On the Importance of Intermediate Internal Charge Repulsion for the Synthesis of Multifunctional Pores

Article Article scientifique Article On the Importance of Intermediate Internal Charge Repulsion for the Synthesis of Multifunctional Pores eng 2002 author Baumeister Bodo 514413 author Som Abhigyan 524743 author Das Gopal 518425 author Sakai Naomi 0000-0002-9460-1944 131140 author Vilbois Francis author Gerard David 27973 author Shahi Shatrughan Prasad 522692 author Matile Stefan 0000-0002-8537-8349 129654 2740-2753 10.1002/1522-2675(200209)85:9<2740::AID-HLCA2740>3.0.CO;2-C 0018-019X Intermediate internal charge repulsion (ICR) is required to create synthetic pores with large, stable, transmembrane, and variably functionalized space. This conclusion is drawn from maximal transport and, in one case, catalytic activity of p-octiphenyl ß-barrel pores with internal lysine, aspartate, and histidine residues around pH 7, 6, and 4.5, respectively. pKa Simulations corroborate the experimental correlation of intermediate ICR with activity and suggest that insufficient ICR causes pore implosion' and excess ICR pore explosion'. Esterolysis experiments support the view that the formation of stable space within multifunctional p-octiphenyl ß-barrels requires more ICR in bilayer membranes than in H2O. Multivalency effects are thought to account for p-octiphenyl ß-barrel expansion with increasing number of ß-sheets, and proximity effects for unchanged pH profiles with increasing ß-sheet length. Q-TOF-nano-ESI-MS barrel-denaturation experiments indicate that contributions from internal counterion effects are not negligible. The overall characteristics of p-octiphenyl ß-barrel pores with internal lysine, aspartate, and histidine residues, unlike de novo a-barrels' and similarly to certain biological channels, underscore the usefulness of rigid-rod molecules to preorganize complex multifunctional supramolecular architecture. Dewey 540 36 Département de chimie organique 141 false Helvetica chimica acta 85 9 46225b95-47a2-4010-b4aa-5fa68dc54a16 Article Restricted file1.pdf 323097 application/pdf restrictedAccess Faculté des sciences / Section de chimie et biochimie / Département de chimie organique

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On the Importance of Intermediate Internal Charge Repulsion for the Synthesis of Multifunctional Pores	Helvetica chimica acta			2002	552	0

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Shahi, Shatrughan Prasad