Chrysin Derivative CM1 and Exhibited Anti-Inflammatory Action by Upregulating Toll-Interacting Protein Expression in Lipopolysaccharide-Stimulated RAW264.7 Macrophage Cells

Although our previous study revealed that gamma-irradiated chrysin enhanced anti-inflammatory activity compared to intact chrysin, it remains unclear whether the chrysin derivative, CM1, produced by gamma irradiation, negatively regulates toll-like receptor (TLR) signaling. In this study, we investigated the molecular basis for the downregulation of TLR4 signal transduction by CM1 in macrophages. We initially determined the appropriate concentration of CM1 and found no cellular toxicity below 2 μg/mL. Upon stimulation with lipopolysaccharide (LPS), CM1 modulated LPS-stimulated inflammatory action by suppressing the release of proinflammatory mediators (cytokines TNF-α and IL-6) and nitric oxide (NO) and downregulated the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways. Furthermore, CM1 markedly elevated the expression of the TLR negative regulator toll-interacting protein (Tollip) in dose- and time-dependent manners. LPS-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II), proinflammatory cytokines (TNF-α and IL-6), COX-2, and iNOS-mediated NO were inhibited by CM1; these effects were prevented by the knockdown of Tollip expression. Additionally, CM1 did not affect the downregulation of LPS-induced expression of MAPKs and NF-κB signaling in Tollip-downregulated cells. These findings provide insight into effective therapeutic intervention of inflammatory disease by increasing the understanding of the negative regulation of TLR signaling induced by CM1.     

In Vitro and In Silico Screening and Characterization of Antimicrobial Napin Bioactive Protein in Brassica juncea and Moringa oleifera

The study aimed to investigate the antibacterial activity of Mustard (Brassica juncea) and Moringa (Moringa oleifera) leaf extracts and coagulant protein for their potential application in water treatment. Bacterial cell aggregation and growth kinetics studies were employed for thirteen bacterial strains with different concentrations of leaf extracts and coagulant protein. Moringa oleifera leaf extract (MOS) and coagulant protein showed cell aggregation against ten bacterial strains, whereas leaf extract alone showed growth inhibition of five bacterial strains for up to 6 h and five bacterial strains for up to 3 h. Brassica juncea leaf extract (BJS) showed growth inhibition for up to 6 h, and three bacterial strains showed inhibition for up to 3 h. The highest inhibition concentration with 2.5 mg/mL was 19 mm, and furthermore, the minimum inhibitory concentration (MIC) (0.5 mg/mL) and MBC (1.5 mg/mL) were determined to have a higher antibacterial effect for <3 KDa peptides. Based on LCMS analysis, napin was identified in both MOS and BJS; furthermore, the mode of action of napin peptide was determined on lipoprotein X complex (LpxC) and four-chained structured binding protein of bacterial type II topoisomerase (4PLB). The docking analysis has exhibited moderate to potent inhibition with a range of dock score −912.9 Kcal/mol. Thus, it possesses antibacterial-coagulant potential bioactive peptides present in the Moringa oleifera purified protein (MOP) and Brassica juncea purified protein (BJP) that could act as an effective antimicrobial agent to replace currently available antibiotics. The result implies that MOP and Brassica juncea purified coagulant (BJP) proteins may perform a wide degree of antibacterial functions against different pathogens.     

Discussion of the protein characterization techniques used in the identification of membrane protein targets corresponding to tumor cell aptamers

Aptamer is an oligonucleotide chain with specific binding ability to protein and other targets,which is widely used in ma ny fields.Because of its ability to screen the premise of unknown targets,it can be used to discover some novel tumor markers,i.e.,membrane proteins that are specifically highly expressed on the surface of tumor cells.Tumor markers can be used in many fields such as early diagnosis and treatment,and a new type of tumor marker proved to be effective can significantly improve the therapeutic effect of such tumors.However,further characterization of newly acquired membrane proteins is essential for their clinical use as tumor markers.This review first briefly introduced the process of obtaining novel tumor markers from nucleic acid aptamers.Next,the commonly used protein characterization methods could be used as a technical means to identify membrane protein targets corresponding to tumor cell aptamers,to clarify the principles,advantages and disadvantages of various means,and to analyze the most suitable situations for various experimental methods.Finally,the outlook was made and the characterization methods that should be used in such experiments were summarized.     

