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Food Chemistry May 2024When subjected to dry-heating, egg white ovalbumin, a phosphoglycoprotein, undergoes fragmentation and forms soluble aggregates. We investigated the mechanisms of...
When subjected to dry-heating, egg white ovalbumin, a phosphoglycoprotein, undergoes fragmentation and forms soluble aggregates. We investigated the mechanisms of dry-heat-induced fragmentation of ovalbumin. SDS-PAGE analysis showed that ovalbumin fragmented into five polypeptides, and their amount increased over 6 h of dry-heat treatment at 120 °C. The fragments contained fewer or no phosphoserine, compared with that in crude ovalbumin. Liquid chromatography-tandem mass spectrometry analysis of tryptic digests revealed that the fragmentation sites were located on phosphoserine residues, S and S. During fragmentation, the phosphoserine residues underwent conversion into dehydroalanine residues, which were subsequently hydrolyzed. The nitrogen from the dehydroalanine became a newly formed terminal amide group on the N-terminal fragment, while the remaining molecule predominantly formed a new terminal pyruvoyl group. Furthermore, the fragments were incorporated into monomers or soluble aggregates of ovalbumin via covalent and non-covalent bonds. This study demonstrated a novel mechanism for dry-heat-induced fragmentation of phosphoproteins.
Topics: Ovalbumin; Phosphoserine; Hot Temperature; Peptides; Egg White
PubMed: 38159316
DOI: 10.1016/j.foodchem.2023.138263 -
Analytical Biochemistry Jan 2022Ovalbumin particles are reduced to nano size using heat treatment techniques. Their structural patterns in their native state and in their pH denatured state were...
Ovalbumin particles are reduced to nano size using heat treatment techniques. Their structural patterns in their native state and in their pH denatured state were attempted. Denaturation is also a part of conformation and hence conformations due to pH and glucose were analyzed using FTIR spectroscopy. The interactions behind these conformations are unraveled and the role of glucose as cosolvent in restricting the denaturation is also revealed from the observed secondary structures of ovalbumin. Further, the characterization of these synthesized nano particles reveals the extent of their applications. The obtained results indicate that consideration of ovalbumin nanoparticles seems to favor a very clear trend of protein denaturation and the observed structural modifications are the result of development of non-covalent interactions by the cosolvent molecules.
Topics: Nanoparticles; Ovalbumin; Protein Structure, Secondary; Spectroscopy, Fourier Transform Infrared
PubMed: 34774535
DOI: 10.1016/j.ab.2021.114456 -
The Journal of Allergy and Clinical... Apr 2023Elongation of very-long-chain fatty acids protein 6 (ELOVL6), an enzyme regulating elongation of saturated and monounsaturated fatty acids with C12 to C16 to those with...
BACKGROUND
Elongation of very-long-chain fatty acids protein 6 (ELOVL6), an enzyme regulating elongation of saturated and monounsaturated fatty acids with C12 to C16 to those with C18, has been recently indicated to affect various immune and inflammatory responses; however, the precise process by which ELOVL6-related lipid dysregulation affects allergic airway inflammation is unclear.
OBJECTIVES
This study sought to evaluate the biological roles of ELOVL6 in allergic airway responses and investigate whether regulating lipid composition in the airways could be an alternative treatment for asthma.
METHODS
Expressions of ELOVL6 and other isoforms were examined in the airways of patients who are severely asthmatic and in mouse models of asthma. Wild-type and ELOVL6-deficient (Elovl6) mice were analyzed for ovalbumin-induced, and also for house dust mite-induced, allergic airway inflammation by cell biological and biochemical approaches.
RESULTS
ELOVL6 expression was downregulated in the bronchial epithelium of patients who are severely asthmatic compared with controls. In asthmatic mice, ELOVL6 deficiency led to enhanced airway inflammation in which lymphocyte egress from lymph nodes was increased, and both type 2 and non-type 2 immune responses were upregulated. Lipidomic profiling revealed that the levels of palmitic acid, ceramides, and sphingosine-1-phosphate were higher in the lungs of ovalbumin-immunized Elovl6 mice compared with those of wild-type mice, while the aggravated airway inflammation was ameliorated by treatment with fumonisin B1 or DL-threo-dihydrosphingosine, inhibitors of ceramide synthase and sphingosine kinase, respectively.
