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Biochimica Et Biophysica Acta May 2005We have reported that ovalbumin accumulates without digestion in various tissues during embryonic development of the chicken. There are different types of ovalbumin with...
We have reported that ovalbumin accumulates without digestion in various tissues during embryonic development of the chicken. There are different types of ovalbumin with respect to thermal stability and one of them, which was named "HS-ovalbumin" in the present study, was found to have a T(m) value of 83 degrees C and to be present dominantly in albumen, egg yolk, amniotic fluid, and serum of fertilized eggs. HS-ovalbumin, arising physiologically from its native form (N-ovalbumin), is reminiscent of the previously described intermediate form appearing during the production processes of the so-called S-ovalbumin, which disappeared shortly in fertilized eggs. We showed that HS-ovalbumin is distinguishable from S-ovalbumin by a monoclonal antibody and also from N-ovalbumin by the stability to heating. At the late stages of development, ovalbumin of amniotic fluid seems to be swallowed through pharynx, carried in the intestine through stomach, and absorbed in the blood. Analyses by monoclonal antibody and heat treatment indicated that the HS-form occupies the largest fraction of ovalbumin that accumulates in the embryonic tissues. The current findings suggest that HS-ovalbumin is crucial for embryogenesis.
Topics: Animals; Antibody Specificity; Calorimetry, Differential Scanning; Chick Embryo; Hot Temperature; Immunohistochemistry; Mice; Mice, Inbred BALB C; Ovalbumin
PubMed: 15866518
DOI: 10.1016/j.bbagen.2005.02.016 -
Bioscience, Biotechnology, and... May 2005Ovalbumin, a member of the serpin superfamily, is transformed into a thermostabilized form, S-ovalbumin, during storage of shell eggs or by an alkaline treatment of the...
Ovalbumin, a member of the serpin superfamily, is transformed into a thermostabilized form, S-ovalbumin, during storage of shell eggs or by an alkaline treatment of the isolated protein (DeltaT(m)=8 degrees C). As structural characteristics of S-ovalbumin, three serine residues (Ser164, Ser236 and Ser320) take the D-amino acid residue configuration, while the conformational change from non-thermostabilized native ovalbumin is very small. To assess the role of the structural characteristics on protein thermostabilization, ovalbumin and S-ovalbumin were denatured to eliminate the conformational modulation effects and then refolded. The denatured ovalbumin and S-ovalbumin were correctly refolded into the original non-denatured forms with the corresponding differential thermostability. There was essentially no difference in the disulfide structures of the native and refolded forms of ovalbumin and S-ovalbumin. These data are consistent with the view that the configuration inversion, which is the only chemical modification directly detected in S-ovalbumin so far, plays a central role in ovalbumin thermostabilization. The rate of refolding of S-ovalbumin was greater than that of ovalbumin, indicating the participation, at least in part, of an increased folding rate for thermodynamic stabilization.
Topics: Hot Temperature; Kinetics; Ovalbumin; Protein Denaturation; Protein Folding; Protein Renaturation; Time Factors
PubMed: 15914911
DOI: 10.1271/bbb.69.922 -
FEBS Letters Jan 1993A protein family, the 'Ov-serpins' has been identified by comparing amino acid sequence, protein characteristics and gene organization. The Ov-serpins would not be... (Comparative Study)
Comparative Study
A protein family, the 'Ov-serpins' has been identified by comparing amino acid sequence, protein characteristics and gene organization. The Ov-serpins would not be recognized as a family based on sequence identity alone. This example suggests that combinations of characteristics may need to be examined to identify family groupings within the serpin superfamily.
Topics: Animals; Chickens; Genes; Humans; Molecular Sequence Data; Multigene Family; Ovalbumin; Protein Sorting Signals; Sequence Alignment; Sequence Homology, Amino Acid; Serpins
PubMed: 8417965
DOI: 10.1016/0014-5793(93)81143-n -
Journal of Agricultural and Food... Jul 2023Egg is one of the eight major food allergens, and ovalbumin (OVA) is the most abundant allergenic protein in eggs. In this study, the effects of pulsed electric field...
Egg is one of the eight major food allergens, and ovalbumin (OVA) is the most abundant allergenic protein in eggs. In this study, the effects of pulsed electric field (PEF)-assisted Alcalase hydrolysis on the spatial conformation and potential allergenicity of OVA were studied, and the mechanism of its inhibiting allergic reactions effect was revealed. PEF-assisted Alcalase hydrolysis increased the degree of hydrolysis, surface hydrophobicity, and free sulfhydryl group content. Moreover, the reduction in the α-helix content, fluorescence intensity, and disulfide bond content suggested that PEF promoted the OVA hydrolysis by Alcalase. Additionally, enzyme-linked immunosorbent assay data indicated that PEF-assisted Alcalase hydrolysis hindered OVA binding to immunoglobulins E and G1. Finally, based on bioinformatics combined with mass spectrometry, PEF-assisted Alcalase reduced OVA-induced allergic reactions by destroying epitopes in OVA. Overall, PEF technology further destroyed the epitopes of allergens by targeting the binding sites of substrates and enzymes to improve the affinity of enzymes and substrates, reducing allergic reactions.
