International Journal of Peptide Research and Therapeutics
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2018
·Vol. 25
·期 4
·1319-1331
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IF 1.132
Liu Huifan,Wu Hui,Wang Qin
In a previous study a crude peptide extract was obtained from Dendrobium aphyllum , and this study focused on the functional characterization of the peptide fraction (named DPP) after being purified by DEAE Sepharose. The DPP with high purity contained 16 types of free amino acids and 6 polypeptides. DPP could act as the AAPH-free radical scavenger to protect the erythrocyte under oxidative stress, and the attenuation significantly increased after intestinal digestion. Moreover, the results of the Caco-2 cell models indicated the high absorptive and transfer rates of DPP, in which the passive diffusion was the major transfer pathway. Through the LC-TOF/MS-MS analysis, the peptide sequences Asp-Asp-Asp-Tyr and Asp-Tyr-Asp-Asp were very sensitive to the gastric environment and were completely degraded by Caco-2 cells. While Ser-Ser-Arg, Ala-Val-Thr-Phe , and Met-Leu-Cys-Ala resisted the gastric condition; and sequence Met-Leu-Cys-Ala maintained its structure after the subsequent intestinal digestion and the Caco-2 cells’ uptake.
研究领域:
生物化学
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营养学
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药理学
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DOI
高影响因子
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2020
·Vol. 34
·期 10
·e8736
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IF 2.2
Shutong Yang,Qi Guo,Fangling Wu,Yanqiu Chu,Yuhong Wang,Mingfei Zhou,Chuan-Fan Ding
Rationale The conformation of a protein largely depends on the interactions between peptides. Specific and intrinsic sequence peptide patterns, such as DNA double helix backbones, may be present in proteins. A computational statistical deep learning method has supported this assumption, but it has not been experimentally proven. Mass spectrometry, as a fast and accurate experimental method, could be used to evaluate the interaction of biomolecules. The results would be of great value for further study of the mechanism of protein folding. Methods Several potential intrinsic peptides were chosen by the deep learning method, including seven groups of pentapeptides and five groups of nonapeptides. The noncovalent interactions between mixed polypeptides were investigated by electrospray ionization mass spectrometry (ESI-MS) in full-scan and collision-induced dissociation (CID) modes. Molecular dynamics and molecular mechanics Poisson–Boltzmann surface area (MD-MM/PBSA) analyses were also performed to support the results. Results The ESI-MS spectra showed that 11 of the 12 groups of mixed polypeptides formed binary and ternary complexes with relatively high stability. The binding between nonapeptide groups was stronger than that between pentapeptide groups according to the relative intensity. The binding energies calculated by the MM/PBSA binding energy tool also provided strong evidence for the combination of the complexes. Electrostatic interactions, hydrophobic interactions, and van der Waals forces were thought to stabilize the complexes according to the binding models. Conclusions The results implied the formation of stable complexes between polypeptides and identified their noncovalent interactions, proving that specific sequences and combinations with relatively strong binding ability exist in potential intrinsic sequences of peptides in protein structures.
研究领域:
生物化学
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蛋白质组学
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计算生物学
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DOI
PubMed
高影响因子
ANALYTICAL BIOCHEMISTRY
·
2022
·
IF 3.191
Ruirui Shi,Zhiling Zhao,Guanqun Wang,Wenting Zou,Fengchun Zhao,Zhengyou Yang
Organophosphorus pesticides (OPs) are widely used in agriculture and the monitoring of their residues is very important to protect human health. Immunoassays are important tools for the analysis of small molecules . Generally, noncompetitive mode of immunoassay is considered to be more sensitive than competitive mode. In this study, peptides that can identify immunocomplex of OPs were screened from a phage display library. Subsequently, a second-generation peptide library was constructed and peptides with better performance were isolated. Then, a rapid and sensitive noncompetitive magnetic-phage anti-immunocomplex assay (MPHAIA) for OPs was developed based on the best phage-peptide and single chain antibody immunomagnetic beads. The MPHAIA showed broad specificity for OPs with a thiophosphate group. The half-saturated concentration (SC 50 ) values and limits of detection (LODs) of MPHAIA to 12 OPs were ranged from 15.04 to 105.48 ng/mL and 4.07–14.19 ng/mL, respectively. The accuracy and reliability of MPHAIA were verified by gas chromatography-tandem mass spectrometry (GC-MS/MS) parallel analysis of six kinds of OPs in spiked cucumber samples. The recovery rates were in range of 81.2–116.3% with coefficient of variation from 4.1% to 14.1%, which were consistent with the results of GC-MS/MS.
