摘要:
Ubiquitination is a fascinating post-translational modification that has received continuous attention since its discovery. In this review, we first provide a concise overview of the E3 ubiquitin ligases, delving into classification, characteristics and mechanisms of ubiquitination. We then specifically examine the ubiquitination pathways mediated by the N/C-degrons, discussing their unique features and substrate recognition mechanisms. Finally, we offer insights into the current state of development pertaining to inhibitors that target the N/C-degron pathways, as well as the promising advances in the field of PROTAC (PROteolysis TArgeting Chimeras). Overall, this review offers a comprehensive understanding of the rapidly-evolving field of ubiquitin biology.
摘要:
The Alon–Tarsi number was defined by Jensen and Toft (Graph coloring problems, Wiley, New York, 1995). The Alon–Tarsi number AT(G) of a graph G is the smallest integer k such that G has an orientation D with maximum outdegree k-1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$k-1$$\end{document} and the number of even circulation is not equal to that of odd circulations in D. It is known that χ(G)≤χl(G)≤AT(G)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\chi (G)\le \chi _l(G)\le AT(G)$$\end{document} for any graph G, where χ(G)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\chi (G)$$\end{document} and χl(G)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\chi _l(G)$$\end{document} are the chromatic number and the list chromatic number of G. Denote by H1□H2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$H_1 \square H_2$$\end{document} and H1⋈H2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$H_1\bowtie H_2$$\end{document} the Cartesian product and the semi-strong product of two graphs H1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$H_1$$\end{document} and H2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$H_2$$\end{document}, respectively. Kaul and Mudrock (Electron J Combin 26(1):P1.3, 2019) proved that AT(C2k+1□Pn)=3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(C_{2k+1}\square P_n)=3$$\end{document}. Li, Shao, Petrov and Gordeev (Eur J Combin 103697, 2023) proved that AT(Cn□C2k)=3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(C_n\square C_{2k})=3$$\end{document} and AT(C2m+1□C2n+1)=4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(C_{2m+1}\square C_{2n+1})=4$$\end{document}. Petrov and Gordeev (Mosc. J. Comb. Number Theory 10(4):271–279, 2022) proved that AT(Kn□C2k)=n\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(K_n\square C_{2k})=n$$\end{document}. Note that the semi-strong product is noncommutative. In this paper, we determine AT(Pm⋈Pn)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(P_m \bowtie P_n)$$\end{document}, AT(Cm⋈C2n)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(C_m \bowtie C_{2n})$$\end{document}, AT(Cm⋈Pn)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(C_m \bowtie P_n)$$\end{document} and AT(Pm⋈Cn)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$AT(P_m \bowtie C_{n})$$\end{document}. We also prove that 5≤AT(Cm⋈C2n+1)≤6\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$5\le AT(C_m \bowtie C_{2n+1})\le 6$$\end{document}.
摘要:
Significance Statement This study has revealed an important role of OsTIL1 in maintaining the cell membrane integrity by regulating the 18:3‐containing glycerolipids biosynthesis and reducing reactive oxygen species damage under cold stress in rice seedlings. SUMMARY Lipocalins constitute a conserved protein family that binds to and transports a variety of lipids while fatty acid desaturases (FADs) are required for maintaining the cell membrane fluidity under cold stress. Nevertheless, it remains unclear whether plant lipocalins promote FADs for the cell membrane integrity under cold stress. Here, we identified the role of OsTIL1 lipocalin in FADs‐mediated glycerolipid remodeling under cold stress. Overexpression and CRISPR/Cas9 mediated gene edition experiments demonstrated that OsTIL1 positively regulated cold stress tolerance by protecting the cell membrane integrity from reactive oxygen species damage and enhancing the activities of peroxidase and ascorbate peroxidase, which was confirmed by combined cold stress with a membrane rigidifier dimethyl sulfoxide or a H2O2 scavenger dimethyl thiourea. OsTIL1 overexpression induced higher 18:3 content, and higher 18:3/18:2 and (18:2 + 18:3)/18:1 ratios than the wild type under cold stress whereas the gene edition mutant showed the opposite. Furthermore, the lipidomic analysis showed that OsTIL1 overexpression led to higher contents of 18:3‐mediated glycerolipids, including galactolipids (monoglactosyldiacylglycerol and digalactosyldiacylglycerol) and phospholipids (phosphatidyl glycerol, phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine and phosphatidyl inositol) under cold stress. RNA‐seq and enzyme linked immunosorbent assay analyses indicated that OsTIL1 overexpression enhanced the transcription and enzyme abundance of four ω‐3 FADs (OsFAD3‐1/3‐2, 7, and 8) under cold stress. These results reveal an important role of OsTIL1 in maintaining the cell membrane integrity from oxidative damage under cold stress, providing a good candidate gene for improving cold tolerance in rice.
