Potential of polypeptide-based materials: from spider silk to gene delivery

Friday 3 November, 2017
Rountree Room 356, Level 3, Biological Sciences Building D26, UNSW Kensington Campus

High-performance biological materials in nature are mainly composed of amino acids. Polymer of amino acids, namely, polypeptide has therefore been recognized as bioactive and functional material, however, use of those biopolymers as structural materials is still challenging. One of the major drawbacks of polypeptide-based materials is their limited synthesis method. Dr Keiji Numata's research group has successfully synthesized various polypeptides, even with unnatural amino acids or nylon units, via chemo-enzymatic polymerization. Those artificial polypeptides containing unnatural units achieve several properties that cannot be done by natural polypeptides. This synthesis method provides a new insight for material design of polypeptide. Furthermore, the designed polypeptides can be used as structural materials like spider silks and as functional materials including gene carriers for gene therapy and organellar engineering in eukaryotes. In this seminar, the current progress on the materials design of polypeptide will be introduced and reviewed.


Dr Keiji Numata earned his Ph.D. (2007) with a thesis centered on enzymatic degradation and synthesis with hydrolases of biopolymers, especially poly(hydroxyalkanoate). His Ph.D. thesis includes works on enzymatic polymerization to synthesize branched biopolymers, which has been performed in Royal Institute of Technology (Sweden) under the supervisions of Prof Ann-Christine Albertsson and Associate Prof. Anna Finne-Wistrand. Dr. Numata worked as a JSPS Postdoctoral Fellow for Research Abroad at Tufts University (USA) where he studied biosynthesis of silk-based polymers via bacterial pathways as well as biomedical application of silk-based polymers to gene carriers in the laboratory of Stern Family Professor in Engineering David L. Kaplan. Dr. Numata moved to RIKEN as a Senior Scientist in 2010 to start up the Laboratory for Enzyme Research and also to investigate biosyntheses and material design of structural proteins, polypeptide and poly(amino acid). He has been a Team Leader (PI) of the lab since 2012 and Research Director, JST-ERATO Numata Organelle Reaction Cluster Project since 2016.