Protein Chemical Modification Using Highly Reactive Species and Spatial Control of Catalytic Reactions

Abstract

Protein bioconjugation has become an increasingly important research method for introducing artificial functions in to protein with various applications, including therapeutics and biomaterials. Due to its amphiphilic nature, only a few tyrosine residues are exposed on the protein surface. Therefore, tyrosine residue has attracted attention as suitable targets for site-specific modification, and it is the most studied amino acid residue for modification reactions other than lysine and cysteine residues. In this review, we present the progress of our tyrosine chemical modification studies over the past decade. We have developed several different catalytic approaches to selectively modify tyrosine residues using peroxidase, laccase, hemin, and ruthenium photocatalysts. In addition to modifying tyrosine residues by generating radical species through single-electron transfer, we have developed a histidine modification method that utilizes singlet oxygen generated by photosensitizers. These highly reactive chemical species selectively modify proteins in close proximity to the enzyme/catalyst. Taking advantage of the spatially controllable reaction fields, we have developed novel methods for site-specific antibody modification, detecting hotspots of oxidative stress, and target identification of bioactive molecules.

Scale-Up Synthesis of Site-Specific Antibody–Drug Conjugates Using AJICAP Second-Generation Technology

“…To overcome the heterogeneity drawback of current ADCs, several site-specific and chemical conjugation methodologies have emerged in recent decades. , Utilizing Fc-affinity binders is a promising approach for the construction of site-specific ADCs . This novel conjugation method offers several advantages, such as not requiring antibody engineering and avoiding the use of enzymes, which can be challenging to remove after conjugation. − However, as this technology is mainly used at the research stage, the challenge of developing scalable and robust manufacturing processes using Fc-affinity reagents remains. The limited scope of Fc-affinity technologies for site-specific ADC generation prompted us to develop a versatile and facile direct antibody modification technology that circumvents antibody engineering .…”

Mechanism of ultrasonic combined with different fields on protein complex system and its effect on its functional characteristics and application: A review

“…Due to the modification of protein complex system by ultrasound is random and extensive, when the protein complex system is subjected to specific treatment, it is often compounded with chemical field and biological field, because the directional modification ability of chemical field and biological field will be stronger. For example: Sato [35] reviewed the research progress of chemical modification of tyrosine, a method of modifying histidine by singlet oxygen produced by photosensitizer has been developed, which has been proved to be highly selective. Similar to enzyme reaction, enzyme as a protein molecule participates in the modification process of protein composite system.…”