Structural and Mechanistic Studies of Mofegiline Inhibition of Recombinant Human Monoamine Oxidase B

详细信息    查看全文

• 作者：Erika M. Milczek ; Daniele Bonivento ; Claudia Binda ; Andrea Mattevi ; Ian A. McDonald ; Dale E. Edmondson
• 刊名：Journal of Medicinal Chemistry
• 出版年：2008
• 出版时间：December 25, 2008
• 年：2008
• 卷：51
• 期：24
• 页码：8019-8026
• 全文大小：363K
• 年卷期：v.51,no.24(December 25, 2008)
• ISSN：1520-4804

文摘

Mechanistic and structural studies have been carried out to investigate the molecular basis for the irreversible inhibition of human MAO-B by mofegiline. Competitive inhibition with substrate shows an apparent K_i of 28 nM. Irreversible inhibition of MAO-B occurs with a 1:1 molar stoichiometry with no observable catalytic turnover. The absorption spectral properties of mofegiline inhibited MAO-B show features (λ_max 450 nm) unlike those of traditional flavin N(5) or C(4a) adducts. Visible and near-UV circular dichroism spectra of the mofegiline−MAO-B adduct shows a negative peak at 340 nm with an intensity similar to that of N(5) flavocyanine adducts. The X-ray crystal structure of the mofegiline−MAO-B adduct shows a covalent bond between the flavin cofactor N(5) with the distal allylamine carbon atom as well as the absence of the fluorine atom. A mechanism to explain these structural and spectral data is proposed.