Advances in Research on Non-site-specific Determination of Amino Acids Racemization Modification in Proteins

D-amino acid residues of protein are mainly produced by amino acid racemization (AAR), which has been proved to be related to the occurrence and development of cataracts and other diseases. Common analytical methods of protein AAR modification include whole protein AAR analysis, site-specific AAR analysis and non-site-specific AAR analysis. Non-site-specific determination of AAR modification is very important for the comprehensive exploration of in vivo and in vitro protein AAR modification. It is also significant to evaluate the effects of AAR modification on protein function and clarify the relationship between major diseases and protein AAR. In this paper, the research progresses of analytical methods of non-site-specific AAR modification in recent years are reviewed, in comparison with whole protein AAR and site-specific AAR modification analysis. The prospect of the non-site-specific AAR analysis is also discussed.