Carbonic anhydrase inhibitors. N-cyanomethylsulfonamides--a new zinc binding group in the design of inhibitors targeting cytosolic and membrane-anchored isoforms

Quantitative Characterization of Three Carbonic Anhydrase Inhibitors by LESA Mass Spectrometry

Liquid extraction surface analysis (LESA) coupled to native mass spectrometry (MS) presents unique analytical opportunities due to its sensitivity, speed, and automation. Here, we examine whether this tool can be used to quantitatively probe protein-ligand interactions through calculation of equilibrium dissociation constants (K_d values). We performed native LESA MS analyses for a well-characterized system comprising bovine carbonic anhydrase II and the ligands chlorothiazide, dansylamide, and sulfanilamide, and compared the results with those obtained from direct infusion mass spectrometry and surface plasmon resonance measurements. Two LESA approaches were considered: In one approach, the protein and ligand were premixed in solution before being deposited and dried onto a solid substrate for LESA sampling, and in the second, the protein alone was dried onto the substrate and the ligand was included in the LESA sampling solvent. Good agreement was found between the K_d values derived from direct infusion MS and LESA MS when the protein and ligand were premixed; however, K_d values determined from LESA MS measurements where the ligand was in the sampling solvent were inconsistent. Our results suggest that LESA MS is a suitable tool for quantitative analysis of protein-ligand interactions when the dried sample comprises both protein and ligand.

Discovery of Strecker-type α-aminonitriles as a new class of human carbonic anhydrase inhibitors using differential scanning fluorimetry

A new type of carbonic anhydrase inhibitors was identified via differential scanning fluorimetry (DSF) screening. The compounds displayed interesting inhibition profile against human carbonic anhydrase isoforms I, II, IX and XII with an obvious selectivity displayed by one compound toward carbonic anhydrase (CA) IX, an established anti-cancer target. A hypothetical mechanism of inhibitory action by the Strecker-type α-aminonitriles has been proposed.

RL. The PyRosetta Toolkit: a graphical user interface for the Rosetta software suite

The Rosetta Molecular Modeling suite is a command-line-only collection of applications that enable high-resolution modeling and design of proteins and other molecules. Although extremely useful, Rosetta can be difficult to learn for scientists with little computational or programming experience. To that end, we have created a Graphical User Interface (GUI) for Rosetta, called the PyRosetta Toolkit, for creating and running protocols in Rosetta for common molecular modeling and protein design tasks and for analyzing the results of Rosetta calculations. The program is highly extensible so that developers can add new protocols and analysis tools to the PyRosetta Toolkit GUI.