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Food Chemistry Mar 2021An important relationship exists between the changes in glycation sites and structure of proteins. A combination of liquid chromatography and tandem mass spectrometry...
An important relationship exists between the changes in glycation sites and structure of proteins. A combination of liquid chromatography and tandem mass spectrometry was used to identify the glycation information from ovalbumin (OVA) after dextran (Dex) conjugation under water heating (WH) or microwave heating (MH) conditions. After Dex conjugation, 12O-linked glycation sites were identified in the OVA-Dex-MH conjugates, whereas 6O-linked, 2N-linked glycation sites were detected in the OVA-Dex-WH conjugates. These findings indicate that the amino acids at different positions in OVA molecular structure have different glycation reactivity under MH or WH induction systems. In addition, β-sheet and β-turn structures showed high glycation reactivity. The increased surface hydrophobicity of OVA-Dex conjugates was possibly attributed to the glycation sites that were mainly found in hydrophilic amino acids. Our study provides useful information for the glycation mechanism research of OVA and Dex.
Topics: Chromatography, Liquid; Dextrans; Glycation End Products, Advanced; Glycosylation; Hydrophobic and Hydrophilic Interactions; Microwaves; Ovalbumin; Serine; Tandem Mass Spectrometry; Threonine
PubMed: 33035859
DOI: 10.1016/j.foodchem.2020.128066 -
Journal of Animal Physiology and Animal... Oct 2016Three trials were performed to evaluate the association of ovalbumin (OVA) abundance in the oviduct magnum with egg production and the underlying regulatory mechanism by... (Randomized Controlled Trial)
Randomized Controlled Trial
Three trials were performed to evaluate the association of ovalbumin (OVA) abundance in the oviduct magnum with egg production and the underlying regulatory mechanism by glucocorticoids. In trial 1, twenty Hy-Line Brown layers (56-60 weeks of age) with different combinations (n = 5/combination) of laying rate (high or low) and egg weight (high or low) were selected from an initial group of 300. An upregulated expression of magnum OVA was observed (p < 0.05) in hens with higher laying rate, regardless of egg weight. In trial 2, eighty Hy-Line Brown layers (80-90 weeks of age) were subjected to the forced moulting (n = 8). The abundance of OVA transcript and protein in the magnum was significantly decreased during moulting (p < 0.01), and the same was true for laying rate (p < 0.01) and serum oestrogen (p < 0.05). In trial 3, forty-five 56-week-old Hy-Line Brown layers were kept individually (n = 15) in the following conditions for 10 days: constant optimal ambient temperature at 23 °C and ad libitum feeding, high ambient temperature at 32 °C for 6 h/day (10:00-16:00) and ad libitum feeding (32AL), and constant optimal ambient temperature at 23 °C and pair-fed to the 32AL hens. In spite of elevated corticosterone in circulation, OVA synthesis, blood oestrogen and laying rate were not affected by heat exposure (p > 0.05). These results allow concluding that OVA expression in the oviduct magnum of hens is related to the rate of egg laying and shows distinct stress-type-specific responses.
Topics: Animals; Chickens; Eggs; Female; Ovalbumin; Oviducts; Oviposition; Stress, Physiological
PubMed: 27271712
DOI: 10.1111/jpn.12475 -
Journal of Agricultural and Food... Mar 2022Melibiose, cellobiose, maltose, lactose, turanose, and isomaltulose were selected to be glycated with OVA. The number of free amino groups of OVA modified with different...
Melibiose, cellobiose, maltose, lactose, turanose, and isomaltulose were selected to be glycated with OVA. The number of free amino groups of OVA modified with different disaccharides decreased, and the secondary and tertiary structures of the modified OVA also changed greatly. Moreover, the glycation sites detected by HPLC-HCD-MS/MS were all on the sensitized epitopes of OVA, which reduced the binding ability of IgG and IgE of glycated OVA. In addition, the glycation sites with the highest DSP in different samples were located in the irregular coil region of OVA. Among the six disaccharides, the glycation reaction between melibiose and OVA was the most obvious. Through the analysis of disaccharide configuration, it was found that the glycation efficiency of the reducing disaccharide linked by a 1 → 6 glycoside bond was higher than that by a 1 → 4 glycoside bond, and reducing sugar with β type was better than that with α type. These findings would provide a theoretical reference for the use of different sugars in food production.
Topics: Chromatography, Liquid; Disaccharides; Glycosylation; Ovalbumin; Tandem Mass Spectrometry
PubMed: 35253441
DOI: 10.1021/acs.jafc.1c03488 -
Ultrasonics Sonochemistry Dec 2023Ovalbumin (OVA), characterized by its high concentration in eggs, possesses remarkable foaming properties. Nevertheless, OVA is highly sensitive to thermal changes and...
Improvement of foaming properties of ovalbumin: Insights into the synergistic effect of preheating and high-intensity ultrasound on physicochemical properties and structure analysis.
