Study of Toxic and Antigenic Structures of Botulinum Neurotoxins

Abstract

The neurotoxin (NT) from type B (strain 657) was partially sequenced (44 residues from light chain and 26 residues from heavy chain). Significant sequence homology between this type B botulinum and tetanus NTs are now evident. A second procedure was developed to enzymatically cleave the heavy chain of type A NT into two halves: one of these fragments was partially sequenced. Secondary structures of types A and E NT in terms of alpha helix and Beta sheet contents were determined. Changes in conformation (hydrophobicity) were detected when single chain type E NT was nicked to the dichain form. Roles of i) Lys residues in types A and B NT, and ii) Tyr residues in types A, B and E NT were studied based on chemical modification and quantitative assay of amino acid modification, toxicity and change in serological activity. Type B NT completely detoxified following modification of Tyr residues was a good immunogen (second generation toxoid). Keywords: Amino acid sequence.

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Document Details

Document Type
Technical Report
Publication Date
Mar 20, 1987
Accession Number
ADA202890

Entities

People

  • B. R. Dasgupta

Organizations

  • University of Wisconsin–Madison

Tags

DTIC Thesaurus Topics

  • Amino Acids
  • Antibodies
  • Classification
  • Demographic Cohorts
  • Health
  • Health Services
  • Immune Serums
  • Medical Personnel
  • Proteins
  • Public Health
  • Security
  • Sequences
  • Terminals
  • Therapy
  • Toxicity
  • Toxins
  • Vaccines

Fields of Study

  • Biology

Readers

  • Molecular and Cellular Biochemistry