title: Papain-Catalyzed Chemoenzymatic Synthesis of Telechelic Polypeptides Using Bis(Leucine Ethyl Ester) Initiator.
abstract: In order to construct unique polypeptide architectures, a novel telechelic-type initiator with two leucine ethyl ester units is designed for chemoenzymatic polymerization. Glycine or alanine ethyl ester is chemoenzymatically polymerized using papain in the presence of the initiator, and the propagation occurs at each leucine ethyl ester unit to produce the telechelic polypeptide. The formation of the telechelic polypeptides is confirmed by (1) H NMR and MALDI-TOF mass spectroscopies. It is revealed by AFM observation that long nanofibrils are formed from the telechelic polyalanine, whereas a conventional linear polyalanine with a similar degree of polymerization shows granule-like structures. The telechelic polyglycine and polyalanine show the crystalline structures of Polyglycine II and antiparallel β-sheet, respectively. It is demonstrated that this method to synthesize telechelic-type polypeptides potentially opens up a pathway to construct novel hierarchical structures by self-assembly.
authors.affiliation: Enzyme Research Team, Biomass Engineering Research Division, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
authors.forename: Kousuke
authors.initials: K
authors.lastname: Tsuchiya
authors.affiliation: Enzyme Research Team, Biomass Engineering Research Division, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Numata
mesh_terms: D002384:Catalysis; D004986:Ether / Q000737:chemistry; D007930:Leucine / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010206:Papain / Q000138:chemical synthesis / Q000737:chemistry*; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D058105:Polymerization; D011108:Polymers / Q000737:chemistry
chemical_list: D010455:Peptides; D011108:Polymers; D004986:Ether; C019529:polyalanine; D010206:Papain; D007930:Leucine
keywords: chemoenzymatic polymerization; papain; polyalanines; polyglycines; telechelic polymers