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Abstract Background Phytophthora capsici root rot (PRR) is a disastrous disease in peppers (Capsicum spp.) caused by soilborne oomycete with typical symptoms of necrosis and constriction at the basal stem and consequent plant wilting. Most studies on the QTL mapping of P. capsici resistance suggested a consensus broad-spectrum QTL on chromosome 5 named Pc.5.1 regardless of P. capsici isolates and resistant resources. In addition, all these reports proposed NBS-ARC domain genes as candidate genes controlling resistance. Results We screened out 10 PRR-resistant resources from 160 Capsicum germplasm and inspected the response of locus Pc.5.1 and NBS-ARC genes during P. capsici infection by comparing the root transcriptomes of resistant pepper 305R and susceptible pepper 372S. To dissect the structure of Pc.5.1, we anchored genetic markers onto pepper genomic sequence and made an extended Pc5.1 (Ext-Pc5.1) located at 8.35 Mb–38.13 Mb on chromosome 5 which covered all Pc5.1 reported in publications. A total of 571 NBS-ARC genes were mined from the genome of pepper CM334 and 34 genes were significantly affected by P. capsici infection in either 305R or 372S. Only 5 inducible NBS-ARC genes had LRR domains and none of them was positioned at Ext-Pc5.1. Ext-Pc5.1 did show strong response to P. capsici infection and there were a total of 44 differentially expressed genes (DEGs), but no candidate genes proposed by previous publications was included. Snakin-1 (SN1), a well-known antimicrobial peptide gene located at Pc5.1, was significantly decreased in 372S but not in 305R. Moreover, there was an impressive upregulation of sugar pathway genes in 305R, which was confirmed by metabolite analysis of roots. The biological processes of histone methylation, histone phosphorylation, DNA methylation, and nucleosome assembly were strongly activated in 305R but not in 372S, indicating an epigenetic-related defense mechanism. Conclusions Those NBS-ARC genes that were suggested to contribute to Pc5.1 in previous publications did not show any significant response in P. capsici infection and there were no significant differences of these genes in transcription levels between 305R and 372S. Other pathogen defense-related genes like SN1 might account for Pc5.1. Our study also proposed the important role of sugar and epigenetic regulation in the defense against P. capsici.

In order to further explore the mechanism of ‘sunshine muscat’ grape russet formation, transcriptomic and metabolomic analyses were performed on ‘sunshine muscat’ grape peels with and without russet. A total of 1491 differentially expressed genes (DEGs) were discovered based on these analyses. The phenylpropane synthesis pathway was the key metabolic pathway identified, and 28 DEGs related to phenylpropane synthesis pathway were screened, of which 16 were related to lignin synthesis. In addition, 60 differential metabolites were screened. There were 29 phenolic substances among the differential metabolites, which were all up-regulated and 10 were quercetin-related glycosides. Our results indicate that phenols likely play a dominant role in the formation of ‘sunshine muscat’ grape russet, and the synthesis of lignin and quercetin may be the key factors underlying russet formation.

Unlike many studies that regulate transport and separation behaviour of photogenerated charge carriers through controlling the chemical composite, our work demonstrates this goal can be achieved through simply tuning the molecular π–π packing from short‐range to long‐range within hydrogen‐bonded organic frameworks (HOFs) without altering the building blocks or network topology. Further investigations reveal that the long‐range π–π stacking significantly promotes electron delocalization and enhances electron density, thereby effectively suppressing electron‐hole recombination and augmenting the charge transfer rate. Simultaneously, acting as a porous substrate, it boosts electron density of Pd nanoparticle loaded on its surfaces, resulting in remarkable CO2 photoreduction catalytic activity (CO generation rate: 48.1 μmol/g/h) without the need for hole scavengers. Our study provide insight into regulating the charge carrier behaviours in molecular assemblies based on hydrogen bonds, offering a new clue for efficient photocatalyst design. [ABSTRACT FROM AUTHOR]

