@article{AndresGohlkeBroekeretal.2013,
  author    = {Andres, Dorothee and Gohlke, Ulrich and Br{\"o}ker, Nina Kristin and Schulze, Stefan and Rabsch, Wolfgang and Heinemann, Udo and Barbirz, Stefanie and Seckler, Robert},
  title     = {An essential serotype recognition pocket on phage P22 tailspike protein forces Salmonella enterica serovar Paratyphi A O-antigen fragments to bind as nonsolution conformers},
  series = {Glycobiology},
  volume    = {23},
  journal   = {Glycobiology},
  number    = {4},
  publisher = {Oxford Univ. Press},
  address   = {Cary},
  issn      = {0959-6658},
  doi       = {10.1093/glycob/cws224},
  pages     = {486 -- 494},
  year      = {2013},
  abstract  = {Bacteriophage P22 recognizes O-antigen polysaccharides of Salmonella enterica subsp. enterica (S.) with its tailspike protein (TSP). In the serovars S. Typhimurium, S. Enteritidis, and S. Paratyphi A, the tetrasaccharide repeat units of the respective O-antigens consist of an identical main chain trisaccharide but different 3,6-dideoxyhexose substituents. Here, the epimers abequose, tyvelose and paratose determine the specific serotype. P22 TSP recognizes O-antigen octasaccharides in an extended binding site with a single 3,6-dideoxyhexose binding pocket. We have isolated S. Paratyphi A octasaccharides which were not available previously and determined the crystal structure of their complex with P22 TSP. We discuss our data together with crystal structures of complexes with S. Typhimurium and S. Enteritidis octasaccharides determined earlier. Isothermal titration calorimetry showed that S. Paratyphi A octasaccharide binds P22 TSP less tightly, with a difference in binding free energy of similar to 7 kJ mol(-1) at 20 degrees C compared with S. Typhimurium and S. Enteritidis octasaccharides. Individual protein-carbohydrate contacts were probed by amino acid replacements showing that the dideoxyhexose pocket contributes to binding of all three serotypes. However, S. Paratyphi A octasaccharides bind in a conformation with an energetically unfavorable phi/epsilon glycosidic bond angle combination. In contrast, octasaccharides from the other serotypes bind as solution-like conformers. Two water molecules are conserved in all P22 TSP complexes with octasaccharides of different serotypes. They line the dideoxyhexose binding pocket and force the S. Paratyphi A octasaccharides to bind as nonsolution conformers. This emphasizes the role of solvent as part of carbohydrate binding sites.},
  language  = {en}
}
@article{AndresRoskeDoeringetal.2012,
  author    = {Andres, Dorothee and Roske, Yvette and Doering, Carolin and Heinemann, Udo and Seckler, Robert and Barbirz, Stefanie},
  title     = {Tail morphology controls DNA release in two Salmonella phages with one lipopolysaccharide receptor recognition system},
  series = {Molecular microbiology},
  volume    = {83},
  journal   = {Molecular microbiology},
  number    = {6},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0950-382X},
  doi       = {10.1111/j.1365-2958.2012.08006.x},
  pages     = {1244 -- 1253},
  year      = {2012},
  abstract  = {Bacteriophages use specific tail proteins to recognize host cells. It is still not understood to molecular detail how the signal is transmitted over the tail to initiate infection. We have analysed in vitro DNA ejection in long-tailed siphovirus 9NA and short-tailed podovirus P22 upon incubation with Salmonella typhimurium lipopolysaccharide (LPS). We showed for the first time that LPS alone was sufficient to elicit DNA release from a siphovirus in vitro. Crystal structure analysis revealed that both phages use similar tailspike proteins for LPS recognition. Tailspike proteins hydrolyse LPS O antigen to position the phage on the cell surface. Thus we were able to compare in vitro DNA ejection processes from two phages with different morphologies with the same receptor under identical experimental conditions. Siphovirus 9NA ejected its DNA about 30 times faster than podovirus P22. DNA ejection is under control of the conformational opening of the particle and has a similar activation barrier in 9NA and P22. Our data suggest that tail morphology influences the efficiencies of particle opening given an identical initial receptor interaction event.},
  language  = {en}
}
@article{SeulMuellerAndresetal.2014,
