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Calibrated Calculation of Polyalanine Fractional Helicities from Circular Dichroism Ellipticities^†

Gabriel E. Job

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

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Björn Heitmann Dr.,

Björn Heitmann Dr.

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

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Robert J. Kennedy Dr.,

Robert J. Kennedy Dr.

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

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Sharon M. Walker Dr.,

Sharon M. Walker Dr.

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

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Daniel S. Kemp Prof.,

Daniel S. Kemp Prof.

[email protected]

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

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Gabriel E. Job,

Gabriel E. Job

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

Search for more papers by this author

Björn Heitmann Dr.,

Björn Heitmann Dr.

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

Search for more papers by this author

Robert J. Kennedy Dr.,

Robert J. Kennedy Dr.

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

Search for more papers by this author

Sharon M. Walker Dr.,

Sharon M. Walker Dr.

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

Search for more papers by this author

Daniel S. Kemp Prof.,

Daniel S. Kemp Prof.

[email protected]

Department of Chemistry, Room 18-296, Massachusetts Institute of Technology, Cambridge, MA 02139, USA, Fax: (+1) 617-258-7500

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First published: 20 October 2004

https://doi.org/10.1002/anie.200460536

Citations: 15

^†

This research was supported by the NSF CHE-0131250 and the NIH GM 13453 (S.M.W.).

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Graphical Abstract

Maximally helical polyalanines, 9 to 24 residues in length, are used to calibrate the assignment of fractional helicity (FH) from circular dichroism ellipticities. Water-solubilizing, helix-stabilizing N- and C-caps induce FHs>0.9 in core polyalanine regions. Linear length regressions of peptide molar ellipticities (blue-green curves) yield slopes (red arrows) that define molar per-residue ellipticities of a fully helical alanine residue (red curve).

Supporting Information

References

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October 25, 2004

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Calibrated Calculation of Polyalanine Fractional Helicities from Circular Dichroism Ellipticities^†

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Calibrated Calculation of Polyalanine Fractional Helicities from Circular Dichroism Ellipticities†

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Calibrated Calculation of Polyalanine Fractional Helicities from Circular Dichroism Ellipticities^†