Tryptophan absorbs at a maximum wavelength of 280 nm. In a cuvette (1 cm-optical path length), a 200 µM tryptophan solution shows an absorbance value at 280 nm of 1.2. 1- Calculate & the molar absorption coefficient (also called molar extinction coefficient) of tryptophan. A solution of protein X, at the concentration of 25 µM, shows an absorbance value at 280 nm of 0.6. The protein X has no tyrosine and no phenylalanine residues. 2- Determine the number of tryptophan residues of the protein X.

Tryptophan absorbs at a maximum wavelength of 280 nm. In a cuvette (1 cm-optical path length), a 200 µM tryptophan solution shows an absorbance value at 280 nm of 1.2. 1- Calculate & the molar absorption coefficient (also called molar extinction coefficient) of tryptophan. A solution of protein X, at the concentration of 25 µM, shows an absorbance value at 280 nm of 0.6. The protein X has no tyrosine and no phenylalanine residues. 2- Determine the number of tryptophan residues of the protein X.

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

Chapter12: Atomic X-ray Spectrometry

Section: Chapter Questions

Problem 12.8QAP

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