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Objective: To study the hypoglycemic effect and mechanism of guar gum manno-oligosaccharides (GMOS) on streptozotocin-induced diabetic mice. Methods: GMOS was administered to diabetic mice for 6 weeks, and the changes in body mass and insulin resistance were monitored. Furthermore, indicators of glucose and lipid metabolism such as glucose (GLU), insulin (INS), high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C) were determined. Hepatic histopathological changes were observed, and the expression of proteins involved in the adenosine monophosphate-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) signaling pathway and the activity of antioxidant enzymes in the liver were detected. Results: GMOS effectively relieved the body mass loss of diabetic mice, significantly alleviated glucose tolerance (30.3%) and enhanced insulin sensitivity (34.6%). Compared with the model group, GMOS decreased the levels of GLU, glycosylated serum protein (GSP) and LDL-C by 38.6%, 29.5%, and 27.3%, respectively, and increased the levels of insulin and HDL-C significantly. Moreover, GMOS reduced oxidative damage, activated the AMPK/PGC-1α signaling pathway, and improved the activities of superoxide dismutase (SOD) and catalase (CAT) in the liver. Conclusion: GMOS could reduce blood glucose and mitigate glucose and lipid metabolism disorder and oxidative stress caused by diabetes mellitus, indicating its potential as a functional food ingredient against diabetes.

Background: The TCP (teosinte branched1/cincinnata/proliferating cell factor) family plays a prominent role in plant development and stress responses. However, TCP family genes have thus far not been identified in castor bean, and therefore an understanding of the expression and functional aspects of castor bean TCP genes is lacking. To identify the potential biological functions of castor bean (RcTCP) TCP members, the composition of RcTCP family members, their basic physicochemical properties, subcellular localizations, interacting proteins, miRNA target sites, and gene expression patterns under stress were assessed. Results: The presence of 20 RcTCP genes on the nine chromosomes of castor bean was identified, all of which possess TCP domains. Phylogenetic analysis indicated a close relationship between RcTCP genes and Arabidopsis AtTCP genes, suggesting potential functional similarity. Subcellular localization experiments confirmed that RcTC01/02/03/10/16/18 are all localized in the nucleus. Protein interaction analysis revealed that the interaction quantity of RcTCP03/06/11 proteins is the highest, indicating a cascade response in the functional genes. Furthermore, it was found that the promoter region of RcTCP genes contains a large number of stress-responsive elements and hormone-induced elements, indicating a potential link between RcTCP genes and stress response functions. qRT-PCR showed that all RcTCP genes exhibit a distinct tissue-specific expression pattern and their expression is induced by abiotic stress (including low temperature, abscisic acid, drought, and high salt). Among them, RcTCP01/03/04/08/09/10/14/15/18/19 genes may be excellent stress-responsive genes. Conclusion: We discovered that RcTCP genes play a crucial role in various activities, including growth and development, the stress response, and transcription. This study provides a basis for studying the function of RcTCP gene in castor. [ABSTRACT FROM AUTHOR]

BACKGROUND: Apolygus lucorum, a major cotton pest, has undergone a significant expansion of the FMRFaR gene within the GPCR superfamily, resulting in two classes of GPCR, namely FMRFaR (A54‐55) and newly duplicated FMRFaR‐like (A56‐62). Notably, FMRFaR‐like genes, particularly A62, show enhanced expression in the legs and wings of adults, indicating their potential role in locomotion. Employing A62 as a representative of FMRFaR‐like, our study investigates the influence of FMRFa, FMRFaR, and FMRFaR‐like on locomotion and development of A. lucorum. RESULTS: FMRFaR and FMRFa exhibit comparable temporal and tissue expression patterns, whereas the FMRFaR‐like genes within A. lucorum exhibit completely distinct evolutionary and expression patterns compared to classical FMRFaR. RNA interference (RNAi) experiments revealed that suppressing FMRFa expression results in complete lethality in A. lucorum, but neither FMRFaR nor A62 exhibit the same effect after RNAi. Suppressing the expression of FMRFa only decreases the expression of the A54 gene simultaneously, suggesting that A54 may function as a classical FMRFaR activated by FMRFa. RNAi of A62 leads to wing malformation and a significant reduction in spontaneous movement behavior in A. lucorum. Further transcriptomic analysis revealed that A62 affects the A. lucorum's movement behavior through energy metabolism pathways and motor protein pathways. CONCLUSION: Our study unveils the unique and complex roles of FMRFa and its receptor in A. lucorum. These findings provide valuable insights into potential targets for pest control strategies aimed at managing A. lucorum populations in cotton fields. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Laminaripentaose (L5)‐producing β‐1,3‐glucanases can preferentially cleave the triple‐helix curdlan into β‐1,3‐glucooligosaccharides, especially L5. In this study, a newly identified member of the glycoside hydrolase family 64, β‐1,3‐glucanase from Streptomyces pratensis (SpGlu64A), was functionally and structurally characterized. SpGlu64A shared highest identity (30%) with a β‐1,3‐glucanase from Streptomyces matensis. The purified SpGlu64A showed maximal activity at pH 7.5 and 50 °C, and exhibited strict substrate specificity toward curdlan (83.1 U·mg−1). It efficiently hydrolyzed curdlan to produce L5 as the end product. The overall structure of SpGlu64A consisted of a barrel domain and a mixed (α/β) domain, which formed an unusually wide groove with a crescent‐like structure. In the two complex structures (SpGlu64A–L3 and SpGlu64A–L4), two oligosaccharide chains were captured and the triple‐helical structure was relatively compatible with the wide groove, which suggested the possibility of binding to the triple‐helical β‐1,3‐glucan. A catalytic framework (β6–β9–β10) and the steric hindrance formed by the side chains of residues Y161, N163, and H393 in the catalytic groove were predicted to complete the exotype‐like cleavage manner. On the basis of the structure, a fusion protein with the CBM56 domain (SpGlu64A–CBM) and a mutant (Y161F; by site‐directed mutation) were obtained, with 1.2‐ and 1.7‐fold increases in specific activity, respectively. Moreover, the combined expression of SpGlu64A–CBM and ‐Y161F improved the enzyme activity by 2.63‐fold. The study will not only be helpful in understanding the reaction mechanism of β‐1,3‐glucanases but will also provide a basis for further enzyme engineering. [ABSTRACT FROM AUTHOR]