期刊:
Journal of Environmental Management,2024年351:119729 ISSN:0301-4797
通讯作者:
Yang, S
作者机构:
[Peng, Kaida; Yang, Shao; Yang, Hongyan; Xu, Min; Cheng, Hu; Liu, Yi; Yang, S; Liu, Pan; Liu, Xiaofeng] Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Peoples R China.
通讯机构:
[Yang, S ] C;Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Peoples R China.
关键词:
Anthropogenic activities;Bloom-forming cyanobacterial genera;Climate change;Driving factors;Sedimentary ancient DNA;Thresholds
摘要:
Cyanobacterial blooms pose a global environmental concern, with various genera contributing to their formation. The harmfulness of cyanobacterial blooms varies depending on the specific genus, yet the factors triggering their formation remain incompletely understood. This study conducted qPCR of sediment DNA in Lake Erhai to reconstruct the historical succession of three common bloom-forming cyanobacterial genera (i.e., Microcystis, Dolichospermum, and Aphanizomenon). The driving factors and their corresponding thresholds were identified, and human activities related to driving factors were evaluated. The results revealed two successions in the past century. The first succession transitioned from Aphanizomenon (1902-1978) to Microcystis and Dolichospermum (1978-1999), driven by TN:TP and TP. The second succession shifted from Microcystis and Dolichospermum (1978-1999) to Microcystis (1999-2010), driven by TP, TN:TP, and temperature. The thresholds of TP and TN:TP for the Microcystis bloom were 0.023mg/L and 17, respectively. TN:TP was significantly influenced by domestic pollution and crop farming in both successions, while TP was significantly impacted by domestic pollution in the first succession and by pollution from crop and dairy farming in the second succession. These results shed light on the underlying mechanism responsible for the blooms of various cyanobacterial genera and could serve as a valuable reference for effectively preventing and controlling nutrient input in the watershed.
作者机构:
[Li, Qian; Yan, Qiang; Yan, Q; Li, Yuntao] Zhejiang Univ, Huzhou Cent Hosp, Affiliated Huzhou Hosp, Dept Gen Surg,Sch Med, Huzhou 313000, Peoples R China.;[Li, Qian; Sun, Yao; Zhao, Fang] Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Ye, Huan] Guangxi Univ, Sch Light Ind & Food Engn, Nanning 530004, Peoples R China.;[Zhang, ZP; Zhang, Zhipeng] Hubei Univ Sci & Technol, Xianning Med Coll, Coll Pharm, Xianning 437100, Peoples R China.
通讯机构:
[Zhang, ZP ] H;[Sun, Y ] C;[Yan, Q ] Z;Zhejiang Univ, Huzhou Cent Hosp, Affiliated Huzhou Hosp, Dept Gen Surg,Sch Med, Huzhou 313000, Peoples R China.;Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
摘要:
Bacterial infections can lead to the development of large-scale outbreaks of diseases that pose a serious threat to human life and health. Also, conventional antibiotics are prone to producing resistance and allergic reactions, and their therapeutic effect is dramatically diminished when bacterial communities form biofilms. Fortunately, well-designed supramolecular coordination complexes (SCCs) have been used as antibacterials or anti-biofilms in recent years. SCCs can kill bacteria by directly engaging with the bacterial surface through electrostatic interactions or by penetrating the bacterial membrane through the auxiliary effect of cell-penetrating peptides. Furthermore, scientists have engineered fluorescent SCCs that can produce reactive oxygen species (ROS) to eliminate bacteria when exposed to laser irradiation, and they also demonstrate outstanding performance in in vivo imaging, enabling integrated diagnosis and treatment. In this review, we summarize the design strategy and applications of SCCs in antibacterials or anti-biofilms and provide an outlook on future research.