Topics: Humans; Ovalbumin; Epitopes; Subtilisins; Food Hypersensitivity; Allergens
PubMed: 37389912
DOI: 10.1021/acs.jafc.3c02675 -
Food Chemistry Nov 2023This study aimed to form a novel emulsion gel (EG) through structured oil phase of natural component beeswax (BW), together with ovalbumin (OVA), and to investigate the...
This study aimed to form a novel emulsion gel (EG) through structured oil phase of natural component beeswax (BW), together with ovalbumin (OVA), and to investigate the mechanism of its formation and stabilization in terms of microstructure and processing properties. Confocal laser scanning microscopy (CLSM) demonstrated that the EG formed a continuous double network structure since the superior crystallinity of the oil phase was given by BW. Fourier transform infrared spectroscopy (FT-IR) illustrated that the acylation of the phenolic hydroxyl group in BW with an amide bond in OVA, increased the hydrogen bonding of EG. Furthermore, the immobilization of the oil phase results in better thermal and freeze-thaw stability of EG. Finally, EG was used as a curcumin delivery system, and the presence of BW significantly improved its adaptability to multiple environmental factors. In summary, our study would provide valuable ideas for developing the design of finely structured functional food.
Topics: Emulsions; Ovalbumin; Spectroscopy, Fourier Transform Infrared; Waxes
PubMed: 37321120
DOI: 10.1016/j.foodchem.2023.136575 -
Biomacromolecules Mar 2023Ovalbumin (OVA)/sodium carboxymethylcellulose (CMC) colloidal particles were prepared with different compactness and morphologies by regulating the interaction between...
Ovalbumin (OVA)/sodium carboxymethylcellulose (CMC) colloidal particles were prepared with different compactness and morphologies by regulating the interaction between proteins and polysaccharides during heating. Electrostatic interactions between the amine groups of OVA (-NH) and carboxyl groups of CMC (-COO) enhanced complex formation. The protein conformation change benefited the hydrophobic interaction between the particles. Proteins in colloidal particles were unfolded/folded under thermal induction to form aggregates having more β-sheet structures. When the OVA/CMC ratio was 1:2, the initially loosely connected OVA/CMC aggregation changed into a uniform sphere between 25 and 90 °C. The mass ratio of OVA to CMC within the final colloidal particle (90 °C) was about 1:1.4. The OVA/CMC particle stability was maintained with hydrogen bonding, hydrophobicity, and disulfide bond. When OVA levels were predominant, OVA and CMC developed an approximately hollow sphere. Moreover, the final colloidal particle composition showed the OVA-to-CMC ratio as 3:1 (w/w). OVA bound into colloidal particle pores to increase compactness. Moreover, OVA and CMC bound to the colloidal particle while the particle shrank, thereby increasing the compactness of colloidal particles. There was a significant decrease in ABTS scavenging activity of curcumin compared with that of the particles with a ratio of 1:2. Thus, the rational adjustment of the structure of colloidal particles could effectively enhance their functional characteristics, providing a new way for the controlled release of the active ingredients.
Topics: Ovalbumin; Carboxymethylcellulose Sodium
PubMed: 36908256
DOI: 10.1021/acs.biomac.3c00063 -
Proceedings of the National Academy of... Dec 1978By recombinant DNA methods, the chicken ovalbumin structural gene has been fused to Escherichia coli lac transcriptional and translational control regions. When a...
By recombinant DNA methods, the chicken ovalbumin structural gene has been fused to Escherichia coli lac transcriptional and translational control regions. When a plasmid containing the hybrid gene was introduced into E. coli, a protein identified as ovalbumin by immunoreactivity and sodium dodecyl sulfate/polyacrylamide gel electrophoresis was synthesized. The chicken ovalbumin made in bacteria was full length (43,000 daltons) and constituted 1.5% of the cellular protein. In addition, the microbially synthesized ovalbumin was secreted through the cell membrane into the periplasmic space of E. coli. The ability of the E. coli secretory apparatus to recognize chicken ovalbumin, which is normally synthesized and secreted in hen oviducts, suggests that common features exist in the secretion-recognition mechanisms found in these two organisms. The bacterial synthesis of significant amounts of chicken ovalbumin demonstrates that the E. coli cellular machinery may be utilized to synthesize a higher eukaryotic protein which is relatively stable in the bacterial intracellular environment.
Topics: Alkaline Phosphatase; Amino Acid Sequence; DNA, Recombinant; Escherichia coli; Lac Operon; Ovalbumin; Plasmids; beta-Galactosidase
PubMed: 104296
DOI: 10.1073/pnas.75.12.5936 -
Journal of Biochemistry May 1976Hen's oviduct polysomes are present in the precipitates prepared from the oviduct homogenates by low-speed centrifugation, in constrast other eukaryotic polysomes. The...
