The following observations are made on an unknownmembrane protein, X. It can be extracted from disrupted erythrocyte membranes into aconcentrated salt solution, and it can be cleaved into fragments by proteolytic enzymes. Treatment of erythrocytes with proteolytic enzymes followed by disruption and extraction of membrane components yields intact X. However, treatment of erythrocyte “ghosts” (which consist of just plasma membranes, produced by disrupting the cells and washing outthe hemoglobin) with proteolytic enzymes, followed by disruption and extraction, yields extensively fragmented X. What do these observations indicate about the location of X in the plasma membrane? Do the properties of X resemble those of an integral or peripheral membrane protein?

The following observations are made on an unknownmembrane protein, X. It can be extracted from disrupted erythrocyte membranes into aconcentrated salt solution, and it can be cleaved into fragments by proteolytic enzymes. Treatment of erythrocytes with proteolytic enzymes followed by disruption and extraction of membrane components yields intact X. However, treatment of erythrocyte “ghosts” (which consist of just plasma membranes, produced by disrupting the cells and washing outthe hemoglobin) with proteolytic enzymes, followed by disruption and extraction, yields extensively fragmented X. What do these observations indicate about the location of X in the plasma membrane? Do the properties of X resemble those of an integral or peripheral membrane protein?

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter9: Cell Communication

Section: Chapter Questions

Problem 1ITD

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