Abstract: The invention pertains to the method of N-terminus Glycine tagged metal-free protein purification by selective labeling of N-terminus Gly containing proteins, its capture, and release through modified resin under mild operating conditions. The selective labeling of N-terminus Glycine enables the formation of an aminoalcohol. The invention is for selective tagging of N-Gly in a protein. The invention is for separation of immobilised N-terminus glycine proteins from the functionalised resin under mild aqueous physiological conditions by C—C bond dissociation with additive, in which the additive enables the resonance-assisted electron density (RED) polarization to facilitate C—C bond dissociation. The invention provides the N-Gly specific installation of a probe in a protein within cell lysate. The invention covers the special aldehydes, including its on-resin derivative, for the given purpose.

Abstract: A multifunctional chemical agents comprising functional agents Fn1, Fn2 and linkers, for the linchpin directed (LDM), protein directed (PDPM) modifications of proteins, and Fn1 accelerated kinetic labeling by Fn2.