摘要:
Immune checkpoint inhibitors (ICIs) therapy targeting programmed cell death ligand 1 (PD-L1) and programmed death protein 1 (PD-1) had exhibited significant clinical benefits for cancer treatment such as triple negative breast cancer (TNBC). However, the relatively low anti-tumor immune response rate and ICIs drug resistance highlight the necessity of developing ICIs combination therapy strategies to improve the anti-tumor effect of immunotherapy. Herein, the immunomodulator epigallocatechin gallate palmitate (PEGCG) and the immunoadjuvant metformin (MET) self-assembled into tumor-targeted micelles via hydrogen bond and electrostatic interaction, which encapsulated the therapeutic agents doxorubicin (DOX)loaded PEGCG-MET micelles (PMD) and combined with ICIs (anti-PD-1 antibody) as therapeutic strategy to reduce the endogenous expression of PD-L1 and improve the tumor immunosuppressive microenvironment. The results presented that PMD integrated chemotherapy and immunotherapy to enhance antitumor efficacy in vitro and in vivo , compared with DOX or anti-PD-1 antibody for the therapy of TNBC. PMD micelles might be a potential candidate, which could remedy the shortcomings of antibody-based ICIs and provide synergistic effect to enhance the antitumor effects of ICIs in tumor therapy.(c) 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.
摘要:
Pyroptosis has garnered significant interest due to its involvement in cancer progression and potential to trigger inflammation and host immune responses. While many efforts have been made to induce pyroptosis using chemotherapeutic agents, these approaches often result in off-target effects, drug resistance, and unwanted systemic toxicity. Furthermore, the non-specific activation of pyroptosis could lead to pro-inflammatory death, creating a microenvironment that potentially heightens the chances of cancer proliferation and metastasis. To solve these limitations, photon-evoking pyroptosis engineering has emerged as a promising approach due to its precise spatiotemporal control, non-invasiveness, and reduced side effects. In this context, this work provides an overview of recent advancements in the molecular mechanisms of pyroptosis, and explore various effective strategies associated with different mode of photon-evoked pyroptosis based on the pyroptosis pathway. Thereafter, we put forth our perspectives on the challenges and prospects of utilizing photon-evoked pyroptosis in anticancer therapy.
期刊:
CHEMISTRY-AN ASIAN JOURNAL,2024年19(2):e202300860- ISSN:1861-4728
通讯作者:
Liu, SH;Hartl, F
作者机构:
[Yang, Xiao Fei; Liu, Sheng Hua; Liu, SH; Zhang, Ming-Xing] Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Zhang, Ming-Xing] Hubei Univ Educ, Coll Chem & Life Sci, Hubei Key Lab Purificat & Applicat Plant Anticanc, Wuhan 430205, Peoples R China.;[Hartl, Frantisek; Hartl, F] Univ Reading, Dept Chem, Reading RG6 6DX, England.
通讯机构:
[Liu, SH ] C;[Hartl, F ] U;Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;Univ Reading, Dept Chem, Reading RG6 6DX, England.
摘要:
The reviewed literature documents that certain metallaaromatics with unconventional photophysical properties, redox and electronic transport properties and magnetism, have potential to be widely used in diverse practical applications, with selected examples of amino acid identification, photothermal effects, functional materials, photodynamic therapy (PDT) in biomedicine, single‐molecule junction conductors, and electron‐transport layer materials (ETLs) in solar cells. Abstract In recent years, the field of organometallic chemistry has made a great progress and diverse types of metallaaromatics have successively been reported. In those studies, incorporation of ligated osmium centers into metallaaromatic systems played a prominent role. The reviewed literature documents that certain metallaaromatics with unconventional photophysical properties, redox and electronic transport properties and magnetism, have potential to be widely used in diverse practical applications, with selected examples of amino acid and fluoride anion identification, photothermal effects, functional materials, photodynamic therapy (PDT) in biomedicine, single‐molecule junction conductors, and electron‐transport layer materials (ETLs) in solar cells.
