In bacteria, isocitrate dehydrogenase is regulated by phosphorylation of a specific Ser residue in the enzyme active site. X-raystructures of the phosphorylated and the nonphosphorylated enzyme show no significant conformational differences. How doesphosphorylation regulate isocitrate dehydrogenase activity?O The phosphoryl group sterically hinders the substrate.O The phosphorylation bears a negative charge, which repels the substrate.O The phosphoryl group attracts positively charged Ca2* cations, which block the active site on the enzyme.None of the above.

1st option is correct The phosphoryl group sterically hinder the substrate. Because phosphorylation…

Answered: In bacteria, isocitrate dehydrogenase…

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter18: Glycolysis

Section: Chapter Questions

Problem 21P

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