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Theoretical Study on the Mechanism of the Acylate Reaction of β-Lactamase.

ABSTRACT: Using density functional theory and a cluster approach, we study the reaction potential surface and compute Gibbs free energies for the acylate reaction of β-lactamase with penicillin G, where the solvent effect is important and taken into consideration. Two reaction paths are investigated: one is a multi-step process with a rate-limit energy barrier of 19.1 kcal/mol, which is relatively small, and the reaction can easily occur; the other is a one-step process with a barrier of 45.0 kcal/mol, which is large and thus makes the reaction hard to occur. The reason why the two paths have different barriers is explained.

SUBMITTER: Wei WM

PROVIDER: S-EPMC8154126 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Theoretical Study on the Mechanism of the Acylate Reaction of β-Lactamase.

Wei Wen-Mei WM Xu Yan-Li YL Zheng Ren-Hui RH Zhao Tingting T Fang Weijun W Qin Yi-De YD

ACS omega 20210507 19

Using density functional theory and a cluster approach, we study the reaction potential surface and compute Gibbs free energies for the acylate reaction of β-lactamase with penicillin G, where the solvent effect is important and taken into consideration. Two reaction paths are investigated: one is a multi-step process with a rate-limit energy barrier of 19.1 kcal/mol, which is relatively small, and the reaction can easily occur; the other is a one-step process with a barrier of 45.0 kcal/mol, wh ...[more]

PMID: 34056410

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