In active muscle cells, the pO₂ is about 10 torr at the cell surface and 1 torr at the mitochondria(the organelles where oxidative metabolism occurs). Calculate the percentage of bound oxygentransported to the mitochondria of muscle cells by myoglobin (KD = 2 torr).A new oxygen transport protein that exhibits cooperative binding has been isolated and is beingstudied in the lab. Calculate the Ko value if Y = 0.76 when pO₂2 = 18 torr (assume n = 2.5). Howdoes this compare to the K₂ value for hemoglobin? Does this protein bind more or less tightly tooxygen compared to hemoglobin?

Myoglobin and hemoglobin are oxygen storage and transport proteins. Myoglobin, whose primary…

Answered: In active muscle cells, the pO₂ is…

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter27: Metabolic Integration And Organ Specialization

Section: Chapter Questions

Problem 3P

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In active muscle cells, the pO2 is about 10 torr at the cell surface and 1 torr at the mitochondria(the organelles where oxidative metabolism occurs). Calculate the percentage of bound oxygentransported to the mitochondria of muscle cells by myoglobin (KD = 2 torr).
Heart and muscle cells, where myoglobin resides, maintains an intracellular pO2 of about 2.5 torr. Calculate the fractional saturation (for human myoglobin) if a small change (1 torr) in oxygen partial pressure occurs in either direction (ie what happens at 1.5 torr, what happens at 3.5 torr?) and explain how a small change in oxygen pressure dramatically changes the myoglobin oxygen binding.
Calculate the percent oxygen saturation of myoglobin if 7 of 15 binding sites are occupied..
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A new oxygen transport protein that exhibits cooperative binding has been isolated and is beingstudied in the lab. Calculate the KD value if Y = 0.76 when pO2 = 18 torr (assume n = 2.5). Howdoes this compare to the KD value for hemoglobin? Does this protein bind more or less tightly tooxygen compared to hemoglobin?
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1. a. In active muscle cells, the pO2 is about 10 torr at the cell surface and 1 torr at the mitochondria(the organelles where oxidative metabolism occurs). Calculate the percentage of bound oxygentransported to the mitochondria of muscle cells by myoglobin (KD = 2 torr). b. A new oxygen transport protein that exhibits cooperative binding has been isolated and is beingstudied in the lab. Calculate the KD value if Y = 0.76 when pO2 = 18 torr (assume n = 2.5). Howdoes this compare to the KD value for hemoglobin? Does this protein bind more or less tightly tooxygen compared to hemoglobin?
The drug troglitazone was used to treat diabetes but was withdrawn from the market when patientswho took the drug suffered from severe side effects. The data below show the activity of an enzymein the steroid biosynthetic pathway in the presence and absence of 10 µM troglitazone.[S] (µM) v0 (pmol min-1)Create a plot of 1/v0 vs. 1/[S]. Calculate KM and vmax in presence and absence of inhibitor. Whattype of inhibitor is troglitazone? Clearly support your answer.
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