作者机构:
[Yin, Ya; Chen, Zhao; Deng, Dian-Dian] Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013, People's Republic of China;[Guan, Qichen] State Key Laboratory of Separation Membrane and Membrane Process, School of Chemistry, Tiangong University, Tianjin 300387, People's Republic of China;[Liu, Sheng Hua; Liu, Shanting] Xi'an Key Laboratory of Functional Organic Porous Materials, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an 710129, People's Republic of China;[Sun, Yue] National Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
摘要:
Achieving high-contrast tricolor emissive regulation of a single-component molecule using a single type of external stimulus is highly desirable but challenging. In the present study, we report a symmetric acceptor-donor-acceptor (A-D-A)-type aggregation-induced emission-active luminogen, which displays a sequential high-contrast fluorescence switching just by anisotropic mechanical grinding. Specifically, upon light grinding, an orange-yellow-to-blue hypsochromic mechanofluorochromic response with a distinct color contrast (change in the maximum emission wavelength, Δλ(em,max) = 122 nm) is noticed, and the slightly ground solid exhibits a blue-to-red high-contrast (Δλ(em,max) = 185 nm) bathochromic mechanofluorochromic conversion upon vigorous grinding. Thus, using a single luminogen developed here, we can realize wide-range (Δλ(em,max) > 100 nm) hypso- and bathochromic fluorescence mechanochromisms simultaneously. The tricolored mechanofluorochromic phenomenon is attributed to two different morphological transitions involving crystalline-to-crystalline and crystalline-to-amorphous states. Furthermore, three information anticounterfeiting systems are developed using the luminogen presented here.
摘要:
Particulate matter, represented by soot particles, poses a significant global environmental threat, necessitating efficient control technology. Here, we innovatively designed and elaborately fabricated ordered hierarchical macroporous catalysts of Ce(0.8)Zr(0.2)O(2) (OM CZO) integrated on a catalyzed diesel particulate filter (CDPF) using the self-assembly method. An oxygen-vacancy-enriched ordered macroporous Ce(0.8)Zr(0.2)O(2) catalyst (V(O)-OM CZO) integrated CDPF was synthesized by subsequent NaBH(4) reduction. The V(O)-OM CZO integrated CDPF exhibited a markedly enhanced soot oxidation activity compared to OM CZO and powder CZO coated CDPFs (T(50): 430 vs 490 and 545 °C, respectively). The well-defined OM structure of the V(O)-OM CZO catalysts effectively improves the contact efficiency between soot and the catalysts. Meanwhile, oxygen vacancies trigger the formation of a large amount of highly reactive peroxide species (O(2)(2-)) from molecular oxygen (O(2)) through electron abstraction from the three adjacent Ce(3+) (3Ce(3+) + Vö + O(2) → 3Ce(4+) + O(2)(2-)), contributing to the efficient soot oxidation. This work demonstrates the fabrication of the ordered macroporous CZO integrated CDPF and reveals the importance of structure and surface engineering in soot oxidation, which sheds light on the design of highly efficient PM capture and removal devices.
期刊:
Journal of Carbohydrate Chemistry,2024年 ISSN:0732-8303
通讯作者:
Guo, J
作者机构:
[Zhang, Ru-Yan; Liu, Yan-Ling; Ding, Dong; Guo, J; Wen, Yu; Guo, Jun; Zhou, Shi-Hao; Zou, Yong-Ke] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
通讯机构:
[Guo, J ] C;Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
关键词:
Cancer vaccine;c-GAMP;MUC1;MUC1 glycopeptide;poly(I:C);ternary adjuvant system
摘要:
The highly glycosylated mucin 1 (MUC1) serves as a promising target for cancer vaccines. However, the weak immunogenicity of MUC1 greatly impedes its application. Here, we covalently linked a MUC1 glycopeptide to carrier protein bovine serum albumin (BSA), and the resulting BSA-MUC1 conjugate was integrated with a ternary adjuvant system comprising TLR3 agonist poly(I:C), STING agonist c-GAMP, and Alum adjuvant. Compared to adjuvant-free and Alum-adjuvanted groups, the ternary adjuvant group induced 18.3- and 10.9-fold increases in MUC1-specific IgG titers, and effectively suppressed tumor growth. These findings may propose a straightforward yet highly effective strategy for designing vaccines, offering promising prospects in cancer treatment.
