Bacterial spores as antigens

Serological studies of Clostridium botulinum type E and related organisms. II. Serology of spores

Pure spore antigens for the immunization of rabbits were prepared by enzymic digestion of vegetative components and separation of the cleaned spores in polyethylene glycol. Spore antisera were prepared to strains representative of toxigenic Clostridium botulinum type E; nontoxigenic boticin E-producing variants; nontoxigenic nonproducers of boticin E; nontoxigenic "atypical" strains, which differ somewhat from C. botulinum type E in their physiology; C. botulinum types A and B; and C. bifermentans. They were tested against these and additional strains representative of the above groups, other types of C. botulinum, and other Clostridium species. There was no evidence of agglutination of flagellar or somatic antigens of vegetative cells by these antisera. Agglutination and agglutinin absorption tests showed common antigens among toxigenic type E strains and nontoxigenic variants, both producers and nonproducers of boticin E. Some nontoxigenic "atypical" strains varied in their ability to be agglutinated by type E antisera, and others did not agglutinate at all. Of those atypical strains that were not agglutinated, one was agglutinated by C. bifermentans antiserum. Antisera prepared against C. botulinum types A and B and C. bifermentans did not agglutinate the spores of type E or its variants nor share antigens common to each other. Similarly, antisera to type E, its nontoxigenic variants, and nontoxigenic atypical strains did not agglutinate other C. botulinum types or any other Clostridium species investigated.

Antigen changes during spore formation in Bacillus cereus

Baillie, Ann (University of Glasgow, Glasgow, Scotland), and John R. Norris. Antigen changes during spore formation in Bacillus cereus. J. Bacteriol. 87:1221-1226. 1964.-Ultrasonic extracts of Bacillus cereus cells harvested at different stages in spore formation were analyzed by immunoelectrophoresis with antisera prepared by injecting similar extracts into rabbits. Seven antigens resistant to heating at 80 C for 10 min were detected in extracts of young vegetative cells, and there were at least eight additional thermolabile antigens present at this stage. During spore formation, many of the thermolabile antigens disappeared from the cells and new antigens could be detected. Mature spores contained four of the heat-resistant antigens present in young vegetative cells and an additional five heat-resistant antigens. Only three thermolabile antigens were detected in spore extracts.

The protein crystals of Bacillus thuringiensis Berliner

On sporulation the cells of the insect pathogen Bacillus thuringiensis contain at one end a spore and at the other end a diamond shaped crystal. A method has been developed for the separation of the alkali dispersible crystal material from spores, vegetative cell debris, and their alkali soluble components. Two methods are given for the preparation of suspensions of intact crystals free from other material. One method depends on the mechanical disruption of the spores, the other on germination and autolysis of the spore contents. After either method clean suspensions of crystals were obtained by washing and differential centrifugation. The purest preparations have yielded a substance precipitable with trichloracetic acid, possessing the ultraviolet absorption characteristics of protein, containing over 17% nitrogen and at least 17 amino acids, but no phosphorus. Examination of the crystals with the electron microscope has shown that they have a tetragonal form and possess some fine structures; no virus particles were found in alkali dispersed crystal protein.

Spore structure as revealed by thin sections

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The structure of spores as revealed by mechanical disruption

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