INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
·
IF 7.7
Chenzhao Wang,Yuhao Jiang,Zhiyu Wu,Xiujuan Wang,Jiawei Yang,Junxian Li,Shanshan Wei,Guoying Sun,Zhibing Wang
Salivary pepsin has emerged as a promising biomarker for rapid screening and diagnosis of gastroesophageal reflux disease (GERD). Pepsin mainly exists in strongly acidic environments and exhibits its highest activity. However, the poor stability of most fluorescent sensors in strong acidic environments brings a significant challenge for pepsin detection. Herein, an innovative biosensor was developed for the highly specific and sensitive detection of pepsin on the basis of green-emitting ionic liquid-based carbon dots (G-IL-CDs) conjugated with whey proteins (WPs). The G-IL-CDs exhibited aggregation-induced fluorescence enhancement when interacting with WP, and the fluorescence intensity decreased after incubation with pepsin due to the disruption of the aggregation structure. This strategy is highly selective for pepsin due to the strongly acidic environment in which other proteases are inactivated. Under optimal experimental conditions, this biosensor successfully detected pepsin in real human saliva with a satisfying recovery. Furthermore, this study not only developed a CDs-based sensor for detecting pepsin but also laid a solid theoretical foundation for the future development of novel biosensors combining CDs and proteins.
研究领域:
生物技术
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分析化学
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医学诊断
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DOI
PubMed
高影响因子
Marine Drugs
·
2018
·Vol. 16
·期 1
·29
·
IF 4.379
Fangmiao Yu,Chuhong Zong,Shujie Jin,Jiawen Zheng,Nan Chen,Ju Huang,Yan Chen,Fangfang Huang,Zuisu Yang,Yunping Tang,Guofang Ding
In the present study, response surface methodology was performed to investigate the effects of extraction parameters on pepsin-solubilised collagen (PSC) from the skin of the giant croakerNibea japonica. The optimum extraction conditions of PSC were as follows: concentration of pepsin was 1389 U/g, solid-liquid ratio was 1:57 and hydrolysis time was 8.67 h. Under these conditions, the extraction yield of PSC was up to 84.85%, which is well agreement with the predict value of 85.03%. The PSC fromNibea japonicaskin was then characterized as type I collagen by using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The fourier transforms infrared spetroscopy (FTIR) analysis revealed that PSC maintains its triple-helical structure by the hydrogen bond. All PSCs were soluble in the pH range of 1.0–4.0 and decreases in solubility were observed at neutral or alkaline conditions. All PSCs had a decrease in solubility in the presence of sodium chloride, especially with a concentration above 2%. So, theNibea japonicaskin could serve as another potential source of collagen.Keywords:marine collagen;Nibea japonica;response surface methodology;optimization;characterization
研究领域:
海洋生物学
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食品科学
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生物化学
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DOI
PubMed
高影响因子
Nano Today
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2020
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IF 16.907
Xinqi Cai,Yiting Xu,Lina Zhao,Jiamei Xu,Shengkai Li,Chaoqi Wen,Xin Xia,Qian Dong,Xiaoxiao Hu,Xiaofeng Wang,Long Chen,Zhuo Chen,Weihong Tan
Gastric environment is an extreme pH and enzyme-rich condition, which together with gastric mucus barrier and short retention time of oral medicine militate against effective oral drug delivery to lesion areas of gastric diseases. Assembly, especially shape-control assembly of magnetic nanoparticles potentially helps the site-selective drug molecule delivery. However, the harsh gastric condition, and cumbersome and strict requirements make the in situ reversible assembly remain challenging. Herein, synergistically pepsin-bridged and magnetic field-mediated morphological control of magnetic-graphitic-nanocapsules (MGNs) needle assembly (MNA) is developed in stomach for prolonged gastric retention and enhanced mucus penetration. The MNAs with good biocompatibility, large magnetic moments and unique needle-shape are formed with the help of pepsin , demonstrating superior magnetic-driven capability to overcome gastric mucus barrier. Molecular dynamics simulations reveal binding modes between MGN and amino acid residues on either side of the pepsin, indicating pepsin acts as “bridge” allowing sufficient contact among MGNs and further facilitates the needle assembly. Moreover, anticancer drug doxorubicin (DOX)-loaded MNAs demonstrate superior targeted cancer cell killing ability and boosted DOX penetration in a mouse model, which promises good bioavailability of drug molecules. The versatile MNA-based platform offers a robust strategy for effective oral drug delivery and site-selective therapy of gastric diseases.
