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Updated: Jun 27, 2025

Targeting Cysteine Thiols for in Vitro Site-specific Glycosylation of Recombinant Proteins
Published on: October 4, 2017
Impact of the Acetyl Group on Cysteine: A Study of N-Acetyl-Cysteine through Rotational Spectroscopy
S Mato1, S Municio1, J L Alonso1
1Grupo de Espectroscopia Molecular (GEM), Edificio Quifima Laboratorios de Espectroscopia y Bioespectroscopia, Parque Científico Universidad de Valladolid, 47011, Valladolid, Spain.
Abstract:
Herein, we report a spectroscopic study of N-acetyl-L-cysteine, an important antioxidant drug, using Fourier-transform microwave techniques and in isolated conditions. Two conformers are observed, where most stable structure adopts a cis disposition, and the second conformer has a lower abundance and adopts a trans disposition. The rotational constants and the barriers to methyl internal rotation are determined for each conformer, allowing a precise conformation identification. The results show that the cis form adopts an identical structure in the crystal, solution, and gas phases. Additionally, the structures are contrasted against those of cysteine.
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