Chemical proteomics of reactive molecules

Abstract The activity analysis of proteome-wide action of small reactive molecules infers their biological consequences and has a profound impact on human health. These analyses utilize and stimulate technological advances in chemical proteomics. This chapter primarily describes a new α-methylene-β-lactone (MeLac) alkyne probe (MeLacA) as a broadly reactive probe for chemical proteomics measurements. It discusses the reactivity of MeLacA in comparison with widely used iodoacetamide and fluorophosphonate probes. The use of probes of broad reactivity empowers adaptable competitive chemical proteomics platforms for subtractive analysis of proteome-wide reactions of small reactive molecules. The MeLac probe has multiple electrophilic sites. The probe MeLacA recruits glutathione in live cells to form a selective β-lactone probe, demonstrating a modular concept of rapidly developing highly selective chemical probes from an existing multi-electrophilic scaffold. This chapter concludes with some of our perspectives on chemical proteomics measurements and the promise of using scaffold probes to develop new covalent proteomics probes for precisely analyzing the proteome's activity domain within a zoomable scope.