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1. Concerted Rolling and Penetration of Peptides during Membrane Binding

   https://doi.org/10.1021/acs.jctc.2c00014  

   Remington, Jacob M.; Ferrell, Jonathon B.; Schneebeli, Severin T.; Li, Jianing (June 2022, Journal of Chemical Theory and Computation)
2. CONCERTED PLANT GROWTH AND DEFENSE THROUGH TARGETED PHYTOHORMONE CROSSTALK MODIFICATION

   https://doi.org/10.1101/2024.04.08.588615  

   Johnston, Grace A; Berry, Hannah M; Kojima, Mikiko; Sakakibara, Hitoshi; Argueso, Cristiana T (April 2024, bioRxiv)

   ABSTRACT Plant immunity activation often results in suppression of plant growth, particularly in the case of constitutive immune activation. We discovered that signaling of the phytohormone cytokinin (CK), known to regulate plant growth through the control of cell division and shoot apical meristem (SAM) activity, can be suppressed by negative crosstalk with the defense phytohormones jasmonic acid (JA), and most evidently, salicylic acid (SA). We show that changing the negative crosstalk of SA on CK signaling in autoimmunity mutants by targeted increase of endogenous CK levels results in plants resistant to pathogens from diverse lifestyles, and relieves suppression of reproductive growth. Moreover, such changes in crosstalk result in a novel reproductive growth phenotype, suggesting a role for defense phytohormones in the SAM, likely through regulation of nitrogen response and cellular redox status. Our data suggest that targeted phytohormone crosstalk engineering can be used to achieve increased reproductive growth and pathogen resistance. SIGNIFICANCE STATEMENTPlants constantly integrate environmental stimuli with developmental programs to optimize their growth and fitness. Excessive activation of the plant immune system often leads to decreased plant growth, a process known as the growth-defense tradeoff. Here, we adapted phytohormone levels in Arabidopsis reproductive tissues of autoimmunity mutants to change phytohormonal crosstalk and diminish the growth tradeoff, resulting in increased broad resistance to pathogens and decreased growth suppression. Similar approaches to phytohormone crosstalk engineering could be used in different contexts to achieve outcomes of higher plant stress resilience and yield. 

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3. Alchemical transformations for concerted hydration free energy estimation with explicit solvation

   https://doi.org/10.1063/5.0036944  

   Khuttan, Sheenam; Azimi, Solmaz; Wu, Joe Z.; Gallicchio, Emilio (February 2021, The Journal of Chemical Physics)
4. Mechanistic Insights into Concerted C–C Reductive Elimination from Homoleptic Uranium Alkyls

   https://doi.org/10.1021/acs.organomet.7b00438  

   Johnson, Sara A.; Higgins, Robert F.; Abu-Omar, Mahdi M.; Shores, Matthew P.; Bart, Suzanne C. (September 2017, Organometallics)
5. Concerted proton–electron transfer reactions of manganese–hydroxo and manganese–oxo complexes

   https://doi.org/10.1039/d0cc01201g  

   Mayfield, Jaycee R.; Grotemeyer, Elizabeth N.; Jackson, Timothy A. (January 2020, Chemical Communications)

   The enzymes manganese superoxide dismutase and manganese lipoxygenase use Mn III –hydroxo centres to mediate proton-coupled electron transfer (PCET) reactions with substrate. As manganese is earth-abundant and inexpensive, manganese catalysts are of interest for synthetic applications. Recent years have seen exciting reports of enantioselective C–H bond oxidation by Mn catalysts supported by aminopyridyl ligands. Such catalysts offer economic and environmentally-friendly alternatives to conventional reagents and catalysts. Mechanistic studies of synthetic catalysts highlight the role of Mn–oxo motifs in attacking substrate C–H bonds, presumably by a concerted proton–electron transfer (CPET) step. (CPET is a sub-class of PCET, where the proton and electron are transferred in the same step.) Knowledge of geometric and electronic influences for CPET reactions of Mn–hydroxo and Mn–oxo adducts enhances our understanding of biological and synthetic manganese centers and informs the design of new catalysts. In this Feature article, we describe kinetic, spectroscopic, and computational studies of Mn III –hydroxo and Mn IV –oxo complexes that provide insight into the basis for the CPET reactivity of these species. Systematic perturbations of the ligand environment around Mn III –hydroxo and Mn IV –oxo motifs permit elucidation of structure–activity relationships. For Mn III –hydroxo centers, electron-deficient ligands enhance oxidative reactivity. However, ligand perturbations have competing consequences, as changes in the Mn III/II potential, which represents the electron-transfer component for CPET, is offset by compensating changes in the p K a of the Mn II –aqua product, which represents the proton-transfer component for CPET. For Mn IV –oxo systems, a multi-state reactivity model inspired the development of significantly more reactive complexes. Weakened equatorial donation to the Mn IV –oxo unit results in large rate enhancements for C–H bond oxidation and oxygen-atom transfer reactions. These results demonstrate that the local coordination environment can be rationally changed to enhance reactivity of Mn III –hydroxo and Mn IV –oxo adducts. 

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