研究领域:
药学
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纳米技术
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生物医学工程
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药物递送系统
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DOI
高影响因子
JOURNAL OF MOLECULAR RECOGNITION
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2016
·Vol. 29
·期 10
·476-484
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IF 2.091
Hua-jin Zeng,Dan Yang,Gui-zhou Hu,Ran Yang,Ling-bo Qu
In this study, the molecular interactions between pepsin and three pyrethroid insecticides, including fenvalerate, cyhalothrin and deltamethrin, were investigated by multi-spectroscopic and molecular docking methods under mimic physiological pH conditions. The results indicated that all of these insecticides could interact with pepsin to form insecticide–pepsin complexes. The binding constants, number of binding sites and thermodynamic parameters measured at different temperatures indicated that these three pyrethroid insecticides could spontaneously bind with pepsin mainly through electrostatic forces and hydrophobic interactions with one binding site. According to the theory of Föster's non-radioactive energy transfer, the distance ( r ) between pepsin and three pyrethroid insecticides were all found to be less than 7 nm, which implied that the energy transfer occurred between pepsin and these insecticides, leading to the quenching of pepsin fluorescence. Synchronous and three-dimensional fluorescence, CD spectra and molecular docking results indicated that all tested pyrethroid insecticides bound directly into the enzyme cavity site and the binding of insecticides into the cavity influenced the microenvironment of the pepsin activity site which resulted in the extension of peptide strands of pepsin with loss of α-helix structures.Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
生物化学
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环境科学
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分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2013
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IF 2.906
Yan-Qing Wang,Hong-Mei Zhang
To explore the binding mechanism of phthalate plasticizers with digestive proteases, their effects on conformation and activity of pepsin by multispectroscopic approach and molecular modeling were investigated. Fluorescence spectra combined with UV–vis and circular dichroism (CD) spectra measurements indicated that the six phthalate plasticizers induced the changes of tertiary and secondary structure of pepsin. The solvent polarity of environment around both Trp and Tyr residues on pepsin were affected by phthalate plasticizers. By analyzing the fluorescence quenching and theoretical calculation data, it was concluded that a binding site exists for each phthalate plasticizer in pepsin with different binding ability. The hydrophobic, hydrogen bonding, and π–π stacking interactions were involved in the interactions between pepsin and phthalate plasticizers. Moreover, the activity assay indicated that phthalate plasticizers were not powerfully inhibitors or activators for pepsin. These studies demonstrated that phthalate plasticizers could cause some negative effects on pepsin. The present studies may provide a way to analyze the biological safety of phthalate plasticizers on digestive proteases or other proteins.
研究领域:
生物化学
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环境科学
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毒理学
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DOI
PubMed
高影响因子
Food Bioscience
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2019
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IF 3.22
Chun-Min Ma,Tie-Jing Li,Xin-Huai Zhao
Lactoferrin hydrolysates (LF-H) were digested using pepsin and modified using a pepsin-catalyzed plastein reaction with tryptophan (Trp) to obtain a target product. LF-H, the target product, plastein reaction-modified LF-H alone, and a mixture of LF-H and Trp were evaluated for their activities with human gastric cancer BGC-823 cells at 24 and 48 h. Assay results indicated that the target product had decreased free amino groups and had incorporated Trp. LF-H and the plastein reaction-modified LF-H alone did not show detectable growth inhibition on BGC-823 cells at 1–3 mg/mL; however, the target product at the same dose levels inhibited cell growth, and showed higher activity than the mixture ( P < 0.05). The target product at 2 and 3 mg/mL stopped cell cycle progression at the G0/G1-phase, induced DNA fragmentation , and showed apoptosis induction, which increased the number of apoptotic cells. Moreover, time- and dose-dependent responses were observed in these experiments. RT-PCR assay results indicated that exposure of the cells to the target product resulted in up- and down-regulated mRNA expression for 7 apoptosis-related genes, namely Bcl-2, Bcl-xl, Bad, Bax, caspase-3, caspase-6, and caspase-9. Thus, the plastein reaction increased in vitr o anticancer activities of LF-H with BGC-823 cells, and more importantly, both the plastein reaction and Trp incorporation contributed to enhanced activities.
