The enzyme phosphoglucomutase interconverts glucose-1-phosphate and glucose-6-phosphate. Why is this enzyme likely to include a side chain such as Ser in its active site?

A mutation has occurred that results in phosphofructokinase not being able to bind ATP in its allosteric site. What impact will this mutation have on the production of ATP in the cell?   Select one: a. If no ATP can bind to the allosteric site, then phosphofructokinase will not be able to add the phosphate to fructose-6-phosphate to make fructose-1,6-bisphosphate and glycolysis will not work. So no pyruvate, not cellular respiration.  b. If ATP cannot bind to the allosteric site, phosphofructokinase will not be activated to make more ATP by substrate-level phosphorylation. c. No impact on the production but will not be able to effectively shut off over production of ATP with feedback inhibition.

Thiamine is the vitamin precursor for a co-enzyme called thiamine pyrophosphate or TPP.    A patient diagnosed with thiamine deficiency exhibited fatigue and muscle cramps.  The muscle cramps have been related to the accumulation of specific metabolic acids.  On the following list, circle the metabolic acids that are most likely to accumulate in a thiamine deficiency?    Note:  There may be more than one.      Isocitrate Pyruvate Succinate α-ketoglutarate Malate Fumarate   (b) Provide a brief explanation for your answer to 1 (a) here

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 urea cycle can be summarized through the following reaction: O || H2N-C-OPO3 + COO- | H3N-CHCH₂COO b. O || H2N-C-NH2 1a Write the reactions, using structural formulas that lead to the formation of carbamoyl phosphate and its subsequent incorporation into the urea cycle. Name the enzymes and how they are activated. 1 + OOCCH=CHCOO- Write the rest of the reactions that constitute the urea cycle using structural formulas. Name the enzymes that catalyze each reaction. Indicate which reactions occur in the mitochondrion and which occur in the cytoplasm.

The following reaction would most likely be catalyzed by an enzyme of which class? sucrose + H2O → glucose + fructose

In the regulation of glycogen phosphorylase, which of the following statements is true? The inactive T form becomes activated when it gets dephosphorylated. The active R form is inhibited by glucose. Phosphoprotein phosphatase catalyzes the attachment of a phosphate group to a Ser residue in glycogen phosphorylase. The allosteric modulator glucose-6-phosphate promotes the conformation change from inactive T state to active R state.

Name which, if any, of the following are epimers ofd-glucose: d-mannose, d-galactose, d-ribose

For a lot of enzymes that work on fatty acids, the rate determining step is the release of the product from the active site. This means that the activation energy for product release is much higher than the free energy of catalysis. What enthalpic or entropic contributions would make the activation energy for product release so high and explain?