Almac

The recombinant protein of interest is expressed as an N-terminal intein fusion protein. The properties of the intein domain are such that it induces an N to S acyl shift at this protein-intein junction to form the thioester intermediate.

This thioester intermediate is chemically cleaved under aqueous buffered conditions using hydrazine or dioxyamine to liberate the corresponding C-terminal hydrazide and aminoxy derivatives of the target protein.

The C-terminal derivatives chemoselectively react with ketone or aldehyde containing moieties (benzaldehyde PEG shown here) resulting in site specific C-terminal modification of the recombinant protein via stabilized hydrazone or oxime linkage.

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Key advantages of our technology

• Targeted, site specific ligation at the C-terminus – allows total control over the ligation process
• Retained biological activity – has the potential to improve upon the native protein i.e. by extending half life while maintaining the activity
• Robust, high yielding conjugation technology
• Mono conjugated species – COGs savings and lower dosing potential
• Conjugate equivalents ratio – low ratio equates to savings on COGs
• Compatible with disulphide-bond containing proteins
• Applicable to a wide range of labels and modifications
• Single modification site means homogeneous products produced