1.What makes ionic bonds different from covalent bonds? Explain with respect to the bond formation between MgCl2 and N2. 2. A group of young researchers was working on a biochemical pathway. At that time, they produced an enzyme having altered active site. Do you think, the activity of the new enzyme would differ from the original one? Why? On a different reaction they found, an enzyme works best at a temperature near about 30 degree Celsius. At 60 degree Celsius, the enzyme becomes inactivated. Briefly explain, why that enzyme is not working at elevated temperature?

Chemistry How is lactase enzyme activity influenced by increasing ONPG concentration?

Which of the statements about enzymes are true? Generally, an enzyme is specific for a particular substrate. For example, thrombin catalyzes the hydrolysis of the peptide bond between Arg and Gly. An enzyme yields a specific product, whereas a nonbiological catalyst may produce more than one product with the occurance of side reactions. Catalysis occurs at the active site, which usually consists of a crevice on the surface of the enzyme. A substrate must bind to the active site before catalysis can occur. Nonbiological catalysts and enzymes tend to have a similar degree of reaction specificity.

help with questions 1 and 2 please

Enzymes do not require activation energy do not change requirment of activation energu increase requirment of activation energy lowest requirment of activation energy zymogen enzyme poison enzyme modulator enzyme precursor enzyme inhibitor

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4.     The amino acid Asp189 lies at the base of the substrate specificity pocket in the enzyme trypsin. a.   How is this related to typsin’s substrate specificity? Briefly describe the interactions between the substrate and the Asp 189. b.   If the Asp189 was replaced with a lysine residue, how would this affect substrate specificity? c.   The scientists that actually mutated the Asp189 to a lysine analyzed the three-dimensional structure of the enzyme and found that the lysine is actually not located in the specificity pocket. Instead, the Lys side chain reaches out of the base of the pocket, rendering the pocket nonpolar. With this additional information, determine how the substrate specificity would differ in the lysine-mutated enzyme.

When the reaction below reaches equilibrium, does the equilibrium lie on the left or the right side?  Briefly explain. ClO–  +  CH3CO2H  ⇌  HClO  +  CH3CO2–   When the terminal phosphate is cleaved from the adenosine triphosphate molecule, the products are adenosine diphosphate and inorganic phosphate,  ATP + H2O  ––>  ADP  +  Pi, where Pi stands for the various forms of phosphate that exist at the pH of the particular solution.  If the total concentration of Pi  is 2.5 x 10–2M, what are the concentrations of the predominant forms of phosphate that exist at pH 7.4?     Permanganate, MnO4–, can act as an oxidizing agent in both acidic and basic aqueous solutions. Balance each of the following reactions by the half–reaction method, showing all steps in the balancing process.   MnO4–   +   Al   ––>   MnO2   +   Al(OH)4–                                in aqueous base   MnO4–   +   CH3COOH   ––>   Mn+2   +   CO2                            in aqueous acid

9. Comment on the strategy of using an irreversible enzyme inhibitor or receptor antagonist. What is different from using a reversible inhibitor or antagonist? What does this mean for the drug structure? In what therapeutic areas is this a useful strategy?

2. What class of enzyme would expect to catalyze the following reaction? H,NCHCNHCHCO H,NCHCOH H,0 R R a. Oxidoreductase b. Transferase c. Hydrolase d. Lyase e. Isomerase