A Water-Soluble Iridium Photocatalyst for Chemical Modification of Dehydroalanines in Peptides and Proteins

Dehydroalanine (Dha) residues are attractive noncanonical amino acids that occur naturally in ribosomally synthesised and post-translationally modified peptides (RiPPs). Dha residues are attractive targets for selective late-stage modification of these complex biomolecules. In this work, we show the selective photocatalytic modification of dehydroalanine residues in the antimicrobial peptide nisin and in the proteins small ubiquitin-like modifier (SUMO) and superfolder green fluorescent protein (sfGFP). For this purpose, a new water-soluble iridium(III) photoredox catalyst was used. The design and synthesis of this new photocatalyst, [Ir(dF(CF₃)ppy)₂(dNMe₃bpy)]Cl₃, is presented. In contrast to commonly used iridium photocatalysts, this complex is highly water soluble and allows peptides and proteins to be modified in water and aqueous solvents under physiologically relevant conditions, with short reaction times and with low reagent and catalyst loadings. This work suggests that photoredox catalysis using this newly designed catalyst is a promising strategy to modify dehydroalanine-containing natural products and thus could have great potential for novel bioconjugation strategies.     

基于分子印迹与表面增强拉曼散射的蛋白质疾病标志物检测研究进展

异常的蛋白质表达与疾病的发生与发展密切相关, 因此蛋白质已作为疾病标志物广泛应用于疾病的早期诊断、治疗监测和预后评估. 然而, 临床样本中的蛋白质疾病标志物通常含量极低, 并存在高丰度的基质干扰, 对检测方法的特异性和灵敏度提出挑战. 目前, 蛋白质疾病标志物的检测方法主要是免疫分析. 但是, 免疫分析主要依赖抗体进行特异性识别, 而抗体具有不易制备、稳定性较差和成本高等缺点. 同时, 免疫分析常通过荧光和化学发光等技术实现高灵敏检测, 但存在操作繁琐、光漂白、光谱宽等不足. 分子印迹聚合物已发展成为在特异性和亲和力方面可媲美抗体的仿生识别材料, 且具有容易制备、稳定性好和成本低等优势. 表面增强拉曼散射技术具有超高灵敏度、光谱窄、快速、无损检测等优势而广泛应用于化学和生物分析. 近年来, 分子印迹技术和表面增强拉曼散射技术的结合产生了系列先进的蛋白质检测方法, 展现了独特的优势, 受到了广泛的关注. 本综述旨在介绍该联用分析技术的主要进展, 在分别介绍分子印迹和表面增强拉曼散射及其在蛋白质检测中单独应用的基础上, 着重介绍基于两种技术的蛋白质疾病标志物的检测方法的研究进展. 最后, 对该联用技术的未来发展做了展望.     

基于二氧化硅胶体晶体薄膜和反射干涉光谱的蛋白冠监测方法

生物分子与纳米材料作用形成的“蛋白冠”影响纳米材料的物理和化学性质, 目前缺少有效的原位实时技术监测蛋白冠的形成过程. 本研究基于二氧化硅胶体晶体薄膜和反射干涉光谱法, 研究了三种代表性血液蛋白质在二氧化硅纳米粒子表面的蛋白冠形成过程, 结果表明这三种蛋白具有不同的蛋白冠形成过程及参数; 研究了人血清白蛋白在三种表面曲率的二氧化硅表面的蛋白冠形成过程, 结果表明曲率越大时, 蛋白冠形成速率越快, 厚度越大. 以血浆和全血样品为生物环境开展蛋白冠形成过程研究, 结果表明本研究的监测方法可以直接用于血浆和全血在纳米粒子表面蛋白冠的形成过程监测, 为纳米材料与生物分子的相互作用研究提供了一种简单可靠的评价技术.     

