Figure 6-33 (Subunit interactions in an allosteric enzyme, and interactions with inhibitors and activators) depicts allosteric modulation of an enzyme through non-covalent interactions. What features of an activator might lead to different levels of enzyme regulation? Select one or more: a. ability to cause a conformational change that results in an altered activity. b. affinity for the regulatory site c. boiling point d. bond flexibility (i.e. abundance of freely rotating single bonds instead of more rigid bonds like double bonds) e. molecular weight

Some enzymes can be regulated by covalent modification, in which a group is covalently bonded to an amino acid side chain. Phosphorylation of side chains is a common regulatory covalent modification. In this essay, you will explore phosphorylation of side chains.  Compare and contrast the types of interactions a free alcohol side chain such as serine could make with that of a phosphorylated alcohol such as phosphoserine (pSer). Could this modification affect the 3D structure of the protein? How?  Imagine you are trying to separate a protein containing an unphosphorylated S residue from the same protein containing a pSer residue. Discuss how you could use ion-exchange chromatography to separate these two proteins

The natural enzyme is recreated by mixing isolated regulatory and catalytic subunits of ATCase. What biological relevance does this observation have?

A potent inhibitor effectively inhibits an enzyme catalyzed reaction. What kind of a Ki value you would expect for a potent inhibitor?

In bacteria, isocitrate dehydrogenase is regulated by phosphorylation of a specific Ser residue in the enzyme active site. X-ray structures of the phosphorylated and the nonphosphorylated enzyme show no significant conformational differences. How does phosphorylation 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.

this is not a writing assignment or essay  just give a brief explanation

Although we have introduced catalytic strategies separately, an enzyme typically employs more than one during a reaction. The catalytic strategies employed by serine protease include: Select one or more: O a. reduction of ASt b. transition state stabilization Oc. metal-assisted catalysis O d. acid/base catalysis O e. covalent catalysis