Development of a quantitative immunological assay for the study of spore coat synthesis and morphogenesis.

A quantitative assay employing (125)I-labeled antibody has been developed for Bacillus cereus T spore coat protein. Populations of antibody molecules with various affinities for inner or outer coat can be prepared by selective adsorption to and elution from different coat preparations. Adsorption to and elution from intact spores results in an antibody preparation at least 15 times more reactive to outer coat. This antibody is useful for measuring the time and extent of spore coat maturation, i.e., outer spore coat formation. Rifampin inhibits the increase in content of this coat antigen.