Protein post-translational modifications - A challenge for bioelectrochemistry

Post-translational modifications (PTMs) occur during or after protein biosynthesis under the action of various specific enzymes or reactive oxygen and nitrogen species. These modifications affect a wide range of protein characteristics such as the size and charge of proteins, their activation state, enzymatic activity, cellular localization, interacting partners, and life cycle. Imbalance in protein PTMs can lead to a development of various diseases, among them are cancer and diabetes. It is also generally accepted that protein PTMs, namely glycation and oxidation, play a role in aging. Changing physical and chemical properties of protein molecules, PTMs can eventually alter their electrochemical behavior. This review presents a practical guide for electrochemists and other analytical chemists by summarizing classical and modern biochemical data regarding protein PTMs. A special attention is paid to known modifications in electrochemically active amino acids, which are promising for direct electroanalysis. The well-established and emerging approaches to electrochemical detection of protein PTMs are considered in details. The perspectives of direct electrochemical analysis of protein PTMs based on structural features of modifications of amino acid residues are discussed. (C) 2019 Elsevier B.V. All rights reserved.