The development of environment‐friendly bacteriostats in humid atmosphere is designated as a crucial step pointing to sustainable antibiotic‐free alterative. Thanks to the excellent biosafety and intrinsic bacteriostatic attributes, bioactive phytochemical formulations become a fascinating substitute for traditional antibiotics; yet, it remains a challenge to deliver them toward moisture‐activated bacteriostatic application due to the unclear release mechanism and bacteriostatic behavior. Benefitting from "green" metal–organic frameworks (MOFs) evolved from natural γ‐cyclodextrin (γ‐CD) and potassium ion (K+), an intelligent moisture‐activated phytochemical formulation is developed, which is featured by grafting bacteriostatic vanillin (a specific phytochemical extracted from Rutaceae vanilla bean) into microporous structure of MOFs via ligand implantation mechanism. According to the molecular simulation docking, the dominant pattern of host–guest structure is characteristic for H‐bond with a length of 1.9 Å, beneficial for the sterling adsorption capacity. Nevertheless, under moisture exposure, the intermolecular H‐bond is disrupted for vanillin release to destroy bacterial membrane structure, accelerate protein decomposition, and especially inhibit virulence gene transcription of cfa gene in Escherichia coli and sea gene in Staphylococcus aureus, directing to upgrade the insights into the bacteriostatic potency of phytochemicals in high‐humidity circumstance. [ABSTRACT FROM AUTHOR]

As the field of low‐dimensional materials (1D or 2D) grows and more complex and intriguing structures are continuing to be found, there is an emerging need for techniques to characterize the nanoscale mechanical properties of all kinds of 1D/2D materials, in particular in their most practical state: sitting on an underlying substrate. While traditional nanoindentation techniques cannot accurately determine the transverse Young's modulus at the necessary scale without large indentations depths and effects to and from the substrate, herein an atomic‐force‐microscopy‐based modulated nanomechanical measurement technique with Angstrom‐level resolution (MoNI/ÅI) is presented. This technique enables non‐destructive measurements of the out‐of‐plane elasticity of ultra‐thin materials with resolution sufficient to eliminate any contributions from the substrate. This method is used to elucidate the multi‐layer stiffness dependence of graphene deposited via chemical vapor deposition and discover a peak transverse modulus in two‐layer graphene. While MoNI/ÅI has been used toward great findings in the recent past, here all aspects of the implementation of the technique as well as the unique challenges in performing measurements at such small resolutions are encompassed. [ABSTRACT FROM AUTHOR]

The rapidly expanding severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its variants demand a continuous monitoring method through portable and wearable devices. Utilizing the rich surface chemistry and high chemical‐to‐electrical signal conversion of 2D MXene‐graphene heterostructure thin films, a field‐effect‐transistor (FET) sensor, which has a flexible substrate to be assembled onto the mask and combines with a Bluetooth system for wireless transmission is developed, to detect the influenza and SARS‐CoV‐2 viruses in air and breath. At first, the developed sensors are examined in the laboratory through direct contact with sensing targets in solution form. The results show a low limit of detection (LOD) of 1 fg mL−1 for recombinant SARS‐CoV‐2 spike protein and 125 copies mL−1 for inactivated influenza A (H1N1) virus with high specificity in differing recombinant SARS‐CoV‐2 spike protein and inactivated H1N1 virus. Then the sensors are tested under various simulated human breathing modes through controlled exposure to atomizer‐generated aerosols in an enclosed chamber and mask coverage. The results show the high sensitivity of the developed sensors under varying distances to the source, viral load, flow rate, and enclosed conditions. At last, clinical tests are carried out to demonstrate the robustness and potential field applications of the sensors. [ABSTRACT FROM AUTHOR]

Water resources are indispensable basic resources and important environmental carriers; the presence of organic contaminants in wastewater poses considerable risks to the health of both humans and ecosystems. Although the Fenton-like reactions using H 2 O 2 as the oxidant to destroy organic pollutants are attractive, there are still challenges in improving reaction activity under neutral or even alkaline conditions. Herein, we designed a H 2 O 2 activation pathway with O 2 •- as the main active species and elucidated that the spin interaction between Fe sites and coordinated O atoms effectively promotes the generation of the key intermediate Fe-*OOH. Furthermore, we successfully captured and analyzed the Fe-*OOH intermediate by in situ Raman spectroscopy. When applying FBOB to a continuous-flow reactor, CIP removal efficiency remained at around 90% within 600 min of continuous operation, achieving excellent efficiency, stability, and pH tolerance in removing pollutants., Competing Interests: Competing interests statement:The authors declare no competing interest.