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Self-assembling small molecules form nanofibrils that bind procaspase-3 to promote activation.

ABSTRACT: Modulating enzyme function with small-molecule activators, as opposed to inhibitors, offers new opportunities for drug discovery and allosteric regulation. We previously identified a compound, called 1541, from a high-throughput screen (HTS) that stimulates activation of a proenzyme, procaspase-3, to generate mature caspase-3. Here we further investigate the mechanism of activation and report the surprising finding that 1541 self-assembles into nanofibrils exceeding 1 ?m in length. These particles are an unanticipated outcome from an HTS that have properties distinct from standard globular protein aggregators. Moreover, 1541 nanofibrils function as a unique biocatalytic material that activates procaspase-3 via induced proximity. These studies demonstrate a novel approach for proenzyme activation through binding to fibrils, which may mimic how procaspases are naturally processed on protein scaffolds.

SUBMITTER: Zorn JA

PROVIDER: S-EPMC3253528 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Self-assembling small molecules form nanofibrils that bind procaspase-3 to promote activation.

Zorn Julie A JA Wille Holger H Wolan Dennis W DW Wells James A JA

Journal of the American Chemical Society 20111117 49

Modulating enzyme function with small-molecule activators, as opposed to inhibitors, offers new opportunities for drug discovery and allosteric regulation. We previously identified a compound, called 1541, from a high-throughput screen (HTS) that stimulates activation of a proenzyme, procaspase-3, to generate mature caspase-3. Here we further investigate the mechanism of activation and report the surprising finding that 1541 self-assembles into nanofibrils exceeding 1 μm in length. These particl ...[more]

PMID: 22066605

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