TY - JOUR
T1 - Periodic introduction of aromatic units in polypeptides via chemoenzymatic polymerization to yield specific secondary structures with high thermal stability
AU - Tsuchiya, Kousuke
AU - Kurokawa, Naruki
AU - Gimenez-Dejoz, Joan
AU - Gudeangadi, Prashant G.
AU - Masunaga, Hiroyasu
AU - Numata, Keiji
N1 - Funding Information:
Acknowledgements The authors acknowledge Dr. Takaaki Hikima for his assistance and discussion on the WAXD experiments at BL45XU SPring-8, Harima, Japan. This work was financially supported by the RIKEN Engineering Network Project, Impulsing Paradigm Change through the Disruptive Technologies Program (ImPACT) and JSPS KAKENHI (Grant Number JP17K18361).
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Polypeptides containing periodic aromatic residues in their main chains were synthesized via papain-catalyzed chemoenzymatic polymerization of tripeptide ester monomers under moderate conditions in aqueous buffers. As the monomer, 4-aminobenzoic acid (Abz) was modified with Gly or Ala at the N- and C-termini to mitigate the poor substrate specificity of papain to unnatural amino acids. The tripeptide esters, namely, GlyAbzGly and AlaAbzAla ethyl esters, can be recognized and polymerized by papain, resulting in the polypeptides poly(GlyAbzGly) and poly(AlaAbzAla), respectively, with periodic sequences containing Abz units every three residues. Copolymerization of tripeptide esters with Gly or Ala ethyl ester also proceeded in the presence of papain. The secondary structures of the Abz-containing polypeptides were investigated by IR and wide-angle X-ray diffraction (WAXD) analysis. The WAXD profile of poly(GlyAbzGly) was similar to that of polyGly, whereas poly(AlaAbzAla) adopted a sheet-like structure similar to the β-sheet of polyAla. Thermal analysis of Abz-containing polypeptides revealed that the high thermal stability of the Abz-containing polypeptides is related to the distinct sequences that periodically include Abz residues.
AB - Polypeptides containing periodic aromatic residues in their main chains were synthesized via papain-catalyzed chemoenzymatic polymerization of tripeptide ester monomers under moderate conditions in aqueous buffers. As the monomer, 4-aminobenzoic acid (Abz) was modified with Gly or Ala at the N- and C-termini to mitigate the poor substrate specificity of papain to unnatural amino acids. The tripeptide esters, namely, GlyAbzGly and AlaAbzAla ethyl esters, can be recognized and polymerized by papain, resulting in the polypeptides poly(GlyAbzGly) and poly(AlaAbzAla), respectively, with periodic sequences containing Abz units every three residues. Copolymerization of tripeptide esters with Gly or Ala ethyl ester also proceeded in the presence of papain. The secondary structures of the Abz-containing polypeptides were investigated by IR and wide-angle X-ray diffraction (WAXD) analysis. The WAXD profile of poly(GlyAbzGly) was similar to that of polyGly, whereas poly(AlaAbzAla) adopted a sheet-like structure similar to the β-sheet of polyAla. Thermal analysis of Abz-containing polypeptides revealed that the high thermal stability of the Abz-containing polypeptides is related to the distinct sequences that periodically include Abz residues.
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U2 - 10.1038/s41428-019-0242-z
DO - 10.1038/s41428-019-0242-z
M3 - Article
AN - SCOPUS:85070083915
VL - 51
SP - 1287
EP - 1298
JO - Polymer Journal
JF - Polymer Journal
SN - 0032-3896
IS - 12
ER -