You have discovered a novel protein that has a pl = 5.5. To study the functional properties of this new protein your research group has made a mutant that contains two amino acid changes-namely, a surface Phe residue in the normal protein has been replace by His (side chain pk, = 6.1), and a surface Gln has been replace by Glu (side chain pk = 6.0). The pl of the %3D mutant protein is predicted to be: A. Greater than the pl of the normal protein.

You have discovered a novel protein that has a pl = 5.5. To study the functional properties of this new protein your research group has made a mutant that contains two amino acid changes-namely, a surface Phe residue in the normal protein has been replace by His (side chain pk, = 6.1), and a surface Gln has been replace by Glu (side chain pk = 6.0). The pl of the %3D mutant protein is predicted to be: A. Greater than the pl of the normal protein.

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

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A particular protein has the amino acid sequenceN . . . Ala-Pro-His-Trp-Arg-Lys-Gly-Val-Thr . . . Cwithin its primary structure. A geneticist studyingmutations affecting this protein discovered that several of the mutants produced shortened protein molecules that terminated within this region. In one ofthem, the His became the terminal amino acid.a. What DNA single-base change(s) would cause theprotein to terminate at the His residue?b. What other potential sites do you see in the DNAsequence encoding this protein where mutation ofa single base pair would cause premature termination of translation?
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