Lone-pair–pi interactions: analysis of the physical origin and biolological implications

NOVOTNÝ, Jan, Sophia BAZZI, Radek MAREK and Jiří KOZELKA. Lone-pair–pi interactions: analysis of the physical origin and biolological implications. Physical Chemistry Chemical Physics. Royal Society of Chemistry, vol. 18, No 28, p. 19472-19481. ISSN 1463-9076. doi:10.1039/C6CP01524G. 2016.

Basic information

• Original name: Lone-pair–pi interactions: analysis of the physical origin and biolological implications
• Authors: NOVOTNÝ, Jan (203 Czech Republic, belonging to the institution), Sophia BAZZI (364 Islamic Republic of Iran, belonging to the institution), Radek MAREK (203 Czech Republic, belonging to the institution) and Jiří KOZELKA (250 France, guarantor, belonging to the institution).
• Edition: Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2016, 1463-9076.

Other information

• Original language: English
• Type of outcome: Article in a journal
• Field of Study: 10403 Physical chemistry
• Country of publisher: United Kingdom of Great Britain and Northern Ireland
• Confidentiality degree: is not subject to a state or trade secret
• WWW: DOI: 10.1039/C6CP01524G
• Impact factor: Impact factor: 4.123
• RIV identification code: RIV/00216224:14310/16:00087988
• Organization unit: Faculty of Science
• Doi: http://dx.doi.org/10.1039/C6CP01524G
• UT WoS: 000379939100089
• Keywords in English: lone-pair-pi interaction; anion-pi; DFT; energy decomposition analysis
• Tags: AKR, rivok
• Tags: International impact, Reviewed

Abstract

Lone-pair-pi (lp-pi) interactions have been suggested to stabilize DNA and protein structures, and to participate in the formation of DNA-protein complexes. To elucidate their physical origin, we have carried out a theoretical multi-approach analysis of two biologically relevant model systems, the water-indole and water-uracil complexes, which we compared with the structurally similar chloride-tetracyanobenzene (TCB) complex previously shown to contain a strong charge-transfer (CT) binding component. We demonstrate that the CT component in lp-pi interactions between water and indole/uracil is significantly smaller than that stabilizing the Cl-TCB reference system. The strong lp(Cl-)-pi(TCB)* orbital interaction is characterized by a small energy gap and an efficient lp-pi* overlap. In contrast, in lp-pi interactions between water and indole or uracil, the corresponding energy gap is larger and the overlap less efficient. As a result, water-uracil and water-indole interactions are weak forces composed by smaller contributions from electrostatics, polarization, dispersion, and charge transfer. In addition, indole exhibits a negative electrostatic potential at its pi-face, making lp-pi interactions less favorable than O-H···pi hydrogen bonding. Consequently, some of the water-tryptophan contacts observed in X-ray structures of proteins and previously interpreted as lp-pi interactions [Luisi et al., Proteins 2004, 57, 1-8], might in fact arise from O-H···pi hydrogen bonding.

Links

• GA14-14654S, research and development project: Name: Studium fyzikální podstaty interakcí lone-pair-pi v biomolekulárních systémech. Role interakcí lone-pair-pi při stabilizaci proteinu Engrailed (Acronym: Lone-pair-pi interactions)

Investor: Czech Science Foundation

• LQ1601, research and development project: Name: CEITEC 2020 (Acronym: CEITEC2020)

Investor: Ministry of Education, Youth and Sports of the CR