In Situ Labeling and Distance Measurements of Membrane Proteins in E. coli Using Finland and OX063 Trityl Labels

In situ investigation of membrane proteins is a challenging task. Previously we demonstrated that nitroxide labels combined with pulsed ESR spectroscopy is a promising tool for this purpose. However, the nitroxide labels suffer from poor stability, high background labeling, and low sensitivity. Here we show that Finland (FTAM) and OX063 based labels enable labeling of the cobalamin transporter BtuB and BamA, the central component of the β-barrel assembly machinery (BAM) complex, in E coli. Compared to the methanethiosulfonate spin label (MTSL), trityl labels eliminated the background signals and enabled specific in situ labeling of the proteins with high efficiency. The OX063 labels show a long phase memory time (T_M) of ≈5 μs. All the trityls enabled distance measurements between BtuB and an orthogonally labeled substrate with high selectivity and sensitivity down to a few μm concentration. Our data corroborate the BtuB and BamA conformations in the cellular environment of E. coli.     

Analysis of aging-related protein interactome and cross-network module comparisons across tissues provide new insights into aging

Delaying the human aging process and thus eliminating the risk factors for age-related diseases is one of the prime objectives. While various aging-associated genes and proteins have been characterized, which provide a significant understanding of the human aging process, a significant success in regulating aging is not achieved yet. Understanding how aging proteins interact with each other and also with other proteins could provide important insights into the underlying mechanisms governing the aging process. Therefore, in this work, information of gene expression was included to the static aging-related protein interactome to understand the network-based relationships among aging-related essential (AE) proteins, aging-related non-essential (ANE) proteins, and housekeeping-proteins that could regulate or influence aging. Comprehensive analyses provided various systems-level insights into the regulatory characteristics of aging; for example, (i) network-based correlation analysis predicted functional relationships among AE proteins and ANE proteins; (ii) network variability analysis predicted aging to affect different tissues in strikingly different ways by differentially regulating various regulatory interactions; (iii) cross-network comparisons identified two aging-related modules to be significantly conserved across most of the tissues. Overall, the findings obtained during this study could be helpful for researchers to delay, prevent, or even reverse various aspects of the aging.     

Structural and immunogenicity analysis of reconstructed ancestral and consensus P48/45 for cross-species anti malaria transmission-blocking vaccine

The development of the anti-malaria vaccine holds a promising future in malaria control. One of the anti-malaria vaccine strategies known as the transmission-blocking vaccine (TBV) is to inhibit the parasite transmission between humans and mosquitoes by targeting the parasite gametocyte. Previously, we found that P48/45 included in the 6-Cysteine protein family shared by Plasmodium sp. We also detected vaccine properties possessed by all human-infecting Plasmodium and could be used as a cross-species anti-malaria vaccine. In this study, we investigated the efficacy of P48/45 through the ancestral and consensus reconstruction approach. P48/45 phylogenetic and time tree analysis was done by RAXML and BEAST2. GRASP server and Ugene software were used to reconstruct ancestral and consensus sequences, respectively. The protein structural prediction was made by using a psipred and Rosetta program. Each protein characteristic of P48/45 was analyzed by assessing hydrophobicity and Post-Translational Modification sites. Meanwhile, the Epitope sequence for B-cell, T-cell, and HLA was determined using an immunoinformatics approach. Lastly, molecular docking simulation was done to determine native binding interactions of P48/45-P230. The result showed a distinct protein characteristic of ancestral and consensus sequences. The immunogenicity analysis revealed the number of epitopes in the ancestral sequence is greater than the consensus sequence. The study also found a conserved epitope located in the binding site and consists of specific Post-Translational Modification sites. Hence, our research provides detailed insight into ancestral and consensus P48/45 efficacy for the cross-species anti-malaria vaccine.     

CDFI鉴别男性乳腺良恶性肿瘤价值及与CXCL1、Gab2、MVD的相关性探究

本研究选取18例男性乳腺恶性肿瘤患者作为研究组,纳入同期41例男性良性乳腺肿瘤及50例健康体检男性分别作为良性对照组和健康对照组,通过对比分析发现,研究组CDFI参数[搏动指数(PI)、阻力指数(RI)、血流速度(PSV)]高于良性对照组和健康对照组(P<0.05);PI、RI、PSV联合诊断男性乳腺恶性肿瘤的AUC高达0.854,具有较高应用价值;研究组患者PI、RI、PSV与CXC型趋化因子配体1(CXCL1)、GRB相关蛋白2(Gab2)、微血管密度(MVD)水平间存在正相关关系(P<0.05)。由此可见,CDFI在鉴别男性乳腺良恶性肿瘤方面具有较高应用价值,且与患者CXCL1、Gab2、MVD表达呈正相关。