INVESTIGATING THE ROLES OF LACTATE DEHYDROGENASES IN THE RICE BLAST FUNGUS MAGNAPORTHE ORYZAE

Magnaporthe oryzae is a filamentous ascomycete fungus that causes rice blast, the most destructive disease of rice worldwide. Upon attachment of pathogen spores to the plant surface, a specialized cell called an appressorium differentiates from the germ tubes to facilitate fungal entry into plant tissues using mechanical force. The appressorium development is fuelled by nutrient reserves carried in spores mainly in the form of lipids and glycogen. Previous studies suggest that breakdown of lipids and glycogen, primarily restricted to the peroxisomes and the cytosol respectively, culminates in production of pyruvate. However, downstream metabolism of pyruvate and its coordination with mitochondrial activities remain elusive. In this study, we showed that D-lactate, interconvertible with pyruvate by activities of lactate dehydrogenases, is a central metabolite utilized during spore germination and appressorium development. Genome-wide analysis of five lactate dehydrogenase genes in M. oryzae demonstrated that a D-lactate dehydrogenase, namely MoDLD1, located on the mitochondrial inner membrane, is responsible for conversion of D-lactate to pyruvate. Targeted replacement of MoDLD1 resulted in failure of efficient appressorium formation, which was associated with inability to utilize lipids and glycogen in fungal spores, and consequently the loss of fungal pathogenicity. In summary, our findings reveal a novel metabolic pathway operated by MoDLD1 that bridges metabolite flow to the mitochondria, and contributes to the fungal development and virulence of M. oryzae

The glycogen synthase kinase MoGsk1, regulated by Mps1 MAP kinase, is required for fungal development and pathogenicity in Magnaporthe oryzae

Magnaporthe oryzae, the causal agent of blast disease, is one of the most destructive plant pathogens, causing significant yield losses on staple crops such as rice and wheat. The fungus infects plants with a specialized cell called an appressorium, whose development is tightly regulated by MAPK signaling pathways following the activation of upstream sensors in response to environmental stimuli. Here, we show the expression of the Glycogen synthase kinase 3 (GSK3) MoGSK1 in M. oryzae is regulated by Mps1 MAP kinase, particularly under the stressed conditions. Thus, MoGSK1 is functionally characterized in this study. MoGsk1 is functionally homologues to the Saccharomyces cerevisiae GSK3 homolog MCK1. Gene replacement of MoGSK1 caused significant delay in mycelial growth, complete loss of conidiation and inability to penetrate the host surface by mycelia-formed appressorium-like structures, consequently resulting in loss of pathogenicity. However, the developmental and pathogenic defects of Delta mogsk1 are recovered via the heterologous expression of Fusarium graminearum GSK3 homolog gene FGK3, whose coding products also shows the similar cytoplasmic localization as MoGsk1 does in M. oryzae. By contrast, overexpression of MoGSK1 produced deformed appressoria in M. oryzae. In summary, our results suggest that MoGsk1, as a highly conservative signal modulator, dictates growth, conidiation and pathogenicity of M. oryzae

Hierarchical Confinement Effect with Zincophilic and Spatial Traps Stabilized Zn-Based Aqueous Battery

Zn-based aqueous batteries (ZABs) have been regarded as promising candidates for safe and large-scale energy storage in the "post-Li" era. However, kinetics and stability problems of Zn capture cannot be concomitantly regulated, especially at high rates and loadings. Herein, a hierarchical confinement strategy is proposed to design zincophilic and spatial traps through a host of porous Co-embedded carbon cages (denoted as CoCC). The zincophilic Co sites act as preferred nucleation sites with low nucleation barriers (within 0.5 mA h cm-2), and the carbon cage can further spatially confine Zn deposition (within 5.0 mA h cm-2). Theoretical simulations and in situ/ex situ structural observations reveal the hierarchical spatial confinement by the elaborated all-in-one network (within 12 mA h cm-2). Consequently, the elaborate strategy enables a dendrite-free behavior with excellent kinetics (low overpotential of ca. 65 mV at a high rate of 20 mA cm-2) and stable cycle life (over 800 cycles), pushing forward the next-generation high-performance ZABs.This research work’s funding was supported by the National Key R&D Program of China (2018YFE0201701 and 2018YFA0209401), National Natural Science Foundation of China (NSFC Grants 52103308 and 22109029), High Impact Project funded by Qatar University (QUHI-CAS-21/22-1), Natural Science Foundation of Jiangsu Province (Grant BK20210826), Natural Science Foundation of Shanghai (22ZR1403600), Fudan University (JIH2203010 and IDH2203008/003), Postdoctoral Science Foundation of China (2021M690658), Talent Development Funding Project of Shanghai (2021030), and Lvyang Jinfeng Plan for Excellent Doctor of Yangzhou City

