Direct mutagenesis of Ca2+ ATPase gene resulted in the replacement of two amino acid residues - Asn111 and Asn114 to Ala. These substitutions led to the reduction in Ca2+ transport activity by 10% and 50%, respectively. On the other hand, directed mutagenesis that resulted in the alteration of four Glu residues in the lumenal loop of this transport protein to Ala, did not affect the Ca2+ transport. Provide the possible explanation for the observed differences in the Ca2+ transport activity between the protein with Asn->Ala substitution and the protein with Glu->Ala substitution.

Direct mutagenesis of Ca2+ ATPase gene resulted in the replacement of two amino acid residues - Asn111 and Asn114 to Ala. These substitutions led to the reduction in Ca2+ transport activity by 10% and 50%, respectively. On the other hand, directed mutagenesis that resulted in the alteration of four Glu residues in the lumenal loop of this transport protein to Ala, did not affect the Ca2+ transport. Provide the possible explanation for the observed differences in the Ca2+ transport activity between the protein with Asn->Ala substitution and the protein with Glu->Ala substitution.

Biology (MindTap Course List)

11th Edition

ISBN:9781337392938

Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg

Publisher:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg

Chapter14: Gene Regulation

Section: Chapter Questions

Problem 13TYU: INTERPRET DATA Develop a simple hypothesis that would explain the behavior of each of the following...

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