研究领域:
农业科学
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生物化学
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分析化学
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DOI
PubMed
高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
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2020
·Vol. 246
·期 7
·1483-1494
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IF 2.366
Zhu Jiangxiong,Du Mengke,Wu Meirong,Yue Pengxiang,Yang Xiufang,Wei Xinlin,Wang Yuanfeng
In this study, two novel mixed ACE-inhibiting peptides, namely Se-TAPep 1 and TAPep 1, were prepared and purified from selenium-enriched and common alkali-soluble proteins using a series of process, and then its physicochemical properties and oligopeptide sequence were analyzed. The results showed that Se-TAPep 1 and TAPep 1 could be successfully separated, but their ACE inhibitory activities were different (IC50 values were 13.39 mg/mL and 23.56 mg/mL, respectively), this may be related to the difference in selenium content. Further analysis of physicochemical properties showed that the protein or peptide fractions contained their characteristic absorption peaks and contained aromatic amino acids, while the apparent morphology was different, the presence of selenium could change the apparent morphology of protein or polypeptide fractions, arranging of selenium-enriched fractions more irregular. The amino acid composition analysis showed that the Pro content of the selenium-enriched fractions was higher than that of the ordinary component, whereas the oligopeptide sequence analysis showed that both LQPSLGFP derived from Se-TAPep 1 and AETGEIKGHY derived from TAPep 1 contained some characteristics of highly active ACE-inhibiting peptides, but the characteristics of LQPSLGFP were more conspicuous, which may be related to its molecular weight and source of mixed peptides. These findings indicated that the selenium-enriched tea mixed peptides had better potential uses than ordinary tea mixed peptides in the preparation of functional food.
研究领域:
食品科学
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生物化学
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药理学
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DOI
高影响因子
Chemical Biology & Drug Design
·
2019
·Vol. 94
·期 2
·1494-1503
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IF 2.256
Xi Li,Qingzhu Liu,Siqin Ye,Shijie Wang,Ke Li,Gaochao Lv,Ying Peng,Ling Qiu,Jianguo Lin
Legumain, a lysosomal cysteine protease, is critical for pathological progression and has been found to play an important role in the occurrence and development of several cancers. However, its biological functions remain few recognized. To further understand the role of legumain activity in tumor progression, a legumain protease-responsive fluorescent probe was developed in the present study. The probe 1 was synthesized by conjugating an aminoluciferin fluorophore with an alanine–alanine–asparagine (AAN) peptide sequence. The successful synthesis of probe 1 was validated by NMR and MS spectra as well as HPLC analysis. The probe 1 was non-toxic and exhibited great stability in the physiological solutions. More importantly, compared with the aminoluciferin fluorophore, the peptide conjugation may dramatically increase the targeting specificity. Probe 1 was able to effectively detect the legumain activity in living HCT116 cells through fluorescence imaging. All these results implied that probe 1 could act as a promising fluorescent probe specialized for the monitoring of legumain activity in living cells.
研究领域:
生物化学
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分子生物学
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癌症研究
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细胞生物学
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DOI
PubMed
高影响因子
Advanced Healthcare Materials
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2023
·
IF 10
Xinmiao Lan,Jie Zhong,Regina Huang,Yuhan Liu,Xiaowei Ma,Xuan Li,Dan Zhao,Guangchao Qing,Yuxuan Zhang,Lu Liu,Jinjin Wang,Xu Ma,Ting Luo,Weisheng Guo,Yuji Wang,Li-Li Li,Yu-Xiong Su,Xing-Jie Liang
Antimicrobial peptides (AMPs) are a developing class of natural and synthetic oligopeptides with host defense mechanisms against a broad spectrum of microorganisms, including viruses, bacteria, and fungi. With in-depth research on the structural conformations of AMPs, synthesis or modification of peptides has shown great potential in effectively obtaining new therapeutic agents with improved physicochemical and biological properties. Notably, AMPs with self-assembled properties have gradually become a hot research topic for various materials and biomedical applications. Compared to monomeric peptides, these peptides can exist in diverse forms (e.g., nanoparticles, nanorods, and nanofibers) and possess several advantages, such as high stability, good biocompatibility, and potent biological functions, after forming aggregates under specific conditions. In particular, the stability and antibacterial property of these AMPs can be modulated by rationally regulating the peptide sequences to promote self-assembly, leading to the reconstruction of molecular structure and spatial orientation while introducing some peptide fragments into the scaffolds. In this work, we have developed four self-assembled AMPs, and the relationship between their chemical structures and antibacterial activity were explored extensively through different experiments. Importantly, the evaluation of antibacterial performance in both in vitro and in vivo studies has provided a general guide for using self-assembled AMPs in subsequent treatments for combating bacterial infections. This article is protected by copyright. All rights reserved
研究领域:
生物医学工程
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材料科学
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药学
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微生物学
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产品关联
DOI
PubMed
高影响因子
Nature Microbiology
·
2025
·
IF 19.4
Wang Beilun,Lin Peijun,Zhong Yuwei,Tan Xiao,Shen Yangyang,Huang Yi,Jin Kai,Zhang Yan,Zhan Ying,Shen Dian,Wang Meng,Yu Zhou,Wu Yihan
Artificial intelligence (AI) is a promising approach to identify new antimicrobial compounds in diverse microbial species. Here we developed an AI-based, explainable deep learning model, EvoGradient, that predicts the potency of antimicrobial peptides (AMPs) and virtually modifies peptide sequences to produce more potent AMPs, akin to in silico directed evolution. We applied this model to peptides encoded in low-abundance human oral bacteria, resulting in the virtual evolution of 32 peptides into potent AMPs. Of these, the 6 most effective were synthesized and tested against multidrug-resistant pathogens and demonstrated activity against carbapenem-resistant species Escherichia coli , Klebsiella pneumoniae and Acinetobacter baumannii , and vancomycin-resistant Enterococcus faecium . The most potent AMP, pep-19-mod, was validated in vivo, achieving over 95% reduction in bacterial loads in mouse models of thigh infection through both systemic and local administration. Our approach advances the automatic identification and optimization of AMPs.
