Unusual fermentative, gram-negative bacilli isolated from clinical specimens. II. Characterization of Aeromonas species.

Morphological and physiological characterization of 12 Aeromonas strains isolated from clinical specimens demonstrated several important diagnostic features. These included polar arrangement of the flagella; production of oxidase, deoxyribonuclease, amylase, gelatinase, and lipase; lack of ornithine decarboxylase; and sensitivity to polymyxin. Awareness of these features should result in more frequent differentiation of aeromonads from the physiologically similar members of the genus Plesiomonas and the late- or non-lactose-fermenting species of Enterobacteriaceae.