摘要:
Engineering isolated metal sites resembling the primary coordination sphere of metallocofactors enables atomically dispersed materials as promising nanozymes. However, most existing nanozymes primarily focus on replicating specific metallocofactors while neglecting other supporting cofactors within active pockets, leading to reduced electron transfer (ET) efficiency and thus inferior catalytic performances. Herein, we report a metal–organic framework UiO-67 nanozyme with atomically dispersed iron sites, which involves multiple tailored enzyme-like nanocofactors that synergistically drive the ET process for enhanced peroxidase-like catalysis. Among them, the linker-coupled atomic iron site plays a critical role in substrate activation, while bare linkers and zirconia nodes facilitate the ET efficiency of intermediates. The synergy of three nanocofactors results in a 4.29-fold enhancement compared with the single effort of isolated metal site-based nanocofactor, holding promise in immunoassay for sensitive detection of chlorpyrifos. This finding opens a new way for designing high-performance nanozymes by harmonizing various nanocofactors at the atomic and molecular scale.
摘要:
Cancer cells need a greater supply of glucose mainly due to their aerobic glycolysis, known as the Warburg effect. Glucose transport by glucose transporter 1 (GLUT1) is the rate-limiting step for glucose uptake, making it a potential cancer therapeutic target. However, GLUT1 is widely expressed and performs crucial functions in a variety of cells, and its indiscriminate inhibition will cause serious side effects. In this study, we designed and synthesized a photocaged GLUT1 inhibitor WZB117-PPG to suppress the growth of cancer cells in a spatiotemporally controllable manner. WZB117-PPG exhibited remarkable photolysis efficiency and substantial cytotoxicity toward cancer cells under visible light illumination with minimal side effects, ensuring its safety as a potential cancer therapy. Furthermore, our quantitative proteomics data delineated a comprehensive portrait of responses in cancer cells under glucose deprivation, underlining the mechanism of cell death via necrosis rather than apoptosis. We reason that our study provides a potentially reliable cancer treatment strategy and can be used as a spatiotemporally controllable trigger for studying nutrient deprivation-related stress responses.
作者机构:
[Li, Guang; Xu, Weiwei; Hameed, Muhammad Salman; Yang, Qinglin; Li, Haibing; Qu, Haonan] Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Quan, Jiaxin; Quan, JX] Hanjiang Normal Univ, Dept Chem Biol & Environm Engn, Shiyan 442000, Peoples R China.;[Zhang, J; Zhang, Jin] Yunnan Normal Univ, Coll Chem & Chem Engn, Kunming 650092, Peoples R China.;[Sun, Zhongyue] Hubei Univ Chinese Med, Sch Lab Med, Wuhan 430065, Peoples R China.
通讯机构:
[Quan, JX ; Sun, ZY ] H;[Li, HB ] C;[Zhang, J ] Y;Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;Hanjiang Normal Univ, Dept Chem Biol & Environm Engn, Shiyan 442000, Peoples R China.
关键词:
arginine;biomimetic;mimic Cyt C transport;nanochannel;pH
摘要:
Proteins are vital components in cells, biological tissues, and organs, playing a pivotal role in growth and developmental processes in living organisms. Cytochrome C (Cyt C) is a class of heme proteins found in almost all life and is involved in cellular energy metabolic processes such as respiration, mainly as electron carriers or terminal reductases. It binds cardiolipin in the inner mitochondrial membrane, leading to apoptosis. It is a challenge to design a simple and effective artificial system to mimic the complex Cyt C biological transport process. In this paper, an asymmetric biomimetic pH-driven protein gate is described by introducing arginine (Arg) at one end of an hourglass-shaped nanochannel. The nanochannel shows a sensitive protonation-driven protein gate that can be "off" at pH = 7 and "on" at pH = 2. Further studies show that differences in the binding of Arg and Cyt C at different levels of protonation lead to different switching behaviors within the nanochannels, which in turn lead to different surface charges within the nanochannels. It can be used for detecting Cyt C and as an excellent and robust gate for developing integrated circuits and nanoelectronic logic devices.
