(b) Biotin is a coenzyme required for a key step in gluconeogenesis. (i) To which enzyme is biotin linked and what is the nature of the bond? (ii) What properties do the biotin and the linkage have that enable biotin to interact with two distinct active sites in this enzyme? (iii) What chemical steps take place at each of these active sites (no need to specify the complete reactions)?

Starting from glutamine ,glycine, aspartate, N-10 formal-ThF ,how many ATP equivalents are required for purine synthesis?

PLP is a cofactor for a number of enzymes involved in amino acid metabolism. Give an example of reaction in which PLP participates in cleavage of the a, b, and c bonds of an amino acid, as diagrammed in shown Fig.

What is the metabolic purpose of linking a fatty acid tocoenzyme A?

In the ATP-dependent formation of the peptide bond, it is found that Mg2+ ions or other positive charges are needed to stabilize a transition state. What chemical feature of the intermediate of this mechanism suggests the cause of this dependence?

What is the oligosaccharide-transferring moiety in N-link glycosylation?

You have discovered a new enzyme that has a nearly identical active site to chymotrypsin. This new enzyme uses the same catalytic triad and the same reaction mechanism as chymotrypsin. Your new enzyme differs from chymotrypsin because it cuts peptides at the C terminus of polar, non- ionizable R groups.A) Beginning with the first tetrahedral intermediate, draw the mechanism of catalysis that occurs to cleave the tripeptide Asn- Phe- Lys substrate ending your answer with the product and free enzyme.

The enzyme prenyl transferase is responsible for condensing isopentenyl pyrophosphate units during the second stage of cholesterol biogenesis. Which of the following intermediates could still form if prenyl transferase were inhibited? (A) farnesyl pyrophosphate(B) dimethylallyl pyrophosphate (C) squalene(D) geranyl pyrophosphate(E) lanosterol

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Describe how a) Mean Arterial Pressure, b) Maximal Oxygen Consumption, and c) Blood Flow are determined using its formula. In addition, you should explain what those factors are including cardiac output, stroke volume, heart rate, resistance, a-vO2 difference, etc. Describe how many ATPs can be generated by complete cycles of beta oxidation of free fatty acid with 20 carbons. You should indicate how many cycles of beta oxidation and Krebs cycle, and total number of products as well