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Electronic interactions of i, i + 1 dithioamides: increased fluorescence quenching and evidence for n-to-?* interactions.

ABSTRACT: Thioamide residues can be effective, minimally-perturbing fluorescence quenching probes for studying protein folding and proteolysis. In order to increase the level of quenching, we have here explored the use of adjacent dithioamides. We have found that they are more effective fluorescence quenchers, as expected, but we have also observed unexpected changes in the thioamide absorption spectra that may arise from n-to-?* interactions of the thiocarbonyls. We have made use of the increased quenching to improve the fluorescence turn-on of thioamide protease sensors.

SUBMITTER: Huang Y

PROVIDER: S-EPMC4924517 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Electronic interactions of i, i + 1 dithioamides: increased fluorescence quenching and evidence for n-to-π* interactions.

Huang Yun Y Ferrie John J JJ Chen Xing X Zhang Yitao Y Szantai-Kis D Miklos DM Chenoweth David M DM Petersson E James EJ

Chemical communications (Cambridge, England) 20160601 50

Thioamide residues can be effective, minimally-perturbing fluorescence quenching probes for studying protein folding and proteolysis. In order to increase the level of quenching, we have here explored the use of adjacent dithioamides. We have found that they are more effective fluorescence quenchers, as expected, but we have also observed unexpected changes in the thioamide absorption spectra that may arise from n-to-π* interactions of the thiocarbonyls. We have made use of the increased quenchi ...[more]

PMID: 27229876

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