The effects of alpha-helical structure and cyanylated cysteine on each other.

ABSTRACT: Beta-thiocyanatoalanine, or cyanylated cysteine, is an artificial amino acid that can be introduced at solvent-exposed cysteine residues in proteins via chemical modification. Its facile post-translational synthesis means that it may find broad use in large protein systems as a probe of site-specific structure and dynamics. The C[triple bond]N stretching vibration of this artificial side chain provides an isolated infrared chromophore. To test both the perturbative effect of this side chain on local secondary structure and its sensitivity to structural changes, three variants of a model water-soluble alanine-repeat helix were synthesized containing cyanylated cysteine at different sites. The cyanylated cysteine side chain is shown to destabilize, but not completely disrupt, the helical str

SUBMITTER: Edelstein L 

PROVIDER: S-EPMC2851192 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature