Unconfirmed rumour has it that the NASA Curiosity rover may have found evidence for the existence of life on the Mars surface in the form of traces of molecules that seem to resemble an amino acid. While the scientific soundness of these claims remains fiercely debated amongst researchers the initial analysis of the alien amino acid suggested that it carried three different ionisable groups. This included an alpha carboxyl group with a pka of 2.30 but surprisingly no alpha amino group. In addition the amino acid contained both the side chains found in glutamate pka 4.25 and the one found in lysine pka 10.79. i) In less than 50 words provide a general explanation on how you can determine the pI of the alien amino acid. ii) Use the pka values to determine the isoelectric point of the alien amino acid to two decimal places, show your working out and state the final result in a full sentence.

Unconfirmed rumour has it that the NASA Curiosity rover may have found evidence for the existence of life on the Mars surface in the form of traces of molecules that seem to resemble an amino acid. While the scientific soundness of these claims remains fiercely debated amongst researchers the initial analysis of the alien amino acid suggested that it carried three different ionisable groups. This included an alpha carboxyl group with a pka of 2.30 but surprisingly no alpha amino group. In addition the amino acid contained both the side chains found in glutamate pka 4.25 and the one found in lysine pka 10.79. i) In less than 50 words provide a general explanation on how you can determine the pI of the alien amino acid. ii) Use the pka values to determine the isoelectric point of the alien amino acid to two decimal places, show your working out and state the final result in a full sentence.

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter10: From Proteins To Phenotypes

Section: Chapter Questions

Problem 14QP: If phenylalanine was not an essential amino acid, would diet therapy (the elimination of...

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