Genetic and Physiological Control of Protective Antigen Synthesis by Bacillus Anthracis
Abstract
The primary objective of the research is to gain information and to develop genetic systems that will contribute to the development of an improved vaccine for anthrax. Genetic and physiological factors controlling the synthesis and accumulation of protective antigen as well as the two other components of anthrax toxin are being investigated. Attention was concentrated on the following areas during the past year: Spontaneous variation in B. anthracis; Is the presence of a plasmid or prophage related to toxin synthesis; and Genetic exchange systems, isolation of mutants, and chromosomal mapping. Phage CP-51 is an effective generalized transducing phage for B. anthracis, and it is being used for chromosomal mapping. For this purpose a number of auxotrophic mutants of the Weybridge strain have been isolated and characterized. Phage CP-51 is effective also in transferring the tetracycline resistance plasmid, pBC16, among strains of B. cereus, B. thuringiensis, and B. anthracis. pBC16 is being used as a plasmid marker in the Weybridge strain. Variants of the Weybridge strain cured of a large plasmid failed to produce detectable amounts of protective antigen. Such variants retained the original auxotrophic marker of the parent strain, but in addition they demonstrated new nutritional requirements. It is unclear whether the additional nutritional requirements resulted from loss of the plasmid or whether they reflect new chromosomal mutations induced by the curing agents.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1981
- Accession Number
- ADA113729
Entities
People
- Curtis B. Thorne
Organizations
- University of Massachusetts Amherst