SEROLOGY OF THE MIMA-HERELLEA GROUP AND THE GENUS MORAXELLA.

Mitchell, Paul D. (West Virginia University Medical Center, Morgantown), and Robert G. Burrell. Serology of the Mima-Herellea group and the genus Moraxella. J. Bacteriol. 87:900-909. 1964.-The identity of organisms which have been assigned to the Mima-Herellea group of the tribe Mimeae and their taxonomic position are uncertain. In considering the possible relationship of the Mima-Herellea group to the genus Moraxella, the approach used was the isolation and identification of representative antigenic constituents of strains designated Mima polymorpha, M. polymorpha var. oxidans, Herellea vaginicola, Moraxella lwoffi, M. liquefaciens, M. non-liquefaciens, and Bacterium anitratum. Cell-free extracts of sonically disrupted cells were used in these studies, and the precipitinogens derived by this method were considered to be of capsular and somatic origin. Identity among the strains was established by immunodiffusion, with immune sera and antigenic extracts. Heterologous and homologous reactions were performed with adsorbed and unadsorbed sera to verify the cases of identity. In every instance of homologous reaction, at least five distinct antigen-antibody systems were discernible within the Mima-Herellea group. However, as evidenced by heterologous studies, the demonstrable antigenic composition varied among the species and, in some instances, among the strains. M. polymorpha var. oxidans appeared to be serologically distinct from H. vaginicola and M. polymorpha, whereas strains of the latter two organisms were theorized to be closely related serologically. Serological cross-reactions in heterologous studies and reciprocal adsorption tests revealed the existence of a serological relationship between members of the Mima-Herellea group and the genus Moraxella. A tentative scheme of identity is postulated on the basis of these crossreactions and cultural and biochemical reactions among the designated strains of Herellea, Mima, Moraxella, and Bacterium.