  author    = {Seul, Anait and M{\"u}ller, J{\"u}rgen J. and Andres, Dorothee and Stettner, Eva and Heinemann, Udo and Seckler, Robert},
  title     = {Bacteriophage P22 tailspike: structure of the complete protein and function of the interdomain linker},
  series = {Acta crystallographica : Section D, Biological crystallography},
  volume    = {70},
  journal   = {Acta crystallographica : Section D, Biological crystallography},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1399-0047},
  doi       = {10.1107/S1399004714002685},
  pages     = {1336 -- 1345},
  year      = {2014},
  abstract  = {Attachment of phages to host cells, followed by phage DNA ejection, represents the first stage of viral infection of bacteria. Salmonella phage P22 has been extensively studied, serving as an experimental model for bacterial infection by phages. P22 engages bacteria by binding to the sugar moiety of lipopolysaccharides using the viral tailspike protein for attachment. While the structures of the N-terminal particle-binding domain and the major receptor-binding domain of the tailspike have been analyzed individually, the three-dimensional organization of the intact protein, including the highly conserved linker region between the two domains, remained unknown. A single amino-acid exchange in the linker sequence made it possible to crystallize the full-length protein. Two crystal structures of the linker region are presented: one attached to the N-terminal domain and the other present within the complete tailspike protein. Both retain their biological function, but the mutated full-length tailspike displays a retarded folding pathway. Fitting of the full-length tailspike into a published cryo-electron microscopy map of the P22 virion requires an elastic distortion of the crystal structure. The conservation of the linker suggests a role in signal transmission from the distal tip of the molecule to the phage head, eventually leading to DNA ejection.},
  language  = {en}
}
@article{BroekerRoskeVallerianietal.2019,
  author    = {Broeker, Nina K. and Roske, Yvette and Valleriani, Angelo and Stephan, Mareike Sophia and Andres, Dorothee and Koetz, Joachim and Heinemann, Udo and Barbirz, Stefanie},
  title     = {Time-resolved DNA release from an O-antigen-specific Salmonella bacteriophage with a contractile tail},
  series = {The journal of biological chemistry},
  volume    = {294},
  journal   = {The journal of biological chemistry},
  number    = {31},
  publisher = {American Society for Biochemistry and Molecular Biology},
  address   = {Bethesda},
  issn      = {1083-351X},
  doi       = {10.1074/jbc.RA119.008133},
  pages     = {11751 -- 11761},
  year      = {2019},
  abstract  = {Myoviruses, bacteriophages with T4-like architecture, must contract their tails prior to DNA release. However, quantitative kinetic data on myovirus particle opening are lacking, although they are promising tools in bacteriophage-based antimicrobial strategies directed against Gram-negative hosts. For the first time, we show time-resolved DNA ejection from a bacteriophage with a contractile tail, the multi-O-antigen-specific Salmonella myovirus Det7. DNA release from Det7 was triggered by lipopolysaccharide (LPS) O-antigen receptors and notably slower than in noncontractile-tailed siphoviruses. Det7 showed two individual kinetic steps for tail contraction and particle opening. Our in vitro studies showed that highly specialized tailspike proteins (TSPs) are necessary to attach the particle to LPS. A P22-like TSP confers specificity for the Salmonella Typhimurium O-antigen. Moreover, crystal structure analysis at 1.63 angstrom resolution confirmed that Det7 recognized the Salmonella Anatum O-antigen via an E15-like TSP, DettilonTSP. DNA ejection triggered by LPS from either host showed similar velocities, so particle opening is thus a process independent of O-antigen composition and the recognizing TSP. In Det7, at permissive temperatures TSPs mediate O-antigen cleavage and couple cell surface binding with DNA ejection, but no irreversible adsorption occurred at low temperatures. This finding was in contrast to short-tailed Salmonella podoviruses, illustrating that tailed phages use common particle-opening mechanisms but have specialized into different infection niches.},
  language  = {en}
}