Lysosomal integral membrane protein-2 as a phospholipid receptor revealed by biophysical and cellular studies

Lysosomal integral membrane protein-2 (LIMP-2) is a glucocerebrosidase receptor, which is linked to kidney failure and other diseases. Here the authors show that LIMP-2 is also a phospholipid receptor and present the lipid-bound structure of the LIMP-2 luminal domain dimer and discuss its lipid trafficking mechanism

Covalent Enzyme Inhibition through Fluorosulfate Modification of a Noncatalytic Serine Residue

Irreversible enzyme inhibitors and covalent chemical biology probes often utilize the reaction of a protein cysteine residue with an appropriately positioned electrophile (<i>e.g.</i>, acrylamide) on the ligand template. However, cysteine residues are not always available for site-specific protein labeling, and therefore new approaches are needed to expand the toolkit of appropriate electrophiles (“warheads”) that target alternative amino acids. We previously described the rational targeting of tyrosine residues in the active site of a protein (the mRNA decapping scavenger enzyme, DcpS) using inhibitors armed with a sulfonyl fluoride electrophile. These inhibitors subsequently enabled the development of clickable probe technology to measure drug-target occupancy in live cells. Here we describe a fluorosulfate-containing inhibitor (aryl fluorosulfate probe (FS-p1)) with excellent chemical and metabolic stability that reacts selectively with a noncatalytic serine residue in the same active site of DcpS as confirmed by peptide mapping experiments. Our results suggest that noncatalytic serine targeting using fluorosulfate electrophilic warheads could be a suitable strategy for the development of covalent inhibitor drugs and chemical probes

Introduction of a Crystalline, Shelf-Stable Reagent for the Synthesis of Sulfur(VI) Fluorides

The design, synthesis, and application of [4-(acetylamino)­phenyl]­imidodisulfuryl difluoride (AISF), a shelf-stable, crystalline reagent for the synthesis of sulfur­(VI) fluorides, is described. The utility of AISF is demonstrated in the synthesis of a diverse array of aryl fluorosulfates and sulfamoyl fluorides under mild conditions. Additionally, a single-step preparation of AISF was developed that installed the bis­(fluorosulfonyl)­imide group on acetanilide utilizing an oxidative C–H functionalization protocol

The 2.0 Å crystal structure of the ERα ligand-binding domain complexed with lasofoxifene

Lasofoxifene is a new and potent selective estrogen receptor modulator (SERM). The structural basis of its interaction with the estrogen receptor has been investigated by crystallographic analysis of its complex with the ligand-binding domain of estrogen receptor α at a resolution of 2.0 Å. As with other SERMs, lasofoxifene diverts the receptor from its agonist-bound conformation by displacing the C-terminal AF-2 helix into the site at which the LXXLL motif of coactivator proteins would otherwise be able to bind. Lasofoxifene achieves this effect by occupying the space normally filled by residue Leu 540, as well as by modulating the conformation of residues of helix 11 (His 524, Leu 525). A well-defined salt bridge between lasofoxifene and Asp 351 suggests that charge neutralization in this region of the receptor may explain the some of the antiestrogenic effects of lasofoxifene. The results suggest general features of ERα/SERM recognition, and add a new dimension to efforts to rationalize differences between the biological activity profiles exhibited by these important pharmacological agents