The human glycine transporter 1 (GlyT1) regulates glycine-mediated neuronal excitation and inhibition through the sodium- and chloride-dependent reuptake of glycine. Inhibition of GlyT1 prolongs neurotransmitter signalling, and has long been a key strategy in the development of therapies for a broad range of disorders of the central nervous system, including schizophrenia and cognitive impairments. Here, using a synthetic single-domain antibody (sybody) and serial synchrotron crystallography, we have determined the structure of GlyT1 in complex with a benzoylpiperazine chemotype inhibitor at 3.
View Article and Find Full Text PDFOver the last decades, the use of heavy-chain-only antibodies has received growing attention in academia and industry as research and diagnostic tools as well as therapeutics. Their generation has improved with the help of innovative new methods such as the sybody technology; however, identifying conformation-selective compounds against membrane proteins remains a major challenge. In this chapter, we apply a thermal shift scintillation proximity assay (SPA-TS) to identify sybodies from an in vitro display campaign with the ability to selectively stabilize the inhibitor-bound conformation of the human solute carrier (SLC) family transporter SC6A9 (GlyT1).
View Article and Find Full Text PDFMechanistic and structural studies of membrane proteins require their stabilization in specific conformations. Single domain antibodies are potent reagents for this purpose, but their generation relies on immunizations, which impedes selections in the presence of ligands typically needed to populate defined conformational states. To overcome this key limitation, we developed an in vitro selection platform based on synthetic single domain antibodies named sybodies.
View Article and Find Full Text PDFVenom-derived peptide toxins can modify the gating characteristics of excitatory channels in neurons. How they bind and interfere with the flow of ions without directly blocking the ion permeation pathway remains elusive. Here we report the crystal structure of the trimeric chicken Acid-sensing ion channel 1 in complex with the highly selective gating modifier Psalmotoxin 1 at 3.
View Article and Find Full Text PDFThe lipophilic beta-lactone, lipstatin, inhibits pancreatic lipase and has been shown earlier to be biosynthesized by Claisen condensation of two fatty acid moieties. We present data from incorporation experiments with [U-13C6]leucine showing that a branched chain analogue of lipstatin is biosynthesized from leucine.
View Article and Find Full Text PDFThree putative intermediates in the biosynthesis of the lipase inhibitor lipstatin were synthesized in stable isotope-labeled form and were added to fermentation cultures of Streptomyces toxytricini. Biosynthetic lipstatin was isolated and analyzed by NMR spectroscopy. [3,10,11,12-(2)H]-(3S,5Z,8Z)-3-hydroxytetradeca-5,8-dienoic acid (9) was shown to serve as a direct biosynthetic precursor of lipstatin.
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