During incubation of gamma-globulin preparations under conditions similar to physiological ones within 28 days (0.9% NaCl, pH 7.0, 37 degrees) as well as during storage at 3-10 degrees within 36 months gradual nonenzymatic deamidation of the protein occurred mainly due to hydrolysis of readily accessible amide groups (asparagine). Fluorescence of the preparations decreased gradually in the course of deamidation; it constituted for 82% of the initial value after incubation during 28 days. Immunological activity of the gamma-globulin, which lost 19.6% of amide groups, was decreased by 34%; alteration in the amidation by 45.1% was accompanied by a decrease in active antibodies concentration by 92.3%. Nonenzymatic deamidation may be responsible for conformational alterations and inactivation of gamma-globulin.
Download full-text PDF |
Source |
---|
Anal Methods
December 2024
School of Chemistry and Molecular Engineering and Research Centre of Analysis and Test, East China University of Science and Technology, Shanghai, 200237, P. R. China.
A robust deamidation quantification method, called QuanDA, was developed to quantify the spontaneous nonenzymatic deamidation of peptides based on the isotopic distribution change of peptides in matrix-assisted laser desorption ionization (MALDI) mass spectra and non-negative least squares calculation. The predictive model of QuanDA using theoretical spectra of pure un-deamidated and deamidated peptides for a series of simulated partial deamidated peptides is satisfying, with a coefficient of determination () and root mean squared error (RMSE) of 0.9914 and 0.
View Article and Find Full Text PDFAppl Spectrosc
February 2024
Infectious Disease Research, Department of Materials Sciences and Engineering, University of Delaware, Newark, Delaware, USA.
Clinical antibodies are an important class of drugs for the treatment of both chronic and acute diseases. Their manufacturability is subject to evaluation to ensure product quality and efficacy. One critical quality attribute is deamidation, a non-enzymatic process that is observed to occur during thermal stress, at low or high pH, or a combination thereof.
View Article and Find Full Text PDFJ Proteome Res
February 2024
Discovery Proteomics, Amgen Research, South San Francisco, California 94080, United States.
Antibodies (Basel)
October 2023
Department of Process and Analytical Sciences, Biopharmaceutical Development, BioPharmaceuticals R&D, AstraZeneca, One Medimmune Way, Gaithersburg, MD 20878, USA.
Asparagine deamidation is a post-translational modification (PTM) that converts asparagine residues into iso-aspartate and/or aspartate. Non-enzymatic asparagine deamidation is observed frequently during the manufacturing, processing, and/or storage of biotherapeutic proteins. Depending on the site of deamidation, this PTM can significantly impact the therapeutic's potency, stability, and/or immunogenicity.
View Article and Find Full Text PDFTalanta
January 2024
Barnett Institute of Chemical and Biological Analysis, Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, United States. Electronic address:
Charge variant characterization of biologics is critical to ensure that product meets the required quality and regulatory requirements to ensure safety and efficacy of the biotherapeutic. Charge variants arise from post-translation modifications (PTMs) during upstream processing and due to enzymatic and non-enzymatic chemical reactions that occur during downstream processing and storage. Some of these modifications may impact therapeutic potency, efficacy, or immunogenicity of a biotherapeutic.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!