研究领域:
生物化学
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癌症研究
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分子生物学
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DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2022
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IF 4.831
Jinying Guo,Chuanfa Gan,Bo Cheng,Bo Cui,Fankai Yi
Pepsin plays an important role in nutrient metabolism. Apigenin (AP) is a beneficial polyphenol to human health. To enhance the bioavailability of AP and elucidate the inhibitory effect of AP on pepsin, the interaction mechanism of AP with pepsin was investigated using spectroscopic analysis and molecular docking, and the activity of pepsin and antioxidant activity of AP was also evaluated. Specifically, AP performed static quenching of pepsin and had only one binding site on pepsin. More interestingly, the interaction between AP and pepsin was spontaneous, while hydrogen bonds and van der Waals forces were the main binding forces. Generally, synchronous and three-dimensional fluorescence confirmed that AP induced the conformational changes of pepsin, and molecular docking proved the above results and illustrated the specific binding patterns. Specifically, AP inhibited the activity of pepsin, while pepsin decreased the antioxidant activity of AP. These results provided useful information for elucidating the interactions between AP and pepsin.
研究领域:
生物化学
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营养学
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药物化学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2023
·
IF 8.8
Jie Zhao,Shuaiqian Wang,Diandian Jiang,Chong Chen,Jie Tang,Igor Tomasevic,Weizheng Sun
The stability behaviors of oxidized SPI emulsions under in vitro gastric conditions and the effects of pepsin diffusion on the proteolysis of emulsions were investigated using a static gastric model and the fluorescence recovery after photobleaching method. Results showed that protein oxidation increased the particle size of droplets and decreased the viscoelasticity of the interfacial layer. Compared to the control group (82.81 m 2 /s), the pepsin diffusivity decreased to 68.52 m 2 /s (7LA + LOX group) due to the space hindrance of oil droplets. After gastric digestion, protein hydrolysates were re-absorbed on the oil–water interface and formed a thick layer, thereby decreasing the size of oil droplets and reducing the contents of free amino acids in gastric digesta. The protein oxidation may affect the adsorption of interfacial proteins and alter the distribution of droplets, decreasing pepsin diffusion and ultimately impairing the emulsion gastric digestion. And this should be considered in the design of emulsion as the controllable delivery system.
研究领域:
食品科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Shengnan Hu,Hanzhu Kong,Yuting Sun,Ronghui Wu,Jing Xu,Ming Guo
Biological enzyme-driven degradation of environmental pollutants has attracted widespread attention because it is ecofriendly and highly efficient. Immobilized enzyme technology has emerged as a promising technique in enzymology that addresses the limitations associated with free enzymes. Traditional solid-loaded enzyme substrates are often affected by blockages and restricted substrate accessibility. In this study, we synthesized an efficient heterogeneous pepsin catalyst, named PEP@M-MIL100(Fe), by covalently combining carboxylated ferrite structural expanded metal–organic frameworks with pepsin. This catalyst demonstrated excellent environmental adaptability and remarkable catalytic degradation capabilities. Notably, it rapidly degraded the persistent microplastic pollutant diisononyl phthalate (DINP) within just 150 min, with a removal efficiency of up to 95.88%. Impressively, even after 10 consecutive uses, the catalyst maintained its high performance. We proposed an innovative steady-state heterogeneous enzyme-catalyzed degradation mechanism, i.e., diffusion (D)–absorption (A)–binding (B)–reaction (R)–degradation (D)–link mechanism, which emphasizes the influence of substrate diffusion rates in this process. This work presents the first successful application of pepsin to DINP degradation and offers a sustainable and effective approach for addressing contemporary pollution challenges.
