Role of Sulfhydryl Groups in the Activity of Type A Botulinum Toxin,
Abstract
Both crystalline botulinum toxin, type A (molecular weight 900,000) and a form of lower molecular weight (approx. 130,000) derived from it have four -SH groups and approximately one disulfide bridge per 100,000 grams of protein. Both forms were increasingly inactivated over a 24-hour period to one-tenth of the original toxicity by p-mercuribenzoate, but iodacetamide caused a smaller reduction and N-ethylmaleimide had no effect at all. Reversal of the p-mercuribenzoate inactivation by reduced glutathione could not be achieved. It is concluded that reaction of -SH groups may affect conformational stability of botulinum toxin, but these groups are not an integral part of its active center. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1970
- Accession Number
- AD0866922
Entities
People
- John N. Knox
- Leonard Spero
- William P. Brown