Ovalbumin (OVA), characterized by its high concentration in eggs, possesses remarkable foaming properties. Nevertheless, OVA is highly sensitive to thermal changes and acid-base conditions, substantially hampering its application potential for foaming purposes within the food industry. This experiment aimed to examine the effects of preheating and high-intensity ultrasound (HIU) treatment at different powers on OVA foaming properties and explore the underlying mechanisms. The results revealed that OVA exhibited the highest foaming capacity (31.5 %) and foaming stability (96.7 %) under the treatment condition of 200w + 60°C. Additionally, significant improvements were observed in the content of free sulfhydryl groups (37.27 μmg/g), solution viscosity (142.33 mPa·s), and surface hydrophobicity (37.27 μg BPB) under this condition. The absolute value of the zeta potential (-10.28 mV) was significantly increased in the 200w + 60°C treatment group. Moreover, the polymer dispersity index of OVA (0.6045) was significantly reduced, resulting in improved dispersion than the control group. The structural analysis revealed significant changes in the α-helix and β-sheet content of OVA after treatment at 200w + 60 °C. The X-ray diffraction pattern exhibited sharper peaks, indicating a crystal structure, and the fluorescence peak displayed a slight blue shift along with increased hydrophobicity. Moreover, the preheating and HIU treatment induced a continuous uneven and irregular pore structure in OVA, which ultimately enhanced its foaming properties. In conclusion, the preheating and HIU treatment offers a novel approach to enhance the foaming properties of OVA.
Topics: Ovalbumin; Hydrophobic and Hydrophilic Interactions; Viscosity
PubMed: 37925915
DOI: 10.1016/j.ultsonch.2023.106672 -
Biochemistry May 2021Chicken ovalbumin (cOVA) has been studied for decades primarily due to the robust genetic and molecular resources that are available for experimental investigations....
Chicken ovalbumin (cOVA) has been studied for decades primarily due to the robust genetic and molecular resources that are available for experimental investigations. cOVA is a member of the serpin superfamily of proteins that function as protease inhibitors, although cOVA does not exhibit this activity. As a serpin, cOVA possesses a protease-sensitive reactive center loop that lies adjacent to the OVA 323-339 CD4+ T-cell epitope. We took advantage of the previously described single-substitution variant, OVA R339T, which can undergo the dramatic structural transition observed in serpins, to study how changes in loop size and protein stability influence the processing and presentation of the OVA 323-339 epitope. We observed that the OVA R339T loop insertion increases the stability and protease resistance, resulting in the reduced presentation of the OVA 323-339 epitope . These findings have implications for the design of more effective vaccines for the treatment of infectious diseases and cancer as well as the development of more robust CD4+ T-cell epitope prediction tools.
Topics: Animals; Binding Sites; Chickens; Epitopes; Kinetics; Ovalbumin; Peptide Fragments; Serpins; Thermodynamics
PubMed: 33956428
DOI: 10.1021/acs.biochem.1c00095 -
Food Chemistry Mar 2022Glycation can improve the functional properties of protein. However, in vitro and animal studies have shown that glycation induced lysine blockage and impaired protein...
Effect of glycation degree on the structure and digestion properties of ovalbumin: A study of amino acids and peptides release after in vitro gastrointestinal simulated digestion.
Glycation can improve the functional properties of protein. However, in vitro and animal studies have shown that glycation induced lysine blockage and impaired protein digestibility. This study aimed to explore the effects of different glycation degree on the structure and digestive characteristics of ovalbumin. The results showed that glycation decreased the turbidity and hydrophobicity of the protein and changed the protein structure. Moreover, the results of in vitro simulated digestion revealed that glycation reduced the contents of essential amino acids and total amino acids after digestion. Glycation changed the amino acids and peptides release from the protein by resisting the digestion of digestive enzymes, especially trypsin. In conclusion, this work links glycation, protein digestibility, and the release of amino acids and peptides. This emphasizes the importance of the balance between improving properties and ensuring the digestibility of proteins during food processing.
Topics: Amino Acids; Animals; Digestion; Glycosylation; Ovalbumin; Peptides
PubMed: 34731794
DOI: 10.1016/j.foodchem.2021.131331 -
Proceedings of the National Academy of... Jan 1978Ovalbumin mRNA was translated in a reticulocyte lysate. The primary translation product starts with methionine derived from Met-tRNAf. When the nascent polypeptide is...
Ovalbumin mRNA was translated in a reticulocyte lysate. The primary translation product starts with methionine derived from Met-tRNAf. When the nascent polypeptide is about 20 residues long, this methionine is removed. The new NH2-terminal glycine is acetylated from acetyl-CoA when the polypeptide is 44 residues long. The sequence of 35 residues at the NH2 terminus of ovalbumin was determined by automated Edman degradation after a method was devised to prevent acetylation during protein synthesis in the reticulocyte lysate. This sequence is the same as that of secreted ovalbumin and does not resemble the transient "signal peptides" associated with most secretory proteins, including three other egg white proteins synthesized in the same cells as ovalbumin.
