Structural and mutational analyses of the receptor binding domain of botulinum D/C mosaic neurotoxin: Insight into the ganglioside binding mechanism

Nipawan Nuemket, Yoshikazu Tanaka, Kentaro Tsukamoto, Takao Tsuji, Keiji Nakamura, Shunji Kozaki, Min Yao, Isao Tanaka

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Clostridium botulinum type D strain OFD05, which produces the D/C mosaic neurotoxin, was isolated from cattle killed by the recent botulism outbreak in Japan. The D/C mosaic neurotoxin is the most toxic of the botulinum neurotoxins (BoNT) characterized to date. Here, we determined the crystal structure of the receptor binding domain of BoNT from strain OFD05 in complex with 3′-sialyllactose at a resolution of 3.0 Å. In the structure, an electron density derived from the 3′-sialyllactose was confirmed at the cleft in the C-terminal subdomain. Alanine site-directed mutagenesis showed the significant contribution of the residues surrounding the cleft to ganglioside recognition. In addition, a loop adjoining the cleft also plays an important role in ganglioside recognition. In contrast, little effect was observed when the residues located around the surface previously identified as the protein receptor binding site in other BoNTs were substituted. The results of cell binding analysis of the mutants were significantly correlated with the ganglioside binding properties. Based on these observations, a cell binding mechanism of BoNT from strain OFD05 is proposed, which involves cooperative contribution of two ganglioside binding sites.

Original languageEnglish
Pages (from-to)433-439
Number of pages7
JournalBiochemical and biophysical research communications
Volume411
Issue number2
DOIs
Publication statusPublished - 2011 Jul 29
Externally publishedYes

Keywords

  • Botulinum neurotoxin
  • Crystal structure
  • D/C mosaic
  • Ganglioside recognition
  • Receptor binding domain

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Structural and mutational analyses of the receptor binding domain of botulinum D/C mosaic neurotoxin: Insight into the ganglioside binding mechanism'. Together they form a unique fingerprint.

  • Cite this