Interaction of the mechanism-based inactivator acetylene with ammonia monooxygenase of Nitrosomonas europaea.
نویسندگان
چکیده
The ammonia monooxygenase (AMO) of Nitrosomonas europaea is a metalloenzyme that catalyses the oxidation of ammonia to hydroxylamine. We have identified histidine 191 of AmoA as the binding site for the oxidized mechanism-based inactivator acetylene. Binding of acetylene changed the molecular mass of His-191 from 155.15 to 197.2 Da (+42.05), providing evidence that acetylene was oxidized to ketene (CH2CO; 42.04 Da) which binds specifically to His-191. It must be assumed that His-191 is part of the acetylene-activating site in AMO or at least directly neighbours this site.
منابع مشابه
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عنوان ژورنال:
- Microbiology
دوره 155 Pt 1 شماره
صفحات -
تاریخ انتشار 2009