Hb Structure/Function

Question 1

• Hb Structure?
• Allostery?
• Positive cooperativity?
• T state?
• Relaxed state?
• 100 mgHg; 60 mmHg; 40mmHh; 30mmHg; 10mmHg
• Shifts curve right (4)?
• Alpha chrom? Beta? Embryonic Hb’s? Fetal? Adult?

Answer 1

• A2B2 tetramer with 4 heme groups (protophorin + iron)
• Bind 1 O2 causes conf. change that changes affinity at other sites
• When 1 O2 binds; increased affinity
• Deoxy
• Oxy
• 98%; 90%; 75%; 30%; 10%
• Low Ph, Incr. CO2; Incr. temp; Incr. 2,3 BPG (prod of glycolysis; stabilizes T config
• 16; 11; Gower 1 (Z2E2), Gower 2 (A2E2), Portland (Z2Y2); HbF; HbA, HbA2

Question 2

• Fetal Hb: Increased affinity why? Stabilized? Shifts curve?
• High affinity Hb variant? Shift?
• Low affinity variant shift? Rare?
• Unstable Hb variants? (2)
• Methemoglobin? Who is more suseptible? Diagnosed how? Treatment?
• CO poisioning: Symptoms? Treatment?
• Pulse ox uses what law? not good with? only works with?

Answer 2

• Binds 2,3BPG poorly; stab. R state, Left
• Hb Chesapeake; Left
• Right; Rare
• Zurich, Kolm
• Fe3+ (ferric) not reduced to Fe2+ (ferrous) by NADPH; Newborns with HbF; cyanotic with normal BP, chocalate blood; meth blue for cosmetic
• Cherry red with no cyanosis; 100% O2
• Beer-Lambert; Methemo; pulse flow