Toward a Biorelevant Structure of Protein Kinase C Bound Modulators: Design, Synthesis, and Evaluation of Labeled Bryostatin Analogs for Analysis with REDOR NMR Spectroscopy.
Toward a Biorelevant Structure of Protein Kinase C Bound Modulators: Design, Synthesis, and Evaluation of Labeled Bryostatin Analogs for Analysis with REDOR NMR Spectroscopy.
J Am Chem Soc. 2015 Feb 24;
Authors: Loy BA, Lesser AB, Staveness D, Billingsley KL, Cegelski L, Wender PA
Abstract
Protein kinase C (PKC) modulators are currently of great importance in preclinical and clinical studies directed at cancer, immunotherapy, HIV eradication, and Alzheimer's disease. However, the bound conformation of PKC modulators in a membrane environment is not known. Rotational Echo Double Resonance (REDOR) NMR spectroscopy could uniquely address this challenge. However, REDOR NMR requires strategically-labeled, high affinity ligands to determine inter-label distances from which the conformation of the bound ligand in the PKC-ligand complex could be identified. Here we report the first computer-guided design and syntheses of three bryostatin analogs strategically-labeled for REDOR NMR analysis. Extensive computer analyses of energetically-accessible analog conformations suggested preferred labeling sites for the identification of the PKC-bound conformers. Significantly, three labeled analogs were synthesized, and, as required for REDOR analysis, all proved highly potent with PKC affinities (~1 nM) on par with bryostatin. These potent and strategically-labeled bryostatin analogs are new structural leads and provide the necessary starting point for projected efforts to determine the PKC-bound conformation of such analogs in a membrane environment, as needed to design new PKC modulators and understand PKC-ligand-membrane structure and dynamics.
PMID: 25710634 [PubMed - as supplied by publisher]
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