The primary structure of a protein contains the peptide bond (-CO-NH-), which has the ability to form hydrogen bonds and influence protein molecular shape. (a) If the force constant of N-H bonds in non-hydrogen bonded regions of a protein is 680 Nm?, predict the vibrational wavenumber value for non-hydrogen bonded N-H stretching in the infrared spectra of proteins. Show all working. (b) A hydrogen-bonded section of a protein produces a N-H stretching band at 3386 cm in the infrared spectrum. Determine the force constant for the hydrogen bonded N-H in the protein. Show all working. (c) Briefly describe how the presence of hydrogen bonding influences the N-H stretching mode of proteins.

The primary structure of a protein contains the peptide bond (-CO-NH-), which has the ability to form hydrogen bonds and influence protein molecular shape. (a) If the force constant of N-H bonds in non-hydrogen bonded regions of a protein is 680 Nm?, predict the vibrational wavenumber value for non-hydrogen bonded N-H stretching in the infrared spectra of proteins. Show all working. (b) A hydrogen-bonded section of a protein produces a N-H stretching band at 3386 cm in the infrared spectrum. Determine the force constant for the hydrogen bonded N-H in the protein. Show all working. (c) Briefly describe how the presence of hydrogen bonding influences the N-H stretching mode of proteins.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter18: Raman Spectroscopy

Section: Chapter Questions

Problem 18.9QAP

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