研究领域:
环境科学
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酶学
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材料科学
·
污染控制
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Min Hu,Jia-Xu Song,Shi-Tao Miao,Cheng-Kai Wu,Xing-Wen Gong,Hong-Ju Sun
Acetaldehyde dehydrogenase 2 (ALDH2) is a crucial enzyme in alcohol metabolism, and oral administration of ALDH2 is a promising method for alcohol detoxification. However, recombinant ALDH2 is susceptible to hydrolysis by digestive enzymes in the gastrointestinal tract and is expressed as inactive inclusion bodies in E. coli . In this study, we performed three rounds of rational design to address these issues. Specifically, the surface digestive sites of pepsin and trypsin were replaced with other polar amino acids, while hydrophobic amino acids were incorporated to reshape the catalytic cavity of ALDH2. The resulting mutant DE2–852 exhibited a 45-fold increase in soluble expression levels, while its stability against trypsin and pepsin increased by eightfold and twofold, respectively. Its catalytic efficiency ( k cat /K m ) at pH 7.2 and 3.2 improved by more than four and five times, respectively, with increased V max and decreased K m values. The enhanced properties of DE2–852 were attributed to the D457Y mutation, which created a more compact protein structure and facilitated a faster collision between the substrate and catalytic residues. These results laid the foundation for the oral administration and mass preparation of highly active ALDH2 and offered insights into the oral application of other proteins.
研究领域:
生物化学
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蛋白质工程
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药物开发
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2023
·
IF 8.8
Chunli Lei,Mengna Tao,Lanqing Xu,Le Yue,Xuesong Cao,Bingxu Cheng,Chuanxi Wang,Zhenyu Wang
Application of nanomaterials (NMs) in agriculture poses an ingestion risk to humans and may affect the digestive process. Different fates of NMs with differential charges in the gastrointestinal tract should be considered. In this study, the interaction between three carbon dots (CDs) carried with different functional groups (–NH 2 , –OH, and –COOH) and pepsin was analyzed through an in vitro digestion model. The results showed that CDs significantly reduced pepsin activity. Among them, CDs–NH 2 had the greatest effect, following by CDs–OH, and CDs–COOH. Besides, molecular docking demonstrated the specific binding site of CDs to pepsin, while the most stable binding energy (–8.10 kcal/mol) was formed between CDs–NH 2 and pepsin. Further, CDs formed a nanomaterial–protein crown structure with pepsin. The present study enriches the functional group properties of CDs in the digestion and provides new ideas for the potential human health of NMs.
研究领域:
生物化学
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食品科学
·
纳米生物学
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DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2026
·Vol. 14
·期 6
·125327
·
IF 7.5
Wencong Fan,Xianhao Jiang,Jing Zhang,Zejia Song,Yawei Shi,Ya Sun,Guanghui Ding
Pepsin promotes the DBP release from PVC-MPs. • Smaller PVC-MPs with higher DBP contents exhibit higher release amounts. • Competitive adsorption of pepsin weakens the DBP binding with PVC-MPs. • Electrostatic, vdW interactions and hydrogen bonds with pepsin drive the DBP release. Ubiquitous microplastics (MPs) can be inadvertently ingested by organisms, and plasticizers released from them may pose potential exposure risks to wildlife and humans. However, the release behavior of dibutyl phthalate (DBP) from polyvinyl chloride (PVC) MPs in digestive tract environments remains poorly understood. In this study, the release behavior of DBP from PVC-MPs under simulated gastric fluid (SGF) conditions was investigated, with particular emphasis on the effects of microplastic characteristics and pepsin. It was found that smaller particle size and higher DBP content resulted in greater DBP release from PVC-MPs. In addition, the presence of pepsin facilitated DBP release. The maximum release amount of DBP was measured to be 1.536 mg/g in pepsin-containing SGF, which was 1.62 times that observed in pepsin-free SGF. Meanwhile, the release rate constant of DBP in pepsin-containing SGF was up to 1.79 times that in pepsin-free SGF. Molecular dynamics simulations suggested that pepsin could bind to the PVC-MP surface, potentially alter the interfacial interactions between PVC-MPs and DBP, and contribute to DBP dissociation from PVC-MPs. Density functional theory calculations further indicated that the stronger interaction between pepsin and DBP may contribute to enhanced DBP release, with electrostatic interactions, van der Waals interactions, and hydrogen bonding potentially involved. These findings could improve our understanding of the release behavior of plasticizers from MPs under SGF conditions. Download: Download high-res image (220KB) Download: Download full-size image
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DOI
高影响因子
危险品化学品经营许可证（带存储）