Highly efficient visible-light photocatalytic ethane oxidation into ethyl hydroperoxide as a radical reservoir

Photocatalytic ethane conversion into value-added chemicals is a great challenge especially under visible light irradiation. The production of ethyl hydroperoxide (CH CH OOH), which is a promising radical reservoir for regulating the oxidative stress in cells, is even more challenging due to its facile decomposition. Here, we demonstrated a design of a highly efficient visible-light-responsive photocatalyst, Au/WO , for ethane oxidation into CH CH OOH, achieving an impressive yield of 1887 μmol g in two hours under visible light irradiation at room temperature for the first time. Furthermore, thermal energy was introduced into the photocatalytic system to increase the driving force for ethane oxidation, enhancing CH CH OOH production by six times to 11 233 μmol g at 100 °C and achieving a significant apparent quantum efficiency of 17.9% at 450 nm. In addition, trapping active species and isotope-labeling reactants revealed the reaction pathway. These findings pave the way for scalable ethane conversion into CH CH OOH as a potential anticancer drug

Interference in transport through double barriers in interacting quantum wires

We investigate interference effects of the backscattering current through a double-barrier structure in an interacting quantum wire attached to noninteracting leads. Depending on the interaction strength and the location of the barriers, the backscattering current exhibits different oscillation and scaling characteristics with the applied voltage in the strong and weak interaction cases. However, in both cases, the oscillation behaviors of the backscattering current are mainly determined by the quantum mechanical interference due to the existence of the double barriers.Comment: 6 pages, 3 fig

Large-scale analyses of heat shock transcription factors and database construction based on whole-genome genes in horticultural and representative plants

Heat shock transcription factor (Hsf) plays a critical role in regulating heat resistance. Here, 2950 Hsf family genes were identified from 111 horticultural and representative plants. More Hsf genes were detected in higher plants than in lower plants. Based on all Hsf genes, we constructed a phylogenetic tree, which indicated that Hsf genes of each branch evolved independently after species differentiation. Furthermore, we uncovered the evolutionary trajectories of Hsf genes by motif analysis. There were only six motifs (M1–M6) in lower plants, and then four novel motifs (M7–M10) appeared in higher plants. However, the motifs of some Hsf genes were lost in higher plants, indicating that Hsf genes have undergone sequence variation during their evolution. The number of Hsf genes lost was greater than the number of genes that were duplicated after whole-genome duplication in higher plants. The heat response network was constructed using 24 Hsf genes and 2421 downstream and 222 upstream genes of Arabidopsis. Further enrichment analysis revealed that Hsf genes and other transcription factors interacted with each other in the response to heat stress. Global expression maps were illustrated for Hsf genes under various abiotic and biotic stresses and several developmental stages in Arabidopsis. Syntenic and phylogenetic analyses were conducted using Hsf genes of Arabidopsis and the pan-genome of 18 Brassica rapa accessions. We also performed expression pattern analysis of Hsf and six Hsp family genes using expression values from different tissues and heat treatments in B. rapa. The interaction network between the Hsf and Hsp gene families was constructed in B. rapa, and several core genes were detected in the network. Finally, we constructed an Hsf database (http://hsfdb.bio2db.com) for researchers to retrieve Hsf gene family information. Therefore, our study will provide rich resources for the study of the evolution and function of Hsf genes

Large-scale analyses of heat shock transcription factors and database construction based on whole-genome genes in horticultural and representative plants

Heat shock transcription factor (Hsf) plays a critical role in regulating heat resistance. Here, 2950 Hsf family genes were identified from 111 horticultural and representative plants. More Hsf genes were detected in higher plants than in lower plants. Based on all Hsf genes, we constructed a phylogenetic tree, which indicated that Hsf genes of each branch evolved independently after species differentiation. Furthermore, we uncovered the evolutionary trajectories of Hsf genes by motif analysis. There were only six motifs (M1–M6) in lower plants, and then four novel motifs (M7–M10) appeared in higher plants. However, the motifs of some Hsf genes were lost in higher plants, indicating that Hsf genes have undergone sequence variation during their evolution. The number of Hsf genes lost was greater than the number of genes that were duplicated after whole-genome duplication in higher plants. The heat response network was constructed using 24 Hsf genes and 2421 downstream and 222 upstream genes of Arabidopsis. Further enrichment analysis revealed that Hsf genes and other transcription factors interacted with each other in the response to heat stress. Global expression maps were illustrated for Hsf genes under various abiotic and biotic stresses and several developmental stages in Arabidopsis. Syntenic and phylogenetic analyses were conducted using Hsf genes of Arabidopsis and the pan-genome of 18 Brassica rapa accessions. We also performed expression pattern analysis of Hsf and six Hsp family genes using expression values from different tissues and heat treatments in B. rapa. The interaction network between the Hsf and Hsp gene families was constructed in B. rapa, and several core genes were detected in the network. Finally, we constructed an Hsf database (http://hsfdb.bio2db.com) for researchers to retrieve Hsf gene family information. Therefore, our study will provide rich resources for the study of the evolution and function of Hsf genes

High-quality ice plant reference genome analysis provides insights into genome evolution and allows exploration of genes involved in the transition from C3 to CAM pathways

Ice plant (Mesembryanthemum crystallinum), a member of the Aizoaceae family, is a typical halophyte crop and a model plant for studying the mechanism of transition from C3 photosynthesis to crassulacean acid metabolism (CAM). Here, we report a high-quality chromosome-level ice plant genome sequence. This 98.05% genome sequence is anchored to nine chromosomes, with a total length of 377.97 Mb and an N50 scaffold of 40.45 Mb. Almost half of the genome (48.04%) is composed of repetitive sequences, and 24 234 genes have been annotated. Subsequent to the ancient whole-genome triplication (WGT) that occurred in eudicots, there has been no recent whole-genome duplication (WGD) or WGT in ice plants. However, we detected a novel WGT event that occurred in the same order in Simmondsia chinensis, which was previously overlooked. Our findings revealed that ice plants have undergone chromosome rearrangements and gene removal during evolution. Combined with transcriptome and comparative genomic data and expression verification, we identified several key genes involved in the CAM pathway and constructed a comprehensive network. As the first genome of the Aizoaceae family to be released, this report will provide a rich data resource for comparative and functional genomic studies of Aizoaceae, especially for studies on salt tolerance and C3-to-CAM transitions to improve crop yield and resistance

Gut microbial DL-endopeptidase alleviates Crohn's disease via the NOD2 pathway

The pattern-recognition receptor NOD2 senses bacterial muropeptides to regulate host immunity and maintain homeostasis. Loss-of-function mutations in NOD2 are associated with Crohn's disease (CD), but how the variations in microbial factors influence NOD2 signaling and host pathology is elusive. We demonstrate that the Firmicutes peptidoglycan remodeling enzyme, DL-endopeptidase, increased the NOD2 ligand level in the gut and impacted colitis outcomes. Metagenomic analyses of global cohorts (n = 857) revealed that DL-endopeptidase gene abundance decreased globally in CD patients and negatively correlated with colitis. Fecal microbiota from CD patients with low DL-endopeptidase activity predisposed mice to colitis. Administering DL-endopeptidase, but not an active site mutant, alleviated colitis via the NOD2 pathway. Therapeutically restoring NOD2 ligands with a DL-endopeptidase-producing Lactobacillus salivarius strain or mifamurtide, a clinical analog of muramyl dipeptide, exerted potent anti-colitis effects. Our study suggests that the depletion of DL-endopeptidase contributes to CD pathogenesis through NOD2 signaling, providing a therapeutically modifiable target