Download MendeleyBinding of a Pocket Factor to Hepatitis B Virus Capsids Changes the Rotamer Conformation of Phenylalanine 97.
Makbul, C., Kraft, C., Griessmann, M., Rasmussen, T., Katzenberger, K., Lappe, M., Pfarr, P., Stoffer, C., Stohr, M., Wandinger, A.M., Bottcher, B.(2021) Viruses 13
- PubMed: 34834922
- DOI: https://doi.org/10.3390/v13112115
- Primary Citation of Related Structures:
7PZ9, 7PZI, 7PZK, 7PZL, 7PZM, 7PZN - PubMed Abstract:
(1) Background: During maturation of the Hepatitis B virus, a viral polymerase inside the capsid transcribes a pre-genomic RNA into a partly double stranded DNA-genome. This is followed by envelopment with surface proteins inserted into a membrane. Envelopment is hypothetically regulated by a structural signal that reports the maturation state of the genome. NMR data suggest that such a signal can be mimicked by the binding of the detergent Triton X 100 to hydrophobic pockets in the capsid spikes. (2) Methods: We have used electron cryo-microscopy and image processing to elucidate the structural changes that are concomitant with the binding of Triton X 100. (3) Results: Our maps show that Triton X 100 binds with its hydrophobic head group inside the pocket. The hydrophilic tail delineates the outside of the spike and is coordinated via Lys-96. The binding of Triton X 100 changes the rotamer conformation of Phe-97 in helix 4, which enables a π-stacking interaction with Trp-62 in helix 3. Similar changes occur in mutants with low secretion phenotypes (P5T and L60V) and in a mutant with a pre-mature secretion phenotype (F97L). (4) Conclusion: Binding of Triton X 100 is unlikely to mimic structural maturation because mutants with different secretion phenotypes show similar structural responses.
Organizational Affiliation:
Rudolf Virchow Center, Center for Integrative and Translational Bioimaging, University of Würzburg, 97080 Würzburg, Germany.
