Studies on a Collection of Gram-Negative Bacterial Strains Showing Resemblance to Moraxellae: Examination by Conventional Bacteriological Methods

A collection of 36 gram-negative bacterial strains, showing some resemblance to moraxellae and possibly belonging to Moraxella or related genera, was examined by a number of conventional tests in three laboratories by members of the ICSB Subcommittee on the Taxonomy of Moraxella and Allied Bacteria. Eight of the strains were oxidase negative and could be classified as belonging to Acinetobacter. Of the 28 oxidase-positive strains, two were yellow-pigmented cocci, but differed markedly from neisseriae. A group of 11 rod-shaped strains, also pigmented to a greater or lesser extent, appeared related to Flavobacterium. Four unpigmented, mesophilic strains differed sufficiently to be unlikely members of Moraxella. Nine unpigmented psychrophilic strains, including two strains of Thornley's Phenon 3, showed similarities to moraxellae, although most of them oxidized aldose sugars like acinetobacters. Further taxonomic studies of the psychrophilic group will be of particular interest. The strains described by Bijsterveld (1970) and by Sutton et al. (1972) appeared to be nearly identical, but differed from moraxellae sufficiently to be unlikely members of Moraxella.