active site allosteric regulation antiviral drug biomining biomolecule carcinogen cell culture cell membrane chemical compound microarray chemogenomics cyclopamine dietary supplement digital object identifier drug drug design enzyme inhibitor gene expression ginkgo growth medium hhip insulin islets of langerhans medicine mesoderm molecular biology nonribosomal peptide organic compound peptidomimetic pharmacology phenols polyketide polymer prodrug protein protein kinase c retinoic acid secondary metabolite sonic hedgehog streptomyces