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Distinctive circular dichroism signature for 14-helix-bundle formation by beta-peptides.

ABSTRACT: We identify a distinctive circular dichroism (CD) signature for self-assembled 14-helical beta-peptides. Our data show that self-assembly leads to a mimimum at 205 nm, which is distinct from the well-known minimum at 214 nm for a monomeric 14-helix. The onset of assembly is indicated by [theta]205/[theta]214>0.7. Our results will facilitate rapid screening for self-assembling beta-peptides and raise the possibility that far-UV CD will be useful for detecting higher-order structure for other well-folded oligoamide backbones.

SUBMITTER: Pomerantz WC

PROVIDER: S-EPMC2886586 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Distinctive circular dichroism signature for 14-helix-bundle formation by beta-peptides.

Pomerantz William C WC Grygiel Tami L R TL Lai Jonathan R JR Gellman Samuel H SH

Organic letters 20080409 9

We identify a distinctive circular dichroism (CD) signature for self-assembled 14-helical beta-peptides. Our data show that self-assembly leads to a mimimum at 205 nm, which is distinct from the well-known minimum at 214 nm for a monomeric 14-helix. The onset of assembly is indicated by [theta]205/[theta]214>0.7. Our results will facilitate rapid screening for self-assembling beta-peptides and raise the possibility that far-UV CD will be useful for detecting higher-order structure for other well ...[more]

PMID: 18396884

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