinus alpinus (Linnaeus, 1758)) in Kitikmeot, Nunavut, Canada, differ depending on the timing and location of capture, determinants of gut microbiota in other wild Arctic salmonids are largely unknown. Using high-throughput 16S rRNA gene sequence data, we compared intestina...
The identification of food fish bearing anthropogenic contaminants is one of many priorities for Indigenous peoples living in the Arctic. Mercury (Hg), arsenic (As), and persistent organic pollutants including polychlorinated biphenyls (PCBs) are of concern, and these are reported, in some cases for the first time, for fish sampled in and around Ki...
The characterization of ice-binding proteins (IBPs) from plants can involve many techniques, a few of which are presented here. Chief among these methods are tests for ice recrystallization inhibition, an activity characteristic of plant IBPs. Two related procedures are described, both of which can be used to demonstrate and quantify ice-binding ac...
The efficacy of needle-shaped nano-hydroxyapatite (nHA; Ca10(PO4)6(OH)2) as a phosphate (Pi) fertilizer was evaluated as well as its impact on soil and soybean (Glycine max) bacterial and fungal communities. Microbial communities were evaluated in soy fertilized with nHA using ITS (internal transcribed spacer) and 16S rRNA high-throughput gene sequ...
Repeatable experiments with accurate data collection and reproducible analyses are fundamental to the scientific method but may be difficult to achieve in practice. Open‐source tools aid the reproducibility of data analysis, but analogous tools are generally lacking for sample collection and other early stages of scientific inquiry.
We introduce th...
Intestinal microbial communities from 362 anadromous Arctic char (Salvelinus alpinus) from the high Arctic Kitikmeot region, Nunavut, Canada, were characterized using high‐throughput 16S rRNA gene sequencing. The resulting bacterial communities were compared across four seasonal habitats that correspond to different stages of annual migration. Arct...
Knowledge coevolution is the process through which information is generated by joining knowledge systems in an inclusive and iterative way to facilitate self-determination of communities and promote cultural resilience. A central and practical component of this framework is the fostering of progress towards improved co-management and community led...
Fruit flies, Drosophila melanogaster, have been traditionally valued as a simple model system due to their easy and inexpensive culture, their relatively compact genome, and the variety of available genetic tools. However, due to similarities of their neurological and developmental pathways with those of vertebrates, Drosophila also offers advantag...
Northern populations of Arctic char (Salvelinus alpinus) can be anadromous, migrating annually from the ocean to freshwater lakes and rivers in order to escape sub-zero temperatures. Such seasonal behavior demands that these fish and their associated microbiomes adapt to changes in salinity, temperature, and other environmental challenges. We chara...
Repeatable experiments with accurate data collection and reproducible analyses are fundamental to the scientific method but may be difficult to achieve in practice. Several flexible, open-source tools developed for the R and Python coding environments aid the reproducibility of data wrangling and analysis in scientific research. In contrast, analog...
Plants exposed to sub-zero temperatures face unique challenges that threaten their survival. The growth of ice crystals in the extracellular space can cause cellular dehydration, plasma membrane rupture, and eventual cell death. Additionally, some pathogenic bacteria cause tissue damage by initiating ice crystal growth at high sub-zero temperatures...
Sub-zero temperatures put plants at risk of damage associated with the formation of ice crystals in the apoplast. Some freeze-tolerant plants mitigate this risk by expressing ice-binding proteins (IBPs), that adsorb to ice crystals and modify their growth. IBPs are found across several biological kingdoms, with their ice-binding activity and functi...
Life can persist under severe osmotic stress and low water activity in hypersaline environments. On Mars, evidence for the past presence of saline bodies of water is prevalent and resulted in the widespread deposition of sulfate and chloride salts. Here we investigate Spotted Lake (British Columbia, Canada), a hypersaline lake with extreme (>3 M) l...
The action of three distinct recombinant antifreeze proteins (AFPs) as methane hydrate inhibitors was examined using a recently-developed reactor. Compared with traditional approaches, this reactor uses minimal reactant volumes and short experimentation times to assess phase equilibria, kinetics and morphology of a hydrate system in a single experi...