研究领域:
人工智能
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微生物学
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药学
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计算生物学
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药物发现
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产品关联
DOI
PubMed
高影响因子
TALANTA
·
2020
·
IF 5.339
Nan Yin,Ruihuan Zhao,Jie Zhang,Dingding Yang,Zhimin Guo,Rui Liu,Xin Yao
Abnormal O-linked N-acetylglucosamine (O-GlcNAc) concentrations have been associated with many diseases, but the lack of accurate detection method limited O-GlcNAc to be used as a biomarker in clinical diagnosis. Then O-GlcNAc transferase (OGT) has drawn researchers’ attention as it closed related to the level of O-GlcNAc and be considered to be a promising new target for diseases diagnosis. Nevertheless, the existing OGT detection methods are either need labeling or the sensitity can not meet the needs of clinic testing. Herein, a label-free and sensitive SPR biosensor was developed for accurate detection of OGT based on a multi-functional peptide. The designed peptide contains three recognition sites, one is the cleavage site of protease K, one is the O-GlcNAcylated site by OGT, and another is six histidine which be used as the signal report probe to recognize Ni 2+ . The immobilized peptide would be cleavaged by proteinase K, then the His-tag residue part will leave the surface of Au film, resulting less His-tag could bind to Ni 2+ and a small SPR signal would be record. If the peptide is O-GlcNAcylated by OGT, the cleaving reaction would be limited due to the adjacent site of O-GlcNAcylation. Then more His-tag can be left on the Au film and a bigger SPR signal could be record, this signal is associated with the concentration of OGT. Utilizing the change of the peptide configuration as a signal report probe for OGT detection not only avoids labeling of peptide, but also makes the method more sensitive. The determination linear range of OGT is from 2.00 × 10 −13 to 5.00 × 10 −8 M with a detection limit of 1.19 × 10 −13 M, and the separation of two enzyme reactions ensured the high selectivity of the method. Finally, the sensing system was successfully used for OGT detection in blood samples with satisfied recovery. In summary, the label-free SPR platform for accurate detection of OGT in real samples is helpful to promote OGT serve as a biomarker for early clinical diagnosis of O-GlcNAc related diseases.
研究领域:
生物化学
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分析化学
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生物传感器
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临床诊断
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产品关联
DOI
PubMed
高影响因子
Food & Function
·
2020
·Vol. 11
·期 6
·5004-5016
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IF 4.171
Kaixin Guo,Linnan Su,Yongchao Wang,Huihui Liu,Jing Lin,Peng Cheng,Xiquan Yin,Ming Liang,Qiangqiang Wang,Zebo Huang
Sea cucumbers have been used as food delicacies and traditional medicine for centuries, and their health benefits are partly attributed to their repertoire of proteins. Peptides prepared from the sea cucumber Apostichopus japonicus are reported to have in vitro antioxidant activities. Here, we investigated the in vivo antioxidant capacity of AjPH, a peptide-rich A. japonicus protein hydrolyzate, and found that AjPH is capable of increasing the survival rate and reducing the reactive oxygen species (ROS) level in the animal model Caenorhabditis elegans under increased oxidative stress induced by paraquat. AjPH is also shown to enhance the antioxidant defense system in paraquat-exposed nematodes, including upregulation of superoxide dismutase and catalase activities and reduction of malondialdehyde contents. To explore underpinning antioxidant mechanisms, cellular and chemical assays were used to demonstrate that AjPH not only reduces ROS accumulation in cells but also directly scavenges DPPH free radicals. Further studies indicate that AjPH can decrease age pigments and extend lifespan but does not reduce food intake, body length and brood size of the nematodes, demonstrating its capacity to delay physiological aging. Using activity-guided fractionation by ultrafiltration and gel filtration, we then isolated antioxidant fractions from AjPH and identified the sequences of their composing peptides, which were subjected to in silico analysis for prospective motifs, physicochemical properties and antioxidant potential. Taken together, our results provide an insight into the nutraceutical potential of the sea cucumber protein hydrolyzate for aging and related conditions and also a basis for future mechanistic studies of individual antioxidant peptides.
研究领域:
营养保健品
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生物化学
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分子生物学
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药理学
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衰老研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）