Question 7: Peptide nucleic acids (PNAS) exhibit greater stability as heteroduplexes with DNA (ie PNA-DNA duplex) than does double-stranded DNA (i.e. DNA-DNA duplex). However, peptide nucleic acids lack charged groups, making them largely insoluble under near-physiological conditions in aqueous buffer. Provide (1) an explanation for the increased stability of PNA-DNA duplexes (hint: consider intermolecular forces). (2) Additionally, propose modification(s) of the PNA scaffold DNA HO. that could increase solubility without drastically reducing duplex stability. PNA R1 HN Base Base Base Base =P-O° NH Base Base Но NH R2

Question 7: Peptide nucleic acids (PNAS) exhibit greater stability as heteroduplexes with DNA (ie PNA-DNA duplex) than does double-stranded DNA (i.e. DNA-DNA duplex). However, peptide nucleic acids lack charged groups, making them largely insoluble under near-physiological conditions in aqueous buffer. Provide (1) an explanation for the increased stability of PNA-DNA duplexes (hint: consider intermolecular forces). (2) Additionally, propose modification(s) of the PNA scaffold DNA HO. that could increase solubility without drastically reducing duplex stability. PNA R1 HN Base Base Base Base =P-O° NH Base Base Но NH R2

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

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