Title
Deglycosylation of ovalbumin prohibits formation of a heat-stable conformer
Author
de Groot, J.
Kosters, H.A.
de Jongh, H.H.J.
TNO Kwaliteit van Leven
Publication year
2007
Abstract
To study the influence of the carbohydrate-moiety of ovalbumin on the formation of the heat-stable conformer S-ovalbumin, ovalbumin is deglycosylated with PNGase-F under native conditions. Although the enzymatic deglycosylation procedure resulted in a complete loss of the ability to bind to Concavalin A column-material, only in about 50% the proteins lost their complete carbohydrate moiety, as demonstrated by mass spectrometry and size exclusion chromatography. Thermal stability and conformational changes were determined using circular dichroism and differential scanning calorimetry and demonstrated at ambient temperature no conformational changes due to the deglycosylation. Also the denaturation temperature of the processed proteins remained the same (77.4 ± 0.4°C). After heat treatment of the processed protein at 55°C and pH 9.9 for 72 h, the condition that converts native ovalbumin into the heat-stable conformer (S-ovalbumin), only the material with the intact carbohydrate moiety forms this heat-stable conformer. The material that effectively lost its carbohydrate moiety appeared fully denatured and aggregated due to these processing conditions. These results indicate that the PNGase-F treatment of ovalbumin prohibits the formation and stabilization of the heat-stable conformer S-ovalbumin. Since S-ovalbumin in egg protein samples is known to affect functional properties, this work illustrates a potential route to control the quality of egg protein ingredients. © 2006 Wiley Periodicals, Inc.
Subject
Nutrition
Food technology
Circular dichroism
Deglycosylation
Ovalbumin
PNGase-F
S-ovalbumin
Size exclusion chromatography
Thermostability
Carbohydrate moiety
Deglycosylation
Ovalbumin
Thermostability
Carbohydrates
Differential scanning calorimetry
Heat treatment
pH effects
Reaction kinetics
Size exclusion chromatography
Thermodynamic stability
Proteins
glycopeptidase
ovalbumin
s ovalbumin
unclassified drug
article
circular dichroism
deglycosylation
differential scanning calorimetry
enzyme binding
gel permeation chromatography
mass spectrometry
protein conformation
protein denaturation
thermostability
Animals
Chickens
Chromatography, Gel
Circular Dichroism
Enzyme Stability
Glycosylation
Heat
Isoelectric Focusing
Mass Spectrometry
Molecular Weight
Ovalbumin
Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase
Protein Conformation
Spectrometry, Fluorescence
To reference this document use:
http://resolver.tudelft.nl/uuid:6d91fe05-1ade-4034-ac75-4759b5fac864
DOI
https://doi.org/10.1002/bit.21264
TNO identifier
240053
ISSN
0006-3592
Source
Biotechnology and Bioengineering, 97 (4), 735-741
Document type
article