Mass spectrometry (MS) has become an important tool for high-throughput screening, owing to its ability to directly probe interactions between target proteins and ligands from the libraries of drug-like molecules. Screening by mass spectrometry, both covalent and non-covalent, includes several approaches with different areas of application. To address a growing demand of our drug discovery partners, MS-based Screening group has been established at Bienta in 2019.
Being a part of Enamine, the largest manufacturer of screening compounds for drug discovery, Bienta has gained experience in covalent screening by MS. Among the variety of the covalent probes, Cysteine-specific binders are of the highest demand. Our MS-based screening group is working with a list of Cysteine covalent fragments and screening compounds libraries, as well as custom compound selections from specific Cysteine-targeted warheads, such as acrylamides, chloroacetamides, vinyl sulfone compounds, and others. The libraries are being constantly updated, to ensure a novel and diverse chemical space for the quests for new hits.
Our team is equipped with two Agilent Q-TOF LC-MS systems dedicated for MS screening projects. A typical covalent screening project consists of 2 stages: (1) method development and (2) the screening per se, including hit confirmation and counterscreen. We mostly work with the libraries in 384-well plate format.
For the data analysis, our software team developed an in-house data parser which goes through MS peak lists from individual wells, searching for protein-ligand conjugate peaks, and calculates % of adduct formation. To satisfy all customers’ requests and answer additional questions that may arise during the screening, our MS-based Screening group can perform a variety of hit follow-up services, including diverse orthogonal screens, intrinsic reactivity, kinetic studies, and ligand binding localization studies.
At Bienta, MS-based Screening group works in close collaboration with the Recombinant Protein Expression group. Target proteins can be produced in E.coli, baculovirus or mammalian systems.