Recombinant histones are highly purified, bacterially- or eukaryotically-expressed histone proteins (H1, H2A, H2B, H3, H4 and their variants) produced using recombinant DNA technology. They provide consistent, well-characterized material for biochemical, structural, epigenetic, and assay development applications where native histone isolation is impractical or where site-specific modifications or sequence variants are required. Recombinant histones are available as individual proteins, defined combinations such as histone octamers, or engineered variants containing point mutations, epitope tags, truncations, and defined post-translational modifications (PTMs).

Key Features

• High Purity: Purified using chromatographic techniques including ion-exchange chromatography, reverse-phase HPLC, and optimized refolding procedures. Purity levels typically exceed 95% and are verified by SDS-PAGE and mass spectrometry.
• Sequence Fidelity: Available as canonical wild-type histones as well as numerous variants and isoforms, including H3.1, H3.3, H2A.Z, and macroH2A.
• Defined Assemblies: Available as recombinant histone octamers, nucleosome core particles (NCPs), and nucleosome arrays assembled under controlled refolding and salt conditions.
• Quality Control: Comprehensive lot-specific quality control may include SDS-PAGE analysis, intact mass spectrometry, peptide mapping, DNA-binding assays, and octamer assembly validation.

Common Applications

• Chromatin Reconstitution: Assembly of mononucleosomes and nucleosome arrays for biophysical characterization and structural studies using electron microscopy (EM), cryo-EM, and X-ray crystallography.
• Enzymatic Assays: Ideal substrates for histone-modifying enzymes including histone acetyltransferases (HATs), histone deacetylases (HDACs), histone methyltransferases (HMTs), demethylases, kinases, and ubiquitin ligases, enabling kinetic and IC₅₀ studies.
• Antibody Validation: Reference materials for evaluating the specificity and selectivity of PTM-specific antibodies through Western blotting, dot blotting, and peptide-array assays.
• Epigenetics Research: Investigation of chromatin readers, writers, erasers, and remodeling complexes using histones carrying precisely defined PTMs and sequence variants.
• Biophysical Analysis: Studies of DNA-histone interactions, nucleosome stability, salt-dependent remodeling, FRET-based assays, and single-molecule experiments.
• Assay Development and Screening: Development of high-throughput screening platforms for identifying inhibitors and modulators of histone-modifying enzymes and chromatin regulatory proteins.
• Structural Biology: Generation of homogeneous nucleosome preparations for cryo-EM and crystallographic analyses using defined histone sequences and modifications.