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Due to the rising price of a barrel of crude oil, based on the Global Crude Oil Index (GCX), Speedway Stores must increase the price of a gallon of gasoline by 10% at all of its gas stations across the country. What category of risk does this represent for Speedway Stores? 

In Hemoglobin, explain why His E7 is essential (it is the one hanging on top of the heme) the importance of the quaternary structure in the binding with O2 there are 3 allosteric regulators (C02, H+ and BPG). List where they bind and which state (T or R) they stabilize.

Assume an interaction between the side chain of Glu  and the side chain of a neighboring Lysine residue. At which range of pH this interaction is favorable? Below you can see the tripeptide in his fully protonated form, the reference table and the structure of Lysine. Explain your answer.          

EXTRA POINTS: 10 Calculate the standard free-energy changes of the following metabolically important enzyme-catalyzed reaction at 25⁰C and pH 7.0 from the equilibrium constants given R = 8.314 J / mol·K and T= 25°C = 298K.   

Since enzymes are not rigid molecules but rather flexible proteins, which of the following may be attributed to this fact?   a.  active sites are able to conform to the shape of the substrate   b.  catalytic residues are oriented in such as way to aid in bond breakage and bond formation   c.  strain is placed upon the substrate while it binds to the enzyme   d.  near-attack conformations are achieved during formation of the transition state during an enzyme catalyzed reaction   e.  all of the above are correct

Which statement is correct about the Michaelis-Menten constant, Km, for the kinetic mechanism below?   a.  It is numerically equal to the substrate concentration required to achieve one half the maximum velocity.   b.  Its defined as Km = k1/(k−1 + k2).   c.  It is approximately equal to the dissociation constant for the enzyme-substrate complex to E + P.   d.  The value of Km is constant for an enzyme regardless of the specific substrate molecule used to determine it.   e.  Its numeric value has the units of moles−1.

15. The catalytic mechanism below is an example of:   a.  covalent nucleophilic catalysis.   b.  covalent electrophilic catalysis.   c.  specific base catalysis.   d.  general base catalysis.   e.  low barrier hydrogen bond catalysis.  

In transforming the Michaelis-Menten equation into a straight line equation, y = mx + b, the Lineweaver-Burk double reciprocal plot, which of the following is NOT a true representation?   a.  slope = Km/Vmax   b.  y-intercept is 1/Vmax   c.  x-intercept is 1/Km   d.  y = 1/V   e.  x = 1/[S]

All are characteristic of allosteric enzymes EXCEPT:   a.  Effectors may show stimulatory or inhibitory activity.   b.  They have multiple subunits.   c.  They obey Michaelis-Menten kinetics.   d.  The regulatory effect is by altering conformation and interaction of subunits.   e.  Binding one subunit impacts binding of substrate to other subunits.  

All of the following are correct statements about enzyme regulation EXCEPT:   a.  Enzymes can be inhibited by the products they produce.   b.  Enzymes can be inactivated by the addition of a functional group.   c.  Coenzyme and substrate availability can regulate enzyme reaction rate.   d.  The reaction rate slows as equilibrium is approached.   e.  The activity of an enzyme is covalently affected by allosteric regulators.