Determination of deuterium-labeled tryptophan in proteins by means of high-performance liquid chromatography and thermospray mass spectrometry |
| |
| Authors: | E Karnaukhova W M Niessen U R Tjaden J Raap J Lugtenburg J van der Greef |
| |
| Institution: | Department of Organic Chemistry, Leiden University, The Netherlands. |
| |
| Abstract: | In order to develop direct methods for determining the extent of metabolic incorporation of isotopically labeled amino acids into a protein, the determination of deuterated tryptophan in 2H5]tryptophan-bacteriorhodopsin was investigated. The isotopically modified protein was subjected to alkaline hydrolysis. After phenyl isothiocyanate derivatization of the hydrolysate, the mixture was separated by reversed-phase liquid chromatography. Field desorption mass spectrometry and thermospray mass spectrometry were investigated for their ability to determine the ratio between 2H5]tryptophan and total tryptophan in the collected fractions. In order to check the procedure a set of known tryptophan/2H5]tryptophan mixtures were passed through the same derivatization, HPLC separation, and lyophilization procedure as used for the biological samples. |
| |
| Keywords: | |
|
|
