Monovalent cation activation of tryptophanase.
نویسندگان
چکیده
منابع مشابه
Monovalent and Divalent Cation Permeation
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An improved purification of Escherichia coli K12 tryptophanase is presented. It is shown that the apoenzyme crystals, oxidized by exposure to air, can be reactivated by treatment with a reducing agent. The titration of sulfhydryl groups shows that four -SH groups are exposed end two are masked per protomer. The influence of two effecters, monovalent cations and the coenzyme pyridoxal S-phosphat...
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Pyruvate formate-lyase activating enzyme (PFL-AE) is a radical S-adenosyl-l-methionine (SAM) enzyme that installs a catalytically essential glycyl radical on pyruvate formate-lyase. We show that PFL-AE binds a catalytically essential monovalent cation at its active site, yet another parallel with B12 enzymes, and we characterize this cation site by a combination of structural, biochemical, and ...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1977
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(18)71835-8