Diamond Seminar - Prof. Yoshihiro Ito
On Monday (27.06.2016, 10:00 am, MCB Seminar Room 3/14) in the Malopolska Centre of Biotechnology we will host Prof. Yoshihiro Ito.
Prof. Yoshihiro Ito
Chief Scientist and Director
Nano Medical Engineering Laboratory, RIKEN and Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako-shi, Saitama, Japan
Web site: http://www.riken.jp/nano-med.eng.lab/index_eng.html
Title: Peptide designs by evolutionary engineering and for self-assembly
Polypeptides and polynucleotides are programmable natural polymers whose linear sequences can be designed and synthesized by the cellular transcription/translation machinery and also by solid phase synthesis. Nature primarily uses proteins as the molecular machines and nucleic acids as the medium for the manipulation of heritable information. However, development of biotechnology has extended the original functions.
Molecular evolutionary engineering, in vitro selection is one of the strategies for extension of the original functions. This methodology was originally limited to selection from a random sequence library comprising natural components (four oligonucleotides or 20 amino acids). However, during two decades, the library has extended from a "natural soup" to an "unnatural soup". Unnatural oligonucleotides were incorporated into a selection library using enzymatic reactions. In addition, even in the peptide selection, incorporation of unnatural amino acids was achieved by the development of methods to synthesize misacylated tRNA and selection systems using a non-living system beyond phage display. The number of unnatural components incorporated in the selection library is increasing. Here some recent progress in peptide selections from a post-translationally modified library will be reported. By incorporation of azobenzene, fluorogenic group, and inhibitor, we succeeded in photo-responsive binding, fluorogenic, and highly inhibitory peptides, respectively.
Another strategy for extension is new nano-architectures using oligonucleotides and polypeptides. DNA nanotechnology uses orthogonal pairwise interacting modules of complementary nucleic acids as a strategy to construct defined complex 3D structures. Although the protein's tertiary structures are defined by multiple cooperative weak long-range interactions that have been optimized through evolution, the peptide was also designed for new nano-structures by self-assembly using coiled coil interactions. Here some new unique architectures of peptide self-assembly will be shown