Pulang copper deposit is of a super-large porphyry type in the eastern Yidun island arc polymetallic ore belt with frequent tectonic magmatic activities and significant superposition of fissure structure and ore forming-ore controlling conditions. However, the research degree is weak. Based on the comprehensive study of tectonic petrography of tunnels in Pulang copper orefield, combined with the regional metallogenic tectonic setting, the paper determines the macroscopic characteristics of folds and faults, and analyzes the joints/fissures in the typical levels. The results show that the mineralization of porphyry copper deposit during the closure of Paleo-Tethys Ocean is closely related to the Late Triassic tectonic evolution and magmatic activity, with Pulang copper deposit formed in subduction orogeny stage. The regional deep faults control the sedimentary formation and magmatite distribution in the orefield. The deposit is generally occurred in the core of Pulang antiform. The secondary NEE- and NE-trending faults control the development of ore-bearing porphyry and joints/fissures, while the ore/mineralized bodies occur at the junction of two groups of faults. The tension joint-dominated compound joint system provides passage and storage space for ore-bearing hydrothermal fluid migration, diffusion and enrichment. The development degree of fissures is positively correlated with copper mineralization. By studying the characteristics of magmatic intrusion-tectonic fissure system and ore-controlling rule in the orefield, it is considered that the hydrothermal vein ore/mineralized bodies are strictly controlled by the reformation and enrichment of tectonic and fissure system, and the site where fissure structure is well-developed is favorable target for vein ore prospecting. [ABSTRACT FROM AUTHOR]

Parvalbumin (PV) is one of the major allergens in fish. The aim of our present work was to research the influence mechanism of glycation with different reducing sugars (glucose, fructose, ribose, lactose, and galactose) on the immunoglobulin E (IgE) and immunoglobulin G (IgG) binding capacity and structure changes of PV in Alaska Pollock. PV glycated with glucose or fructose (PV‐Glu/ PV‐Fru) exhibited the higher IgE/IgG binding capacities than that of ribose, galactose, or lactose. During glycation, the lysine (Lyr), tyrosine (Tyr), and phenylalanine (Phe) of PV were gradually embed into core area of three‐dimensional structure of protein, which reflected in the ultraviolet (UV) spectrum and fluorescence spectra. Moreover, the increase of surface hydrophobicity had confirmed the conformation alteration of glycated PV. These results suggest that there is a specific association among the change of PV in glycation and in potential allergenicity. The types and conformation of reducing sugar greatly influenced the IgE/IgG binding capacity of PV, and glycation with ribose and galactose was a promising approach for reducing the IgE/IgG binding capacity of PV from Alaska Pollock. Practical applications: Parvalbumin (PV), the major allergen of fish, it can not only maintain the physiological activity of cells, but also cross react with human amyloid protein to alleviate Alzheimer's disease and Parkinson's syndrome. This study revealed that the IgE/IgG binding capacity and structural changes of PV from Alaska Pollock modified by glycation with different reducing sugars. This will help us to understand the sensitization and structural change of the glycated products after the reaction of PV with different reducing sugars. It provides an effective carbonyl source for the preparation of low antigenicity PV based on glycation and lays a foundation for glycation modification of other food allergens. [ABSTRACT FROM AUTHOR]

Nickel catalysts are vulnerable to suffering from carbon deposition and metal sintering in the methane dry reforming process under high temperature. Based on these problems, in this paper, La2O3–KIT-6 materials with different La2O3 contents were designed and prepared in order to take advantage of the basic sites of La2O3 and rich mesoporous structure of KIT-6, and then nickel catalysts supported on La2O3–KIT-6 materials were synthesized. In contrast, the Ni/KIT-6 catalyst was also prepared by the same method. XRD, TEM, SEM, physisorption of N2, XPS, H2-TPR, Raman, and TG were used for fresh and spent catalysts characterization in this work. The catalytic performance of these Ni/La2O3–KIT-6 catalysts was tested under high temperature methane dry reforming reaction. Our work showed that the La2O3-modified catalysts showed reasonably superior catalytic activity and high long term stability compared with the nickel catalyst supported on KIT-6 without modification of La2O3. The high dispersion of nickel nanoparticles on La2O3–KIT-6 as well as the basic property of La2O3 were both helpful to the resistance towards carbon deposition, and the interaction between Ni nanoparticles and support material in Ni/La2O3–KIT-6 was helpful to the resistance towards nickel sintering on account of the special physicochemical properties of La2O3. [ABSTRACT FROM AUTHOR]