Purification and properties of the B component of Escherichia coli tryptophan synthetase.
نویسندگان
چکیده
The B subunit can catalyze Reaction 1 even in the absence of Subunit A (5). Reaction 2 can be catalyzed similarly by the A subunit alone (2). Both Reaction 1 and Reaction 2 proceed best, however, when catalyzed by the complex formed from the two subunits (2). Reaction 3 takes place only in the presence of the AB complex; apparently indole is not a free intermediate in this reaction (2). The A protein has been crystallized and well characterized (6-S). This communication describes the purification of the B protein, as well as some of its physical, chemical, and enzymatic properties.
منابع مشابه
The A protein of the tryptophan synthetase of Escherichia coli. Purification, crystallization, and composition studies.
Previous studies (2, 4) have led to the conclusion that Reaction 3 is probably the physiologically essential reaction in the biosynthesis of tryptophan in E. coli. Studies of the relationship between gene structure and protein structure which are presently being carried out with the A component of this system (5-8) have necessitated investigations of the properties, composition and primary stru...
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عنوان ژورنال:
- The Journal of biological chemistry
دوره 240 12 شماره
صفحات -
تاریخ انتشار 1965