Active layer detachments (ALDs) are permafrost disturbances associated with climate change and increased seasonal warming. Such perturbations result from thawing of the upper permafrost and downslope movement of the overlying thawed material, including the active layer. ALDs have the potential to impact soil microbial community composition and func...
Lolium perenne is a freeze tolerant perennial ryegrass capable of withstanding temperatures below -13 °C. Ice-binding proteins (IBPs) presumably help prevent damage associated with freezing by restricting the growth of ice crystals in the apoplast. We have investigated the expression, localization, and in planta freezing protection capabilities of...
Ice-binding proteins (IBPs) belong to a family of stress-induced proteins that are synthesized by certain organisms exposed to subzero temperatures. In plants, freeze damage occurs when extracellular ice crystals grow, resulting in the rupture of plasma membranes and possible cell death. Adsorption of IBPs to ice crystals restricts further growth b...
Titanium dioxide (TiO2) nanoparticles (NPs) are used as an additive (E171 or INS171) in foods such as gum, candy and puddings. To address concerns about the potential hazardous effects of ingested NPs, the toxicity of these food-grade NPs was investigated with a defined model intestinal bacterial community. Each titania preparation (food-grade TiO2...
Background:
Contemporary kidney preservation methods involve storing at 4 degree C up to 24 h prior to transplantation. By decreasing the storage temperature to below 0 degree C, we hypothesized that the safe storage time could be significantly lengthened.
Objective:
The efficacy of a proprietary CryoStasis (CrS) storage solution for the subzero...
Figure S1 Expression of fluorescently tagged LpIRIP constructs in the roots of transgenic A. thaliana plants. Roots were visualized using a confocal microscope. Experiment was performed in duplicate.
The fate of engineered zero-valent copper nanoparticles (Cu NPs) in soils collected from geographically-distinct regions of the continental United States and incubated under controlled conditions was investigated with respect to NP affinity for soil surfaces and changes in speciation, as well as their impact on bacterial communities. Soil geochemic...
Sub-zero temperatures pose a major threat to the survival of cold-climate perennials. Some of these freeze-tolerant plants produce ice-binding proteins (IBPs) that offer frost protection by restricting ice crystal growth and preventing expansion-induced lysis of the plasma membranes. Despite the extensive in vitro characterization of such proteins,...
Transcript analysis using leaf tissue from non-acclimated wild-type B. distachyon.
Transcripts were amplified for each BdIRI using sequence specific primers (Table 1). SamDC served as a PCR loading reference. Assays were conducted in duplicate with identical results.
(TIF)
Primer sequences utilized for PCR.
The primers used for the generation of the miRBdIRI construct (A) and the forward (FW) and the reverse (RV) primers used for reverse-transcription PCR of BdIRI transcripts (B) are shown. Restriction sites are underlined and melting temperatures (TM) are indicated.
(TIF)
Ice-recrystallization inhibition analysis of recombinant BdIRI isoforms.
A dilution series was conducted on purified BdIRI proteins and ice crystals were observed after annealing at −4°C for 18h. Assay was conducted in triplicate.
(TIF)
Phenotypes of transgenic miRBdIRI plants used in this study.
Twelve-week-old transgenic BdIRI knockdown lines show shorter stature and less above ground biomass compared to wild-type B. distachyon plants.
(TIF)
Prediction of N-linked glycosylation in each BdIRI isoform.
Predictions using BdIRI1-7 sequences were made using the NetNGlyc 1.0 Server with a threshold of 0.5 as a cutoff.
(TIF)
The antimicrobial properties of engineered silver nanoparticles (AgNPs) have led to their wide use in diverse consumer products. Ampicillin too, acts as a broad-spectrum antibiotic and thus is prescribed for the treatment of many common infections, but with the problematic emergence of ampicillin-resistant bacteria. As a consequence, there has been...
Kinetic hydrate inhibitors (KHIs) are used commercially to inhibit gas hydrate form