03 Hemoglobin
- component of RBC, carries O2
- blue and red: globin chains--- date: 2021-03-20
03 Hemoglobin
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related:
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green: heme, 4 in a hemoglobin
Globin
- sickle cell: abnormal hemoglobin
Heme
- porphyria: defects in enzymes making the porphyrin
- RBC with BPG Mutase makes 2, 3 BPG
- bad for red cells: sacrifices ATP (pyruvate normally used to make ATP)
Hemoglobin Binding
- favored in tissues to release O2. T for tissues
- relaxed form favored in lungs to pick up more O2
- myoglobin: bind each O2 molecule equally, linear increase until plateau
- hemoglobin: S shaped curve. Hard to bind first one and then speeds up
- example of allosteric effect
Allosteric Effects
CO
- loses cooperativity
MetHB
- rest of Fe2 binds O2 with higher affinity, left shift curve
- methylene blue reduces Fe3 to Fe2
- vitamin C reduces Fe3 to 2
- SOB from methemoblobinemia
- interferes with pulse ox
- normal amount of O2 in blood
CN
- functional hypoxia: enough O2 around but can't use them
- inhibits cytochrome oxidase a3
