Serological relationships among budding, prosthecate bacteria

Abstract

The somatic antigens of 25 strains of budding bacteria were typed and 14 serologically distinct groups were identified, suggesting considerable antigenic diversity among hyphomicrobia. Ten of the groups were represented by a single isolate, 2 contained two isolates, 1 three isolates, and 1 eight isolates. The strains in the largest group of eight isolates each shared at least one common antigen. However, there was also considerable antigenic heterogeneity within this cluster. Serological activity resided in the lipopolysaccharide (LPS) portion of cell walls and also in a heat labile component of Hyphomicrobium neptunium. The amino acid utilizing isolates, H. neptunium and Hyphomonas polymorpha, were serologically unrelated and it is suggested that the two organisms could be grouped as members of the same genus but not the same species.