Fructosebisphosphatase isoenzymes of the chemoautotroph Xanthobacter flavus.
نویسندگان
چکیده
Xanthobacter flavus employs two fructosebisphosphatase (FBPase)-sedoheptulosebisphosphatase (SBPase) enzymes. One of these is constitutively expressed and has a high FBPase-to-SBPase ratio. The alternative enzyme, which is encoded by cbbF, is induced during autotrophic growth. The cbbF gene was expressed in Escherichia coli, and the FBPase was purified to homogeneity. The purified enzyme has a specific FBPase activity of 114 mumol/min/mg of protein, a Michaelis constant for fructosebisphosphate of 3 microM, and a low FBPase-to-SBPase ratio. CbbF was activated by ATP and inhibited by Ca2+.
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عنوان ژورنال:
- Journal of bacteriology
دوره 177 20 شماره
صفحات -
تاریخ انتشار 1995