Peptide Ligation Technology

What are peptide ligases?

Peptide ligases are enzymes that naturally function as both molecular scissors and glue for multiple protein engineering applications. Our suite of plant-derived peptide ligases are made in the laboratory, and can be used for multiple applications, including:

  • Stabilising pharmaceuticals by creating circular peptides
  • Site-specific labelling of peptides or proteins
  • Creation of modular proteins

What are the advantages of our peptide ligases?

These enzymes are next generation, best-in-class tools for biotechnology. They offer excellent efficiency, broad effectiveness and a small non-native footprint. Fast reactions and limited side products mean that yields approaching 100% can be achieved within minutes using very small amounts of enzyme.

Rapid and efficient

10 minute reactions or less are possible. Limited or no side products evident

Broadly effective

Peptides of different structures and sizes can be targeted

Limited foreign residues

Target can be modified with little change to its original composition.

Economical

Approximately 2000-times less enzyme than target can be used

Examples of peptide ligase use

Stabilising pharmaceuticals by creating circular peptides

Cyclisation is a challenging modification to achieve by other methods, but our enzymes offer rapid and simple cyclic peptide production in around 10 minutes. The use of our enzymes to cyclise peptides can create a product with more drug-like properties such as:

  • increased potency
  • oral availability
  • increased stability

Image: Enzyme recognition residues were added to a target peptide. Hexima’s peptide ligases could rapidly convert the linear peptide to its circular form.

Site-specific labelling of peptides or proteins

Traditional methods of peptide labelling, for example with fluorescent groups, typically don’t allow control over the position or number of labels incorporated. Our enzymatic approach can specifically label either end of a target peptide and only one label is incorporated per molecule.

A high degree of labelling (>87%) in 30 min is routinely achievable and the labelled product can be easily separated from any unlabelled material.

Image: Enzyme recognition residues were added to an anti-fungal target peptide and a fluorescent tag. Hexima’s peptide ligases could rapidly link the fluorescent tag to the C-terminus of the target peptide. The labelled peptide could then be used in microscopy to visualise binding to fungal cells.

Creation of modular proteins

Proteins often consist of multiple domains with different functions. Our enzymes allow different domains to be joined together after peptide or protein synthesis. This “plug-and-play” approach provides flexibility to the creation of new, multi-functional polypeptides. For example, our peptide ligases can create bi-functional molecules by combining two different anti-microbial peptides.

Image: Enzyme recognition residues were added to two target peptides. Hexima’s peptide ligases could rapidly link the two peptides, creating a larger, bi-functional molecule.