Seiko Yamada

Publications (3)8.59 Total impact

• Article: The host-binding domain of the P2 phage tail spike reveals a trimeric iron-binding structure.

  Eiki Yamashita, Atsushi Nakagawa, Junichi Takahashi, Kin-ichi Tsunoda, Seiko Yamada, Shigeki Takeda
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  ABSTRACT: The adsorption and infection of bacteriophage P2 is mediated by tail fibres and tail spikes. The tail spikes on the tail baseplate are used to irreversibly adsorb to the host cells. Recently, a P2 phage tail-spike protein, gpV, was purified and it was shown that a C-terminal domain, Ser87-Leu211, is sufficient for the binding of gpV to host Escherichia coli membranes [Kageyama et al. (2009), Biochemistry, 48, 10129-10135]. In this paper, the crystal structure of the C-terminal domain of P2 gpV is reported. The structure is a triangular pyramid and looks like a spearhead composed of an intertwined β-sheet, a triple β-helix and a metal-binding region containing iron, calcium and chloride ions.
  Acta Crystallographica Section F Structural Biology and Crystallization Communications 08/2011; 67(Pt 8):837-41. · 0.51 Impact Factor
• Article: The C-terminal domain is sufficient for host-binding activity of the Mu phage tail-spike protein.

  Hidetaka Suzuki, Seiko Yamada, Yoshiharu Toyama, Shigeki Takeda
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  ABSTRACT: The Mu phage virion contains tail-spike proteins beneath the baseplate, which it uses to adsorb to the outer membrane of Escherichia coli during the infection process. The tail spikes are composed of gene product 45 (gp45), which contains 197 amino acid residues. In this study, we purified and characterized both the full-length and the C-terminal domains of recombinant gp45 to identify the functional and structural domains. Limited proteolysis resulted in a Ser64-Gln197 sequence, which was composed of a stable C-terminal domain. Analytical ultracentrifugation of the recombinant C-terminal domain (gp45-C) indicated that the molecular weight of gp45-C was about 58 kDa and formed a trimeric protomer in solution. Coprecipitation experiments and a quartz crystal microbalance (QCM) demonstrated that gp45-C irreversibly binds to the E. coli membrane. These results indicate that gp45 shows behaviors similar to tail-spike proteins of other phages; however, gp45 did not show significant sequence homology with the other phage tail-spike structures that have been identified.
  Biochimica et Biophysica Acta 09/2010; 1804(9):1738-42. · 4.66 Impact Factor
• Article: Observation of the membrane binding activity and domain structure of gpV, which comprises the tail spike of bacteriophage P2.

  Yasuhiro Kageyama, Masanori Murayama, Takashi Onodera, Seiko Yamada, Harumi Fukada, Motonori Kudou, Kouhei Tsumoto, Yoshiharu Toyama, Syunsaku Kado, Kenji Kubota, Shigeki Takeda
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  ABSTRACT: The P2 phage virion has tail spike proteins beneath the baseplate and uses them to adsorb to the outer membrane of Escherichia coli during the infection process. Previous immunoelectron microscopic studies suggested that the tail spikes are composed of the gene V product (gpV); however, experimental evidence of its membrane binding activity has yet to be reported. In this study, we purified and characterized recombinant full-length gpV and its C-terminal domain. Limited chymotrypsin proteolysis of gpV produced a C-terminal domain composed of Ser86-Leu211. Our experiments demonstrated that the N- and C-terminal domains have very different melting temperatures: 50 and 74 degrees C, respectively. We also found that gpV binds the E. coli membrane via its C-terminal domain. We conclude that the C-terminal domain of gpV is a stable trimer and serves as the receptor-binding domain for the second step in the phage adsorption process.
  Biochemistry 09/2009; 48(42):10129-35. · 3.42 Impact Factor