Journal of Molecular Modeling

, 17:2169 | Cite as

Do the substituent effects affect conformational freedom of squalene in hopene biosynthesis?

  • Marcin NowosielskiEmail author
  • Marcin Hoffmann
Original Paper


The analysis of biochemical processes is one of the main challenges for modern computational chemistry. Probably the biggest issue facing scientists in this case is the number of factors that have to be taken into account, as even those factors that do not seem to be meaningful may eventually be crucial. Such a belief led to the investigation on the substituent effects during squalene cyclization process. We focused on the formation of lanosterol ring A through squalene epoxide and an analogue process observed in bacteria, leading to the hopene formation without an intermediate oxide. Interestingly, our results indicate that, opposite of chemical intuition, a more substituted chain is more likely to adopt a conformation suitable for the cyclization process. Presumably the rational for this behavior is the presence of intermolecular CH⋅⋅⋅π interactions between the hydrogen atoms from methyl groups and the squalene π bonds in the open-chain structure. The effect seems to have a firm impact on the hopene formation process. Calculations were performed using two different methods: MP2 and M06-2X, combined with the cc-pVDZ basis set.


Conformational freedom Hopene Lanosterol Squalene Substituent effects 



MH thanks the Foundation for Polish Science for support via FOCUS program. MN thanks for the support via InterMolMed project (contract number POIG.01.01.02-10-107/09). Calculations were made possible thanks to the PL-Grid project, contract number: POIG.02.03.00-00-007/08-00, website: The project is co-funded by the European Regional Development Fund as part of the Innovative Economy Program.

Supplementary material

894_2011_1103_MOESM1_ESM.pdf (399 kb)
Esm 1 (PDF 399 kb)


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.BioInfoBank InstitutePoznańPoland
  2. 2.Institute for Medical BiologyPolish Academy of SciencesLodzPoland
  3. 3.Quantum Chemistry Group, Department of ChemistryAdam Mickiewicz UniversityPoznanPoland

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