Hen's oviduct polysomes are present in the precipitates prepared from the oviduct homogenates by low-speed centrifugation, in constrast other eukaryotic polysomes. The polysomes possessed synthesizing activity for ovalbumin. The amount of the released form of ovalbumin (soluble ovalbumin) synthesized in cell-free system A or B, consisting of the cell sap and the total ribosomal fraction or the polysomes, respectively, was about a half of that bound to the polysomes (nascent ovalbumin). The amount of soluble ovalbumin synthesized in cell-free system C, consisting of the pH 5 fraction and the polysomes, was only about 5% of that of nascnet ovalbumin. These results indicate that factors required to release nascent ovalbumin from polysomes are present in the pH 5 supernatant fraction. The soluble and nascent ovalbumins, which were purified by chromatography on a CM-cellulose column and by the use of antiovalbumin antiserum, respectively, seemed to be elongation products the initiations of which were supposed to occur in the oviducts before preparation of the cell-free system. The initiated chains in vitro were found to exist as nascent peptides bound to polysomes. Thus, the cell-free systems prepared in the present study lacked the ability to complete initiated peptide chains. The soluble ovalbumin synthesized in the cell-free systems was indentical with ovalbumin A1 containing two residues of phosphates, which was crystallized from hen's egg-white and was different soluble ovalbumin devoid of the prosthetic group (ovalbumin A3) prepared in the oviduct minces. This result suggests that an enzyme necessary for incorporation of the phosphate is present in the cell sap.
Topics: Adenosine Triphosphate; Animals; Cell-Free System; Chickens; Chromatography, Affinity; Dithiothreitol; Female; Kinetics; Leucine; Ovalbumin; Oviducts; Polyribosomes; Proline; Protein Biosynthesis
PubMed: 956139
DOI: 10.1093/oxfordjournals.jbchem.a131154 -
Food Chemistry Aug 2021The mechanism by which sodium tripolyphosphate affected the aggregation behavior of ovalbumin-lysozyme complexes was investigated in this work. The highest stability...
The mechanism by which sodium tripolyphosphate affected the aggregation behavior of ovalbumin-lysozyme complexes was investigated in this work. The highest stability coefficients were detected for natural ovalbumin and lysozyme at pH 9.0 and pH 5.0, with values of 0.981 and 0.931, respectively. The turbidity of the phosphorylated ovalbumin-lysozyme complexes was 1.71-fold to the natural complexes at pH 7.0. This result was related to the fact that the phosphorylated sample had a lower isoelectric point. Besides, both intermolecular forces and SDS-PAGE analysis indicated that the disulfide bond was the most important interaction in the complex. Circular dichroism analysis showed that phosphorylation weakened the unfolding and stretching of the structure caused by heat treatment. Moreover, transmission electron microscopy pictures confirmed that the network structure of phosphorylated ovalbumin-lysozyme complex was broader than natural protein. This study provides information for further understanding the effect of phosphorylation on protein aggregation behavior.
Topics: Hydrogen-Ion Concentration; Muramidase; Ovalbumin; Phosphorylation; Polyphosphates; Protein Aggregates; Protein Binding
PubMed: 33706135
DOI: 10.1016/j.foodchem.2021.129457 -
Poultry Science Mar 2019In addition to small amounts of minerals and carbohydrates, most of the dry matter of chicken egg white is protein, making egg white an ideal resource for obtaining food...
In addition to small amounts of minerals and carbohydrates, most of the dry matter of chicken egg white is protein, making egg white an ideal resource for obtaining food proteins. Ovalbumin (OVA), which accounts for more than 50% of the total egg white protein, is one of the most widely studied food proteins due to its multiple functional properties, and it has also been used as a model protein molecule in many research fields. The objective of this study was to develop a simple and rapid method for the purification of OVA from egg whites on large scale. First, OVA was separated from ovomucin, ovotransferrin, and ovomucoid by polyethylene glycol (PEG) concentration, using the following optimal parameters: the PEG concentration was 15%, the pH was 6.5, the salt concentration was 100 mmol/L, and the operating temperature was 10°C. The OVA-rich supernatant obtained from PEG precipitation was further purified by isoelectric precipitation at a pI of 4.5 and a temperature of 4°C, and the purified OVA was obtained with at a purity of 95.1% by HPLC, with a yield of 46.4%. After the extraction of OVA, the PEG solution was vacuum dried and then utilized cyclically in the PEG precipitation steps. The whole purification process could be finished within 2 to 3 h at a scale of several kilograms of egg white. This method has the advantages of rapidity, simplicity, low cost, and ease of scalability.
Topics: Animals; Chemical Precipitation; Chickens; Egg White; Ovalbumin; Polyethylene Glycols
PubMed: 30184130
DOI: 10.3382/ps/pey402