The oxidation state of copper in resting tyrosinase.
نویسندگان
چکیده
Resting tryosinase was diamagnetic between 1.4 K and 200 K. Redox titration showed that it, but not apotyrosinase, contained a titrable group, E’, = $0.36 volt (pH 7.0), R = 2. Upon denaturation with acid under strictly anaerobic conditions, the EPR-detectable copper increased from less than 5 % of the copper present to about 100%. It is concluded that the active site of the enzyme contains a pair of antiferromagnetically coupled Cu2+ ions.
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 249 19 شماره
صفحات -
تاریخ انتشار 1974