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bioRxiv · 10.1101/2020.06.23.166439

Spinal Column Architecture of the Flexible SPP1 Bacteriophage Tail Tube

Zinke, M.·Sachowsky, K.·Oester, C.·Zinn-Justin, S.·Ravelli, R. R.·Schroeder, G. F.·Habeck, M.·Lange, A.
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Abstract

Phage therapy has recently regained attention at combating multidrug-resistant bacteria. In 2019, tailed bacteriophages of the Siphoviridae family were engineered to successfully treat a disseminated bacterial infection after all other drugs had failed.(1) This family of phages features a long, flexible, non-contractile tail that has been difficult to characterize structurally. Here, we present the atomic structure of the tail-tube of the bacteriophage SPP1 - a member of this family. Our hybrid structure is based on the integration of structural restraints from solid-state NMR and a density map from cryo-EM. We show that the tail tube protein (TTP) gp17.1 organizes into hexameric rings that are stacked by flexible linker domains and, thus, form a hollow flexible tube with a negatively charged lumen suitable for the transport of DNA. One sentence summaryIntegrative structural biology by solid-state NMR and cryo-EM enables structure determination of the flexible tail of the bacteriophage SPP1.

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Zinke, M., Sachowsky, K., Oester, C., Zinn-Justin, S., Ravelli, R. R., Schroeder, G. F., Habeck, M., Lange, A.. 2020-06-23. Spinal Column Architecture of the Flexible SPP1 Bacteriophage Tail Tube. https://doi.org/10.1101/2020.06.23.166439

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