Investigation of Specific Binding Proteins to Photoaffinity Linkers for Efficient Deconvolution of Target Protein

Photoaffinity-based target identification has received recent attention as an efficient research tool for chemical biology and drug discovery. The major obstacle of photoaffinity-based target identification is the nonspecific interaction between target identification probes and nontarget proteins. Consequently, the rational design of photoaffinity linkers has been spotlighted for successful target identification. These nonspecific interactions have been considered as random events, and therefore no systematic investigation has been conducted regarding nonspecific interactions between proteins and photoaffinity linkers. Herein, we report the protein-labeling analysis of photoaffinity linkers containing three photoactivatable moieties: benzophenone, diazirine, and arylazide. Each photoaffinity linker binds to a different set of proteins in a structure-dependent manner, in contrast to the previous conception. The list of proteins labeled by each photoaffinity linker was successfully used to eliminate the nonspecific binding proteins from target candidates, thereby increasing the success rate of target identification

Investigation of Specific Binding Proteins to Photoaffinity Linkers for Efficient Deconvolution of Target Protein

Photoaffinity-based target identification has received recent attention as an efficient research tool for chemical biology and drug discovery. The major obstacle of photoaffinity-based target identification is the nonspecific interaction between target identification probes and nontarget proteins. Consequently, the rational design of photoaffinity linkers has been spotlighted for successful target identification. These nonspecific interactions have been considered as random events, and therefore no systematic investigation has been conducted regarding nonspecific interactions between proteins and photoaffinity linkers. Herein, we report the protein-labeling analysis of photoaffinity linkers containing three photoactivatable moieties: benzophenone, diazirine, and arylazide. Each photoaffinity linker binds to a different set of proteins in a structure-dependent manner, in contrast to the previous conception. The list of proteins labeled by each photoaffinity linker was successfully used to eliminate the nonspecific binding proteins from target candidates, thereby increasing the success rate of target identification

Treatment of Sepsis Pathogenesis with High Mobility Group Box Protein 1‑Regulating Anti-inflammatory Agents

Sepsis is one of the major causes of death worldwide when associated with multiple organ failure. However, there is a critical lack of adequate sepsis therapies because of its diverse patterns of pathogenesis. The pro-inflammatory cytokine cascade mediates sepsis pathogenesis, and high mobility group box proteins (HMGBs) play an important role as late-stage cytokines. We previously reported the small-molecule modulator, inflachromene (<b>1d</b>), which inhibits the release of HMGBs and, thereby, reduces the production of pro-inflammatory cytokines. In this context, we intraperitoneally administered <b>1d</b> to a cecal ligation and puncture (CLP)-induced mouse model of sepsis and confirmed that it successfully ameliorated sepsis pathogenesis. On the basis of a structure–activity relationship study, we discovered new candidate compounds, <b>2j</b> and <b>2l</b>, with improved therapeutic efficacy in vivo. Therefore, our study clearly demonstrates that the regulation of HMGB1 release using small molecules is a promising strategy for the treatment of sepsis