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 (A)oxygen affinity, (B)the Bohr effect, and (C)the Hillcoefficient? Explain your answers.

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 (A)oxygen affinity, (B)the Bohr effect, and (C)the Hillcoefficient? Explain your answers.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter11: The Blood

Section: Chapter Questions

Problem 1SQE

See similar textbooks

Similar questions

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
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 Hillcoefficient? Explain your answers.
) Dr Merrick is so excited to know the affinity constant Kd values for O2 binding to mammoth OBP and elephant hemoglobin at pH=7, that he starts speculating about the kinetics of binding to O2. If the ka value of mammoth EHb-O2 complex was the same as the ka value of mammoth OBP-O2 complex, what would be the ratio between the kd values of these complexes? Explain your reasoning. Hint: we are looking for the ratio kd(EHb)/kd(OBP) at pH=7.
In oxygenated hemoglobin, pKa 5 6.6 forthe histidines at position 146 on the -chain. In deoxygenated hemoglobin, the pKa of these residues is 8.2. How can this piece ofinformation be correlated with the Bohr effect?
How does the difference between the-chain and the -chain of hemoglobin explain the differences inoxygen binding between Hb A and Hb F?
What is the dominant biochemical activity or molecular interaction that Sickle Cell Anemia Hemoglobin Subunit beta-protein (P68871) is predicted to carry out?
2,3-Bisphosphoglycerate lies in a central cavity within the hemoglobin tetramer, stabilizing the T state. What would be the effect of mutations that placed the BPG-binding site on the surface of hemoglobin?
BPC is a heterotropic allosteric modulator. in which way does this compound change the uptake and release of oxygen in hemoglobin?
What is the role of 2, 3-Bisphosphoglycerate (2,3-BPG) in the function of haemoglobin as an oxygen carrier molecule? Explain the binding mechanism and effect of 2,3-BPG leading to the reduced oxygen binding affinity for haemoglobin and transitions in the T (deoxygenated) and R (oxygenated) states of haemoglobin.
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.
Apohemoglobin (apoHb) is a dimeric globular protein with two vacant heme‐binding. The preparationof apoHb is based on partial hemoglobin (Hb) unfolding to facilitate heme extraction into an organic solvent. What is an appropriate method for removing the heme? a. An acidic buffer to protonate the His axial ligand in the presence of ureaas the denaturing agent. b. An acidic buffer to protonate the His axial ligand in the presence of mercatoethanol as the denaturing agent. c. A basic buffer to deprotonate the His axial ligand in the presence of ureaas the denaturing agent. d. An basic buffer to protonate the His axial ligand in the presence of mercatoethanol as the denaturing agent.
In an experiment, hemoglobin is dissociated in a buffer and a subunit is isolated to study for its oxygen binding affinity. (i) What is the shape of the oxygen dissociation curve is expected in the experiment?Explain why. (ii) Is the Km of the isolated subunit higher or lower than the Km of an intact hemoglobin?