CONCLUSIONS
This study illustrates a crucial role for ELOVL6 in controlling allergic airway inflammation via regulation of fatty acid composition and ceramide-sphingosine-1-phosphate biosynthesis and indicates that ELOVL6 may be a novel therapeutic target for asthma.
Topics: Animals; Mice; Asthma; Ceramides; Disease Models, Animal; Inflammation; Ovalbumin
PubMed: 36592705
DOI: 10.1016/j.jaci.2022.12.808 -
Talanta Apr 2021SARS-COV-2 is a novel coronavirus discovered in Wuhan in December 30, 2019, and is a family of SARS-COV (severe acute respiratory syndrome coronavirus), that is,... (Review)
Review
SARS-COV-2 is a novel coronavirus discovered in Wuhan in December 30, 2019, and is a family of SARS-COV (severe acute respiratory syndrome coronavirus), that is, coronavirus family. After infection with SARS-COV-2, patients often experience fever, cough, gas prostration, dyspnea and other symptoms, which can lead to severe acute respiratory syndrome (SARS), kidney failure and even death. The SARS-COV-2 virus is particularly infectious and has led to a global infection crisis, with an explosion in the number of infections. Therefore, rapid and accurate detection of the virus plays a vital role. At present, many detection methods are limited in their wide application due to their defects such as high preparation cost, poor stability and complex operation process. Moreover, some methods need to be operated by professional medical staff, which can easily lead to infection. In order to overcome these problems, a Surface molecular imprinting technology (SM-MIT) is proposed for the first time to detect SARS-COV-2 virus. For this SM-MIT method, this review provides detailed detection principles and steps. In addition, this method not only has the advantages of low cost, high stability and good specificity, but also can detect whether it is infected at designated points. Therefore, we think SM-MIT may have great potential in the detection of SARS-COV-2 virus.
Topics: COVID-19; Humans; Magnetite Nanoparticles; Microspheres; Molecular Imprinting; Ovalbumin; Polymers; SARS-CoV-2; Sensitivity and Specificity; Viral Proteins
PubMed: 33592725
DOI: 10.1016/j.talanta.2020.121977 -
Food Chemistry Sep 2022The effect of ovalbumin-flavonoids (naringenin, genistein, naringin, puerarin, and daidzein) interactions on the formation and properties of ovalbumin hydrogels was...
The effect of ovalbumin-flavonoids (naringenin, genistein, naringin, puerarin, and daidzein) interactions on the formation and properties of ovalbumin hydrogels was investigated. The results suggested that flavonoids were able to promote the gelation of low concentration ovalbumin solution, which was not able to form hydrogel upon heating. All hydrogels formed by flavonoids and ovalbumin were more elastic than viscous. The hydrogels formed by naringenin and ovalbumin showed the strongest gel hardness, springiness, and water holding capacity. Fluorescence spectroscopy and molecular docking analysis revealed that the main interactions between ovalbumin and naringenin, genistein, puerarin, naringin were hydrogen bond, while the main interaction between ovalbumin and daidzein was hydrophobic force. Flavonoids, which have a structure with more phenolic hydroxyl groups, a C2 = C3 double bond and dehydrogenated glycosides, possessed higher affinity to ovalbumin. This research provides new insights into mechanism of ovalbumin-flavonoids interactions and its influence on the formation and property of hydrogel.
Topics: Flavonoids; Genistein; Hydrogels; Molecular Docking Simulation; Ovalbumin
PubMed: 35405558
DOI: 10.1016/j.foodchem.2022.132892 -
International Journal of Biological... Jun 2023The polymeric materials formed by proteins and polysaccharides through molecular interactions have attracted public attention. In this study, a novel binary complex...
