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Azido Homoalanine is a Useful Infrared Probe for Monitoring Local Electrostatistics and Sidechain Solvation in Proteins.

ABSTRACT: The use of IR probes to monitor protein structure, deduce local electric field, and investigate the mechanism of enzyme catalysis and protein folding has attracted increasing attention. Here, the azidohomoalanine (Aha) is considered as a useful IR probe. The intricate details of the distinct effects of backbone peptide bonds and H-bonded water molecules on the azido stretch mode of the IR probe Aha were revealed by carrying out QM/MM MD simulations of two variants of the protein NTL9, NTL9-Met1Aha and NTL9-Ile4Aha and comparing the resulting simulated IR spectra with experiments.

SUBMITTER: Choi JH

PROVIDER: S-EPMC3290331 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Azido Homoalanine is a Useful Infrared Probe for Monitoring Local Electrostatistics and Sidechain Solvation in Proteins.

Choi Jun-Ho JH Raleigh Daniel D Cho Minhaeng M

The journal of physical chemistry letters 20110901 17

The use of IR probes to monitor protein structure, deduce local electric field, and investigate the mechanism of enzyme catalysis and protein folding has attracted increasing attention. Here, the azidohomoalanine (Aha) is considered as a useful IR probe. The intricate details of the distinct effects of backbone peptide bonds and H-bonded water molecules on the azido stretch mode of the IR probe Aha were revealed by carrying out QM/MM MD simulations of two variants of the protein NTL9, NTL9-Met1A ...[more]

PMID: 22389750

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