摘要:
Fosmidomycin (FOS) is a natural product inhibiting the DXR enzyme in the MEP pathway and has stimulated interest for finding more suitable FOS analogues. Herein, two series of FOS analogue hydroxamate-containing bisphosphonates as proherbicides were designed, with bisphosphonate replacing the phosphonic unit in FOS while retaining the hydroxamate (BPF series) or replacing it with retro-hydroxamate (BPRF series). The BPF series were synthesized through a three-step reaction sequence including Michael addition of vinylidenebisphosphonate, N-acylation, and deprotection, and the BPRF series were synthesized with a retro-Claisen condensation incorporated into the reaction sequence. Evaluation on model plants demonstrated several compounds having considerable herbicidal activities, and in particular, compound 8m exhibited multifold activity enhancement as compared to the control FOS. The proherbicide properties were comparatively validated. Furthermore, DXR enzyme assay, dimethylallyl pyrophosphate rescue, and molecular docking verified 8m to be a promising proherbicide candidate targeting the DXR enzyme. In addition, 8m also displayed good antimalarial activities.
作者机构:
[Wang, Dong; Wang, D; Cao, Dandan] Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Hubei, Peoples R China.;[Yang, Yongqing] Chongqing Normal Univ, Coll Life Sci, Chongqing 401331, Peoples R China.;[Wang, Dong; Wang, D] Shaanxi Univ Technol, Bioresources Key Lab Shaanxi Prov, Hanzhong 723001, Shaanxi, Peoples R China.
通讯机构:
[Wang, D ] C;Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Hubei, Peoples R China.;Shaanxi Univ Technol, Bioresources Key Lab Shaanxi Prov, Hanzhong 723001, Shaanxi, Peoples R China.
摘要:
Invasive plants have been shown to alter ecosystem functions. However, there is limited information available on the effect of the invasive species litter input on native litter decomposition and home-field advantage (HFA, increased decomposition at a home environment compared to a guest environment). To investigate this, we conducted a field experiment using leaves of native Trapa natans and Typha orientalis with and without invasive species Alternanthera philoxeroides and then incubated them at T. natans and T. orientalis habitats in a eutrophic lake for 50 days. In control and treatment, the decomposition and N release rate of T. natans were significantly higher than that in T. orientalis species litter at two habitats, indicating no HFA occurrence. A. philoxeroides litter input promoted the decomposition and N decay rate of T. orientalis, not T. natans. The mean decomposition rate of T. orientalis in control and treatment were 0.0138 and 0.0342 day-1; for T. natans, it was 0.0703 and 0.0754 day-1, respectively. The mean N decay rate of T. orientalis in control and treatment were 0.0235 and 0.0468 day-1; for T. natans, it was 0.0511 and 0.0544 day-1, respectively. Invasive species presence increased microbial respiration rate of T. orientalis, but not for T. natans species litter in two habitats. These results suggested that A. philoxeroides litter input accelerated low quality litter decomposition though increased microbial activity. However, it did not influence the HFA performance, which may be closely related to the lake eutrophication.
摘要:
BACKGROUNDS AND AIMS: The hypothesis that plants evolve features that protect accessible pollen from consumption by flower visitors remains poorly understood. METHODS: To explore potential chemical defenses against pollen consumption, we examined the pollinator assemblage, foraging behaviour, visitation frequency and pollen transfer efficiency in Rhododendron molle, a highly toxic shrub containing Rhodojaponin III. Nutrient (protein and lipid) and toxic components in pollen and other tissues were measured. KEY RESULTS: Overall in the five populations, floral visits by butterflies and bumblebees were relatively more frequent than visits by honeybees. All foraged for nectar but not pollen. Butterflies did not differ from bumblebees in the amount of pollen removed per visit, but deposited more pollen per visit. Pollination experiments indicated that R. molle was self-compatible, but both fruit and seed production were pollen limited. Our analysis indicated that the pollen was not protein-poor and had a higher concentration of the toxic compound Rhodojaponin III than petals and leaves, which compound was undetectable in nectar. CONCLUSION: Pollen toxicity in Rhododendron flowers may discourage pollen robbers (bees) from taking the freely accessible pollen grains, while the toxin-free nectar rewards effective pollinators, promoting pollen transfer. This preliminary study supports the hypothesis that chemical defense in pollen would be likely to evolve in species without physical protection from pollinivores.