ABSTRACT
Protein-templated fragment ligations have been established as a powerful method for the assembly and detection of optimized protein ligands. Initially developed for reversible ligations, the method has been expanded to irreversible reactions enabling the formation of super-additive fragment combinations. Here, protein-induced Mannich ligations are discovered as a biocatalytic reaction furnishing inhibitors of the transcription factor STAT5. STAT5 protein catalyzes multicomponent reactions of a phosphate mimetic, formaldehyde, and 1H-tetrazoles yielding protein ligands with greatly increased binding affinity and ligand efficiency. Reactions are induced under physiological conditions selectively by native STAT5 but not by other proteins. Formation of ligation products and (auto-)inhibition of the reaction are quantified and the mechanism is investigated. Inhibitors assembled by STAT5 block specifically the phosphorylation of this protein in a cellular model of acute myeloid leukemia (AML), DNA-binding of STAT5 dimers, expression of downstream targets of the transcription factor, and the proliferation of cancer cells in mice.
Subject(s)
Antineoplastic Agents/chemical synthesis , Biocatalysis , Leukemia, Myeloid, Acute/drug therapy , STAT5 Transcription Factor/chemistry , Tumor Suppressor Proteins/chemistry , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Cell Proliferation/drug effects , DNA/metabolism , Drug Development/methods , Humans , Ligands , Mice , Mice, Inbred NOD , Molecular Docking Simulation , Phosphorylation/drug effects , STAT5 Transcription Factor/antagonists & inhibitors , STAT5 Transcription Factor/metabolism , Tumor Suppressor Proteins/antagonists & inhibitors , Tumor Suppressor Proteins/metabolism , Xenograft Model Antitumor AssaysABSTRACT
Only three steps are required for the convenient synthesis of 2-C-branched glyco-amino acids from glycals with good yields and stereoselectivities.
