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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
STUDIES ON THE FORMATION AND IONIZATION OF THE COMPOUNDS OF CASEIN WITH ALKALI : III. THE ELECTROCHEMICAL BEHAVIOR OF
1Department of Biochemistry and Pharmacology of the University of California, Berkeley.
The Journal of General Physiology
|October 30, 2009
Summary
Protein racemization, specifically in casein, was investigated. Experimental data indicate that racemic casein
Area of Science:
- Biochemistry
- Protein Chemistry
- Physical Chemistry
Background:
- Protein racemization is a process where L-amino acids convert to D-amino acids.
- Existing theories, like Dakin's hypothesis and Robertson's theory of protein ionization, attempt to explain this phenomenon.
- Understanding racemization is crucial for protein stability and degradation studies.
Purpose of the Study:
- To investigate protein racemization, focusing on casein.
- To evaluate Robertson's theory of protein ionization in the context of racemic casein.
- To analyze the chemical and electrochemical properties of racemic casein.
Main Methods:
- Electrochemical behavior analysis of racemic casein.
- Nitrogen group analysis of racemic casein and comparison with normal casein.
- Determination of the electrochemical equivalent of racemic casein.
Main Results:
- The electrochemical behavior of racemic casein contradicts deductions from Robertson's theory.
- Analysis of nitrogen groups suggests racemic casein is not a simple degradation product, aside from amide group hydrolysis.
- Evidence indicates that -COHN- groups are not primarily involved in protein reactions with acids and bases.
Conclusions:
- Robertson's theory of protein ionization does not fully explain the behavior of racemic casein.
- Racemic casein, apart from amide hydrolysis, is unlikely a degradation product of native casein.
- The role of -COHN- groups in protein acid-base reactions is limited.
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