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Water-Soluble Polypeptides with Elongated, Charged Side Chains Adopt Ultra-Stable Helical Conformations.

ABSTRACT: Water-soluble polypeptides adopting ?-helical conformations with unprecedented high helicities were obtained by elongating the charge-containing side chains of the constituent amino acids to allow the terminal charges to be situated distally from the peptide backbone. Poly(?-(4-aminoethylthiopropoxyl)-benzyl-(L)-glutamate) (PAOBLG-AET) with a charge-peptide backbone distance of 17 ?-bonds exhibited a remarkably high helical content (81%) at a degree of polymerization as low as 10. The helical conformations of these short polypeptides were very stable against various harsh, protein-denaturing conditions, such as extreme pH, high temperature, and high salt or urea concentrations.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC3204311 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Water-Soluble Polypeptides with Elongated, Charged Side Chains Adopt Ultra-Stable Helical Conformations.

Zhang Yanfeng Y Lu Hua H Lin Yao Y Cheng Jianjun J

Macromolecules 20110901 17

Water-soluble polypeptides adopting α-helical conformations with unprecedented high helicities were obtained by elongating the charge-containing side chains of the constituent amino acids to allow the terminal charges to be situated distally from the peptide backbone. Poly(γ-(4-aminoethylthiopropoxyl)-benzyl-(L)-glutamate) (PAOBLG-AET) with a charge-peptide backbone distance of 17 σ-bonds exhibited a remarkably high helical content (81%) at a degree of polymerization as low as 10. The helical co ...[more]

PMID: 22049249

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