A solid-to-solid metallic conversion electrochemistry toward 91% zinc utilization for sustainable aqueous batteries

The diffusion-limited aggregation (DLA) of metal ion (Mn+) during the repeated solid-to-liquid (StoL) plating and liquid-to-solid (LtoS) stripping processes intensifies fatal dendrite growth of the metallic anodes. Here, we report a new solid-to-solid (StoS) conversion electrochemistry to inhibit dendrites and improve the utilization ratio of metals. In this StoS strategy, reversible conversion reactions between sparingly soluble carbonates (Zn or Cu) and their corresponding metals have been identified at the electrode/electrolyte interface. Molecular dynamics simulations confirm the superiority of the StoS process with accelerated anion transport, which eliminates the DLA and dendrites in the conventional LtoS/StoL processes. As proof of concept, 2ZnCO3·3Zn(OH)2 exhibits a high zinc utilization of ca. 95.7% in the asymmetry cell and 91.3% in a 2ZnCO3·3Zn(OH)2 || Ni-based full cell with 80% capacity retention over 2000 cycles. Furthermore, the designed 1-Ah pouch cell device can operate stably with 500 cycles, delivering a satisfactory total energy density of 135 Wh kg-1.Published versionThis work was financially supported by the National Natural Science Foundation of China (52102261; 22109029), Natural Science Foundation of Jiangsu Province (BK20210942), Natural Science Foundation of Shanghai (22ZR1403600), Natural Science Foundation of the Jiangsu Higher Education Institutions of China (20KJB150007), and Changzhou Science and Technology Young Talents Promotion Project (KYZ21005). D.C. thanks the financial support from Fudan University (nos. JIH2203010 and IDH2203008/003)

Protocol in evaluating capacity of Zn–Mn aqueous batteries: a clue of pH

In the literature, Zn–Mn aqueous batteries (ZMABs) confront abnormal capacity behavior, such as capacity fluctuation and diverse “unprecedented performances.” Because of the electrolyte additive-induced complexes, various charge/discharge behaviors associated with different mechanisms are being reported. However, the current performance assessment remains unregulated, and only the electrode or the electrolyte is considered. The lack of a comprehensive and impartial performance evaluation protocol for ZMABs hinders forward research and commercialization. Here, a pH clue (proton-coupled reaction) to understand different mechanisms is proposed and the capacity contribution is normalized. Then, a series of performance metrics, including rated capacity (Cr) and electrolyte contribution ratio from Mn2+ (CfM), are systematically discussed based on diverse energy storage mechanisms. The relationship between Mn (II) ↔ Mn (III) ↔ Mn (IV) conversion chemistry and protons consumption/production is well-established. Finally, the concrete design concepts of a tunable H+/Zn2+/Mn2+ storage system for customized application scenarios, opening the door for the next-generation high-safety and reliable energy storage system, are proposed.Ministry of Education (MOE)The authors sincerely acknowledge financial support from the National Natural Science Foundation of China (NSFC grant nos. 21571080, 22109029, and 22279023), Natural Science Foundation of Shanghai (22ZR1403600), International Center of Future Science, Jilin University, Changchun, P. R. China (ICFS Seed Funding for Young Researchers), and the Singapore Ministry of Education by Academic Research Fund Tier 2 (MOE-T2EP50121-0006)

Tandem Chemistry with Janus Mesopores Accelerator for Efficient Aqueous Batteries

A reliable solid electrolyte interphase (SEI) on the metallic Zn anode is imperative for stable Zn-based aqueous batteries. However, the incompatible Zn-ion reduction processes, scilicet simultaneous adsorption (capture) and desolvation (repulsion) of Zn2+(H2O)6, raise kinetics and stability challenges for the design of SEI. Here, we demonstrate a tandem chemistry strategy to decouple and accelerate the concurrent adsorption and desolvation processes of the Zn2+ cluster at the inner Helmholtz layer. An electrochemically assembled perforative mesopore SiO2 interphase with tandem hydrophilic −OH and hydrophobic −F groups serves as a Janus mesopores accelerator to boost a fast and stable Zn2+ reduction reaction. Combining in situ electrochemical digital holography, molecular dynamics simulations, and spectroscopic characterizations reveals that −OH groups capture Zn2+ clusters from the bulk electrolyte and then −F groups repulse coordinated H2O molecules in the solvation shell to achieve the tandem ion reduction process. The resultant symmetric batteries exhibit reversible cycles over 8000 and 2000 h under high current densities of 4 and 10 mA cm–2, respectively. The feasibility of the tandem chemistry is further evidenced in both Zn//VO2 and Zn//I2 batteries, and it might be universal to other aqueous metal-ion batteries