Topics: Acetyl Coenzyme A; Acetylation; Amino Acid Sequence; Animals; Cell-Free System; Chickens; Female; Ovalbumin; Oviducts; Protein Biosynthesis; RNA, Messenger
PubMed: 272676
DOI: 10.1073/pnas.75.1.94 -
Materials Science & Engineering. C,... Mar 2015A great number of people suffer from burning injuries all around the world each year. Applying an appropriate wound dressing can promote new tissue formation, prevent...
A great number of people suffer from burning injuries all around the world each year. Applying an appropriate wound dressing can promote new tissue formation, prevent losing water and inhibit invasion of infectious organisms. In this study, egg white with a long standing history, as a homemade remedy, was fabricated as a wound dressing for burn injuries. For this reason, ovalbumin films were cross-linked by 1-ethyl-3-3-dimethyl aminopropyl carbodiimide hydrochloride (EDC) with different concentrations (1, 5 and 10mM) using three concentrations of ethanol. Physical-chemical characterizations including Fourier transform infrared spectroscopy (FTIR), gas transmission rate (GTR), tensile mechanical tests, water uptake and degradation rate were performed on the samples. The sample with 5mM crosslinking agent at 70% ethanol was considered as the optimized one with 417kPa of ultimate tensile strength, 64% elongation at break and 230% water uptake. In addition, biological evaluations conducted by MTT and live/dead assay indicated no sign of cyto-toxicity for all the samples. Moreover, scanning electron microscopy (SEM) showed that the fibroblast cells were well spread on the sample with the formation of filopodia. In conclusion, modified ovalbumin can be applied as the base material for fabrication of wound dressing and skin care products.
Topics: Bandages; Biocompatible Materials; Cell Line; Cross-Linking Reagents; Electrophoresis, Polyacrylamide Gel; Ethyldimethylaminopropyl Carbodiimide; Fibroblasts; Humans; Microscopy, Electron, Scanning; Ovalbumin; Spectroscopy, Fourier Transform Infrared
PubMed: 25579909
DOI: 10.1016/j.msec.2014.11.063 -
International Journal of Biological... Mar 2024The study focused on the regulation of ovalbumin (OVA) allergenicity using pulsed electric field (PEF) technology and examined the structure-activity link. Following PEF...
The study focused on the regulation of ovalbumin (OVA) allergenicity using pulsed electric field (PEF) technology and examined the structure-activity link. Following PEF treatment, the ability of OVA to bind to IgE and IgG1 at 6 kHz was inhibited by 30.41 %. According to the microstructure, PEF caused cracks on the OVA surface. Spectral analysis revealed a blue shift in the amide I band and a decrease in α-helix and β-sheet content indicating that the structure of OVA was unfolded. The disulfide bond conformation was transformed and the structure tended to be disordered. The increased fluorescence intensity indicated that tryptophan and tyrosine were exposed which led an increase in hydrophobicity. In addition, the results of molecular dynamics (MD) simulations confirmed that the stability of OVA was reduced after PEF, which was related to the reduction of hydrogen bonding and the sharp fluctuation of aspartic acid. Therefore, PEF treatment induced the exposure of hydrophobic amino acids and the transformation of disulfide bond configuration which in turn masked or destroyed allergenic epitopes, and ultimately inhibited OVA allergenicity. This study provided insightful information for the production of hypoallergenic eggs and promoted the use of PEF techniques in the food field.
Topics: Ovalbumin; Allergens; Electricity; Eggs; Disulfides
PubMed: 38280703
DOI: 10.1016/j.ijbiomac.2024.129695 -
Food Chemistry Sep 2019To explore the protein surface properties treated by Pulsed Electric Field (PEF) with metal ions, we employed ovalbumin as the object and added three divalent metal ions...
To explore the protein surface properties treated by Pulsed Electric Field (PEF) with metal ions, we employed ovalbumin as the object and added three divalent metal ions (Ca, Cu and Ba), respectively. The changes in surface hydrophobicity and surface tension were evaluated. Raman, FTIR, and fluorescence were used to record their structure variations. The results show that the surface hydrophobicity and surface tension of ovalbumin increased with the adding of metal ions. It was caused by the burial of some hydrophobic residues and variation of hydrophobic interaction between molecules, which was consistent with the results of spectra. With the combination of metal ions and PEF, the surface hydrophobicity and surface tension of ovalbumin showed an enhanced trend at first and then reduced with pulse time. These results demonstrate that metal ions and PEF have crucial influences on surface properties, that might afford a theoretical basis for the production and application of ovalbumin.
Topics: Cations, Divalent; Electricity; Hydrophobic and Hydrophilic Interactions; Metals; Ovalbumin; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Surface Properties
PubMed: 31151634
DOI: 10.1016/j.foodchem.2019.05.016