The polymeric materials formed by proteins and polysaccharides through molecular interactions have attracted public attention. In this study, a novel binary complex consisting of ovalbumin (OVA) and fucoidan (FUC) was obtained by electrostatic self-assembly. The self-assembly properties and the formation mechanism of the OVA-FUC binary complex were investigated by changing the charging degree and density of complex through altering pH value and polysaccharides proportion. Structural changes during the OVA-FUC electrostatic self-assembly process were investigated by a phase diagram, ζ-potential, and particle size. The optimal conditions for preparing soluble OVA-FUC binary complex were determined by the protein retention rate and insoluble solids content. Results showed that the soluble OVA-FUC binary complex could be obtained at the pH of 3.5 to 5, and the insoluble OVA-FUC binary complex was generated at the pH of 2.5 to 3.5. The OVA-FUC binary complex (19 ± 0.29 mN/m) possessed a medium ability to reduce interfacial tension of the water-oil interface compared with OVA (15 ± 1.13 mN/m) and FUC (24 ± 0.3 mN/m), indicating that OVA-FUC binary complex has good amphiphilicity and can be applied as a potential pH-controlled emulsifier in function food systems for delivering bioactive substances.
Topics: Ovalbumin; Polysaccharides; Emulsifying Agents
PubMed: 37121411
DOI: 10.1016/j.ijbiomac.2023.124644 -
Investigative Ophthalmology & Visual... Apr 2023Allergic conjunctivitis (AC) is a common allergic condition worldwide that requires accurate screening and early diagnosis. We found that gp130 is essential for AC, as...
PURPOSE
Allergic conjunctivitis (AC) is a common allergic condition worldwide that requires accurate screening and early diagnosis. We found that gp130 is essential for AC, as gp130 levels are elevated in AC. Therefore, this study aimed to elucidate the functions and the possible underlying mechanisms of gp130 in AC.
METHODS
To compare mRNA expression profiles, the conjunctival tissues of BALB/c mice with ovalbumin (OVA)-induced AC were subjected to RNA-sequencing (RNA-seq) analysis followed by bioinformatic analysis. A nonrandomized study involving 57 patients with AC and 24 sex- and age-matched healthy individuals was conducted. A protein chip was used to detect cytokine levels in patient tears. Differentially expressed proteins in patient serum were detected using label-free quantitative mass spectrometry. Histamine-stimulated conjunctival epithelial cells (HConEpiCs) were used to construct a cell model. LMT-28 which can inhibit gp130 phosphorylation was dropped onto the murine ocular surface, and the resulting symptoms were observed.
RESULTS
Gp130 is upregulated in the conjunctival tissues of OVA-induced mice, the serum and tears of patients, and the histamine-stimulated HConEpiCs. Signal transducer and activator of transcription 3 (STAT3) and Janus kinase 2 (JAK2) were upregulated in the conjunctival tissues of mice with OVA-induced AC and in HConEpiCs. Ocular surface inflammation was significantly relieved in LMT-28-treated mice. The expression of IgE, IL-4, IL-5, and IL-13 in serum of LMT-28-treated mice decreased. The number of mast cells in conjunctival tissue was decreased compared with OVA-induced mice.
CONCLUSIONS
Gp130 may play an important role in AC via the gp130/JAK2/STAT3 pathway. Inhibiting gp130 phosphorylation alleviates ocular surface inflammation in mice, presenting a potential treatment approach for AC.
Topics: Animals; Mice; Conjunctivitis, Allergic; Janus Kinase 2; Cytokine Receptor gp130; Ovalbumin; Histamine; STAT3 Transcription Factor; Inflammation
PubMed: 37022703
DOI: 10.1167/iovs.64.4.5 -
Food Chemistry Oct 2022In this study, ovalbumin (OVA) formed a complex with neohesperidin (NH) via a pH-shifting method. The NH-OVA complex self-assembled into NH-OVA nano-particles, which...
