A) llustrate in molecular detail how hemoglobin's reduced oxygen affinity is caused by protonation of the histidine side chain. b) what is the pKa of the histidine side-chain ionizable group expected to have?

In a molecular disease of hemoglobin, Hemoglobin Rainier, Tyr 145β is replaced by Cys, which forms a disulfide bond with another Cysresidue in the same subunit. This prevents the formation of ion pairs that normally stabilize the T state. How does hemoglobin Rainier differ from normal hemoglobin with respect to the Hill coefficient

The 2-3 phosphoglycerate (BFG) binds to the central gap formed by the hemoglobin monomers (a2b2) facilitating the reversible release of oxygen. Approximate relationships between BFG concentrations in red blood cells and Pos in hemoglobin are in the table.a) Draw the reaction schemeb) Write the forces that condition the union between hemoglobin and BFG

Please fill in the following blanks with the options that correctly finishes the sentence. a. At a low O₂ pressure the [Select] hemoglobin is in a [Select] [Select] [Select] 9 [Select] " bond with [Select] heme, and the protein's central channel is [Select] b. The proximal histidine forms a(n) [Select] state is stabilized. In this conformation state, the heme prosthetic groups is each subunit's heme is more likely to be the proximal histidine is [Select ] bond with while the distal histidine forms a(n) [Select] to the

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)

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.

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.

List 4 different actiated carrier molecules, for each one, list both the oxided and reduced forms

Consider a short peptide with the sequence M-C-Q-L-Y-P-E-D-K. List the ionizable groups in this peptide, and the net charge of the whole peptide at pH a) 1.5, b) 7.0, and c)12.0.

Proline is one of the amino acids in the "special" groups of sidechains. One reason for this is the dramatic impact it can have on secondary structure.  a) draw the lewis structure for a tripeptide with the sequence Ala-Pro-Ala b) Proline residues are rarely found in alpha helices - in fact, they are often referred to as helix-disrupting amino acids. Thinking about intermolecular interactions, provide an explanation for why proline might disrupt alpha-helices. c) Proline also has a similar effect on beta-sheets, and is rarely found in the middle of beta sheets. Thinking about noncovalent interactions, provide an explanation for why proline might disrupt beta-sheets.