After establishing that, like types B and E toxins, type A botulinus toxin contains only one residue of cysteine per molecule, chemical modification studies were carried out showing that sulfhydryl-specific reagents like p-chloromercuribenzoate (PCMB) and N-(4-dimethyl-amino-3,5-dinitrophenyl) maleimide (DDPM) cause a marked decrease in toxicity.
Types A, B and E toxins were reacted with DDPM and a labelled peptide was obtained from the tryptic digest of each of the toxins. The quantitative amino acid analyses of these three peptides were remarkably similar. Sequence analyses showed that a sequence
ala-glu-ser-cys-ser-asp-ser is common to all three DDPS-peptides.
Type B botulinus toxin does not enzymatically alter acetylcholine
in order to cause flaccid paralysis.
It is postulated that the three thiol-containing peptides isolated contain all or part of a postulated active site common to each of types A, B and E botulinus toxins. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate
| Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/37449 |
| Date | January 1966 |
| Creators | Van Alstyne, Diane |
| Publisher | University of British Columbia |
| Source Sets | University of British Columbia |
| Language | English |
| Detected Language | English |
| Type | Text, Thesis/Dissertation |
| Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
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