In this study, ovalbumin (OVA) formed a complex with neohesperidin (NH) via a pH-shifting method. The NH-OVA complex self-assembled into NH-OVA nano-particles, which were then characterized and whose binding mechanism was evaluated by using multi-spectroscopic, thermodynamics, and molecular docking simulation methods. Fluorescence intensity decreased after OVA was complexed with NH. The binding constant of the OVA-NH complex was in the order of 6.32 × 10 M suggesting that the complex is stable. Circular dichroism (CD) analysis showed that α -helix content increased, β-folding, β -turning, and irregular crimp content decreased after OVA and NH binding. Isothermal titration calorimetry results showed that hydrophobic interactions and hydrogen bonds made an important impact in the complex formation. The molecular docking results revealed that Van der Waals forces and hydrogen bonds contributed to the free binding energy of the complex. There were multiple possible surface binding sites between OVA with NH. The obtained results provide new insights into the interaction mechanism of OVA and NH, and as a vehicle for NH, the OVA has shown promising applications in functional foods.
Topics: Binding Sites; Circular Dichroism; Hesperidin; Hydrogen-Ion Concentration; Molecular Docking Simulation; Ovalbumin; Protein Binding; Spectrometry, Fluorescence; Thermodynamics
PubMed: 35561507
DOI: 10.1016/j.foodchem.2022.133104 -
Analytical and Bioanalytical Chemistry Jul 2022A strategy to design imprinted proteins (IPs) able to detect a glycoprotein (ovalbumin, OVA) was proposed. Glucose oxidase (GOx) was used as a matrix for obtaining the...
A strategy to design imprinted proteins (IPs) able to detect a glycoprotein (ovalbumin, OVA) was proposed. Glucose oxidase (GOx) was used as a matrix for obtaining the binding cavities with high specificity towards the template protein. The effective method to purify the obtained IPs from the template molecules was developed based on a combination of dialysis and gel filtration. HRP was chosen as a model template to discover the optimal production conditions, and the optimal template concentration (100 µg⋅L) was chosen. The obtained imprinted proteins were characterized by the high adsorption selectivity towards the target protein (the imprinting factor towards OVA and HRP is 4.7). The developed method was transferred to the synthesis of the anti-OVA IPs. The binding properties of these IPs were estimated using the OVA conjugates with low- (FITC) and high- (HRP) molecular weight label molecules. The ability of the synthesized anti-OVA IPs as recognition elements in immunoassay was studied. Under the optimized experimental conditions, the proposed imprinted proteins exhibited a good linear response to OVA in the concentration range of 10-2000 ng⋅mL with a detection limit of 6 ng⋅mL. The obtained recognition elements were tested for OVA determination in real samples of chicken egg white, and a sample of OVA-free cake spiked by OVA.
Topics: Glucose Oxidase; Glycoproteins; Immunoassay; Molecular Imprinting; Ovalbumin
PubMed: 35303137
DOI: 10.1007/s00216-022-04009-3 -
Nanomedicine : Nanotechnology, Biology,... Jun 2022Nanoparticles hold great potential as vaccine carriers due to their highly versatile structure and the possibility to influence intracellular trafficking and antigen...
Nanoparticles hold great potential as vaccine carriers due to their highly versatile structure and the possibility to influence intracellular trafficking and antigen presentation by their design. In this study, we developed a nanoparticulate system with a new enzyme-triggered antigen release mechanism. For this novel approach, nanoparticle and model antigen ovalbumin were linked with a substrate of the early endosomal protease cathepsin S. This construct enabled the transfer of antigens delivered to bone marrow-derived dendritic cells from the endo-lysosomal compartments in the cytosol. Consecutively, our particles enhanced cross-presentation on dendritic cells and subsequently promoted a stronger activation of CD8 T cells. Our findings suggest that enzyme-triggered antigen release allows the endosomal escape of the antigen, leading to increased MHC-I presentation. Since T cell immunity is central for the control of viral infections and cancer, this release mechanism offers a promising approach for the development of both prophylactic and therapeutic vaccines.
Topics: Animals; Antigen Presentation; Antigens; CD8-Positive T-Lymphocytes; Cross-Priming; Dendritic Cells; Mice; Mice, Inbred C57BL; Ovalbumin; Vaccines
PubMed: 35283290
DOI: 10.1016/j.nano.2022.102545