A single strain (8021) of Neisseria meningitidis, isolated from a child with disseminated meningococcal disease, was found to elaborate two serogroup-specific capsular polysaccharides - Y and W135. The original isolate as well as the progeny of ten single colony sub-isolates each agglutinated with both group Y and group W135 serogrouping antisera. The capsular polysaccharide of strain 8021 contained the chemical constituents of both the W135 and Y capsular polysaccharides in a ratio of about 2.5:1. The patient responded immunologically to both capsular polysaccharides with haemagglutinating antibodies. Analysis by double diffusion in agar revealed that the capsular polysaccharide of strain 8021 contained individual molecules of group W135 and group Y capsular polysaccharides as well as a mosaic molecule containing both antigenic determinants.
The ultrastructural location of the group-specific polysaccharide and the type-specific protein antigens R and X of group B streptococci was studied by means of the direct immunoferritin technique. The group-specific antigen was located on the outer wall layer. The specificity of the reaction was proved by the inhibition of labelling after absorption of the antibody-ferritin conjugate with group B polysaccharide. On the other hand, the demonstration of the polysaccharide was not sterically hindered by protein type antigens. As with group A and C streptococci the group polysaccharide could be localized on both the outer and inner surfaces of isolated walls. The protein antigens R and X were also demonstrated on the wall surface. The specificity of the reaction was ensured by making use of the enzymic sensitivity of these antigens. The location of the R protein on long filaments protruding from the cell surface resembles that of M protein of group A streptococci. In contrast to the group polysaccharide both the R and X protein antigens are localized only on the outer surface of isolated walls.
Morphological aspects of the outgrowth of Bacillus subtilis strain w23 from heat-activated spores were examined by scanning electron microscopy. After 60 min incubation at 37 °C on agar medium, cracks appeared on the spore shells at their equatorial position and vegetative bacteria emerged by breaking open the cracks. In the following 180 min, the bacteria continued to grow without cell separation or the formation of flagella, so that, at 240 min, long filamentous forms of the vegetative bacteria were seen. Cell separation occurred at 300 min and simultaneously the development of flagella was observed. In liquid medium, the vegetative bacteria showed cell separation at an earlier stage (120 min) of outgrowth and flagella were visible at this stage. These results suggested that cell separation and flagella formation were closely related events. The role of autolytic enzymes in cell separation and flagella formation in relation to spore outgrowth is discussed.