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Updated: Jun 4, 2026

Synthesizing Amino Acids Modified with Reactive Carbonyls in Silico to Assess Structural Effects Using Molecular Dynamics Simulations
Published on: April 26, 2024
The stability of Cα peptide radicals: why glycyl radical enzymes?
Johnny Hioe1, Gökcen Savasci, Harald Brand
1Department of Chemistry, LMU München, Butenandtstrasse 5-13, 81377 München, Germany.
Abstract:
The conformational space of dipeptide models derived from glycine, alanine, phenylalanine, proline, tyrosine, and cysteine has been searched extensively and compared with the corresponding C(α) dipeptide radicals at the G3(MP2)-RAD level of theory. The results indicate that the (least-substituted) glycine dipeptide radical is the thermochemically most stable of these species. Analysis of the structural parameters indicates that this is due to repulsive interactions between the C(α) substituents and peptide units in the radical. A comparison of the conformational preferences of dipeptide radicals and their closed-shell parents also indicates that radical stability is a strongly conformation-dependent property.
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