A catalytic role for threonine-12 of E. coli asparaginase II as established by site-directed mutagenesis.
نویسندگان
چکیده
A threonine-12 to alanine mutant of E. coli asparaginase II (EC 3.5.1.1) has less than 0.01% of the activity of wild-type enzyme. Both tertiary and quaternary structure of the enzyme are essentially unaffected by the mutation; thus the activity loss seems to be the result of a direct impairment of catalytic function. As aspartate is still bound by the mutant enzyme, Thr-12 appears not be involved in substrate binding.
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عنوان ژورنال:
- FEBS letters
دوره 285 1 شماره
صفحات -
تاریخ انتشار 1991