A variant of hemoglobin (Boston variant; mutation His E7(58)α → Tyr) promotes methemoglobin formation involving the α (alpha) subunits. What is the maximum value of the Hill constant (n) that you could measure for the Boston variant of hemoglobin?   log (YO2 / 1 - YO2 ) = log pO2 - logP50 Please break down each step of the Hill equation and explain why the result for n is valid from a logical standpoint.

A one-to-one protein (P)-ligand (L) complexation (P + L PL) has a dissociation equilibrium constant (Kd) value of 100 nM at 25°C, and the Kd remains the same at 37°C. 1) What is AS of binding at 25°C? Assume ACp of the binding is 0 over the temperature range. AS = 1.34E2 kJ/(mol*K) (note the unit!!) (sig. fig =3) 2) What is the concentration of the PL complex formed at equilibrium when you mix 0.20 uM (microM) of Protein and 1.0 uM of Ligand together at 37°C? PL at equilibrium = 8.1E-1 uM (note the unit!!) (sig. fig =2)

HbA1c is a glycated hemoglobin in which a glucose molecule is covalently bound to the N-terminal valine of a hemoglobin subunit.  True  False

In one type of hemoglobin variant, lysine EF6 is replaced by an aspartic acid residue. What would be the effects of this mutation on the affinity of the hemoglobin for 2,3 BPG and oxygen? The affinity for 2,3-BPG would increase, and for oxygen would decrease. The affinity for 2,3-BPG would decrease, and for oxygen would decrease. The affinities for 2,3-BPG and for oxygen would be unaffected. The affinity for 2,3-BPG would increase, and for oxygen would increase. The affinity for 2,3-BPG would decrease, and for oxygen would increase.

The ABO blood group antigens are the terminal sugars covalently linked to the end of the glycolipid in the red blood cellmembrane. The H antigen is the precursor of the A and Bantigens. Individuals with type A blood produce a gene thatcodes for an enzyme that adds N-acetylgalactosamine in ana(1,3) linkage to the Gal* residue in the H antigen. Type Bblood requires that an enzyme add a d-a galactose in an a(1,3) linkage to the Gal*. Draw the structures of the A andB antigens.

You have discovered a new hemoglobin variant you are calling Hb-21. You have noticed the following from your studies of Hb-21: - The binding constant of Hb-21 is the same at pH 7.1 and 7.4.- The binding constant curves generated by Hb-21 and O2 are sigmoidal.- The Hill coefficient for Hb-21 is 3.-The binding constant for Hb-21 with O2 in the presence of 5mM 2,3-bisphosphglycerate is about 6-times lower instead of the 8-times lower that is observed under these conditions for the wild type enzyme. Use this information to answer questions: Based on this information which of these features of hemoglobin would you conclude are altered in Hb-21 as compared to the wild type hemoglobin? ____ the cooperativity.____ the amount of T versus R state in the tissues. ____ the Bohr effect. What is the major issue for an individual with the Hb-21 variant? Explain exactly what aspect of hemoglobin’s function is altered.

The folding and unfolding rate constants for a myoglobin mutant have been determined. The unfolding rate constant ke-u = 3.62 x 10-55 and the folding rate constant ku-p = 255 s1, where Fis the folded protein and U is the unfolded (denatured) protein. For wild-type myoglobin, AG;u = +37.4 kJ/mol. Which myoglobin is more thermodynamically stable, the mutant or the wild-type?

Normal Hgb is referred to as HbA and contains 4 subunits, 2 a-globin chains and 2 B-globin chains, arranged as two dimers of aß. In Sickle Cell Disease, both B-globin chains are altered in the dimers (aßS/aßS). Q3: Which level of structure does the aß/aß and aßS/aßS in HbA and HbS describe?

The mutation in hemoglobin at B82 Lys → Asp results in lowered O,-binding affinity compared to normal hemoglobin. B82 is one of the residues that lines the 2,3-BPG binding site (see Figure 7.29; B82 is adjacent to His143). Based on the location of this residue and the differences between Lys and Asp, sug- gest a rationale for the observed reduction in Oz-binding affinity.

Give typed explanation  Which of the following effects is NOT true? If stripped Hb is treated with 2,3-BPG, the O2-binding curve for Hb will shift left. If stripped Hb is treated with 2,3-BPG and CO2, the O2-binding curve for Hb will mirror that of fully intact Hb. If stripped Hb is treated with CO2, the O2-binding curve for Hb will shift right. All of the listed effects are true.