@article{geng_liu_ji_hoffmann_grunden_xiang_2016, title={Enhancing Heat Tolerance of the Little Dogwood Cornus canadensis L. f. with Introduction of a Superoxide Reductase Gene from the Hyperthermophilic Archaeon Pyrococcus furiosus}, volume={7}, ISSN={1664-462X}, url={http://dx.doi.org/10.3389/fpls.2016.00026}, DOI={10.3389/fpls.2016.00026}, abstractNote={Production of reactive oxygen species (ROS) can be accelerated under various biotic and abiotic stresses causing lipid peroxidation, protein degradation, enzyme inactivation, and DNA damage. Superoxide reductase (SOR) is a novel antioxidant enzyme from Pyrococcus furiosus and is employed by this anaerobic hyperthermophilic archaeon for efficient detoxification of ROS. In this study, SOR was introduced into a flowering plant Cornus canadensis to enhance its heat tolerance and reduce heat induced damage. A fusion construct of the SOR gene and Green Fluorescent Protein gene (GFP) was introduced into C. canadensis using Agrobacterium-mediated transformation. Heat tolerance of the GFP-SOR expressing transgenic plants was investigated by observing morphological symptoms of heat injury and by examining changes in photosynthesis, malondialdehyde (MDA), and proline levels in the plants. Our results indicate that the expression of the P. furiosus SOR gene in the transgenic plants alleviated lipid peroxidation of cell membranes and photoinhibition of PS II, and decreased the accumulation of proline at 40°C. After a series of exposures to increasing temperatures, the SOR transgenic plants remained healthy and green whereas most of the non-transgenic plants dried up and were unable to recover. While it had previously been reported that expression of SOR in Arabidopsis enhanced heat tolerance, this is the first report of the successful demonstration of improved heat tolerance in a non-model plant resulting from the introduction of P. furiosus SOR. The study demonstrates the potential of SOR for crop improvement and that inherent limitations of plant heat tolerance can be ameliorated with P. furiosus SOR.}, journal={Frontiers in Plant Science}, publisher={Frontiers Media SA}, author={Geng, Xing-Min and Liu, Xiang and Ji, Mikyoung and Hoffmann, William A. and Grunden, Amy and Xiang, Qiu-Yun J.}, year={2016}, month={Jan} }
 @article{dalal_yalamanchili_hovary_ji_rodriguez-welsh_aslett_ganapathy_grunden_sederoff_qu_et al._2015, title={A novel gateway-compatible binary vector series (PC-GW) for flexible cloning of multiple genes for genetic transformation of plants}, volume={81}, ISSN={["1095-9890"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84938634755&partnerID=MN8TOARS}, DOI={10.1016/j.plasmid.2015.06.003}, abstractNote={The rapidly advancing field of plant synthetic biology requires transforming plants with multiple genes. This has sparked a growing interest in flexible plant transformation vectors, which can be used for multi-gene transformations. We have developed a novel binary vector series, named the PC-GW series (GenBank: KP826769-KP826773), for Agrobacterium-mediated plant transformation. The PC-GW vectors use the pCAMBIA vector backbone, and contain NPTII, hpt, bar, mCherry or egfp genes as selectable markers for plant transformation. In a modified multiple cloning site (MCS) of the T-DNA region, we have placed the attR1, attR2 and ccdB sequences for rapid cloning of one to four genes by Gateway™-assisted recombination. In addition, we have introduced four meganuclease sites, and other restriction sites for multi-gene vector construction. Finally, we have placed a CaMV 35S promoter and a 35S terminator on the 5' and 3' ends of the MCS. The CaMV 35S promoter is flanked by PstI restriction sites that can be used to replace it with another promoter sequence if needed. The PC-GW vectors provide choices for selectable markers, cloning methods, and can accommodate up to eight gene constructs in a single T-DNA, thereby significantly reducing the number of transformations or crosses needed to generate multi-transgene expressing plants.}, journal={PLASMID}, author={Dalal, J. and Yalamanchili, R. and Hovary, C. La and Ji, M. and Rodriguez-Welsh, M. and Aslett, D. and Ganapathy, S. and Grunden, A. and Sederoff, Heike and Qu, R. D. and et al.}, year={2015}, month={Sep}, pages={55–62} }
 @article{ji_barnwell_grunden_2015, title={Characterization of recombinant glutathione reductase from the psychrophilic Antarctic bacterium Colwellia psychrerythraea}, volume={19}, ISSN={["1433-4909"]}, DOI={10.1007/s00792-015-0762-1}, abstractNote={Glutathione reductases catalyze the reduction of oxidized glutathione (glutathione disulfide, GSSG) using NADPH as the substrate to produce reduced glutathione (GSH), which is an important antioxidant molecule that helps maintain the proper reducing environment of the cell. A recombinant form of glutathione reductase from Colwellia psychrerythraea, a marine psychrophilic bacterium, has been biochemically characterized to determine its molecular and enzymatic properties. C. psychrerythraea glutathione reductase was shown to be a homodimer with a molecular weight of 48.7 kDa using SDS-PAGE, MALDI-TOF mass spectrometry and gel filtration. The C. psychrerythraea glutathione reductase sequence shows significant homology to that of Escherichia coli glutathione reductase (66 % identity), and it possesses the FAD and NADPH binding motifs, as well as absorption spectrum features which are characteristic of flavoenzymes such as glutathione reductase. The psychrophilic C. psychrerythraea glutathione reductase exhibits higher k cat and k cat/K m at lower temperatures (4 °C) compared to mesophilic Baker's yeast glutathione reductase. However, C. psychrerythraea glutathione reductase was able to complement an E. coli glutathione reductase deletion strain in oxidative stress growth assays, demonstrating the functionality of C. psychrerythraea glutathione reductase over a broad temperature range, which suggests its potential utility as an antioxidant enzyme in heterologous systems.}, number={4}, journal={EXTREMOPHILES}, author={Ji, Mikyoung and Barnwell, Callie V. and Grunden, Amy M.}, year={2015}, month={Jul}, pages={863–874} }
 @article{im_ji_lee_killens_grunden_boss_2009, title={Expression of Pyrococcus furiosus Superoxide Reductase in Arabidopsis Enhances Heat Tolerance}, volume={151}, ISSN={["1532-2548"]}, DOI={10.1104/pp.109.145409}, abstractNote={Abstract}, number={2}, journal={PLANT PHYSIOLOGY}, author={Im, Yang Ju and Ji, Mikyoung and Lee, Alice and Killens, Rushyannah and Grunden, Amy M. and Boss, Wendy F.}, year={2009}, month={Oct}, pages={893–904} }
 @article{im_ji_lee_boss_grunden_2005, title={Production of a thermostable archaeal superoxide reductase in plant cells}, volume={579}, ISSN={["1873-3468"]}, DOI={10.1016/j.febslet.2005.09.015}, abstractNote={
Pyrococcus furiosus superoxide reductase (SOR) is a thermostable archaeal enzyme that reduces superoxide without producing oxygen. When produced as a fusion protein with the green fluorescent protein in plant cells, P. furiosus SOR is located in the cytosol and nucleus. The recombinant SOR enzyme retains its function and heat stability when assayed in vitro. Importantly, expressing SOR in plant cells enhances their survival at high temperature indicating that it functions in vivo. The archaeal SOR provides a novel mechanism to reduce superoxide and demonstrates the potential for using archaeal genes to alter eukaryotic metabolism.}, number={25}, journal={FEBS LETTERS}, author={Im, YJ and Ji, MK and Lee, AM and Boss, WF and Grunden, AM}, year={2005}, month={Oct}, pages={5521–5526} }