Conjugation site analysis of antibody-drug-conjugates (ADCs) by signature ion fingerprinting and normalized area quantitation approach using nano-liquid chromatography coupled to high resolution mass spectrometry.

Trastuzumab-MCC-DM1 (T-DM1) is an antibody-drug conjugate (ADC) that consists of a monoclonal antibody (mAb) trastuzumab non-cleavably linked to a cytotoxic drug DM1. During production, the DM1 agents were conjugated to the lysine residues of the mAb in a non-specific manner, yielding a heterogeneous mixture of ADC molecules that differ with respect to both the number and the conjugation sites of DM1 per mAb molecule. Since drug conjugation sites of ADC can significantly impact properties such as stability and pharmacokinetic behaviors, a rapid and reliable approach for conjugation site analysis of ADCs is highly demanded.

Glycerol-3-phosphate acyltransferase 6 (GPAT6) is important for tapetum development in Arabidopsis and plays multiple roles in plant fertility.

Glycerol-3-phosphate acyltransferase (GPAT) mediates the initial synthetic step for the formation of glycerolipids, which act as the major components of biological membranes and the principal stored forms of energy. GPAT6 is a member of the Arabidopsis GPAT family, which is crucial for cutin biosynthesis in sepals and petals. In this work, a functional analysis of GPAT6 in anther development and plant fertility was performed.