Morphological and Biochemical Differentiation of Achromobacter and Moraxella (Debord's Tribe Mimeae )

Abstract

To determine the most useful laboratory tests for the differentiation of Achromobacter anitratus, Achromobacter lwoffii , and Moraxella duplex (DeBord's tribe Mimeae ), 157 strains of these bacteria, isolated from clinical specimens, were examined for their morphological and biochemical characteristics. There were several differences between these nonfermentative, gram-negative diplococci: Moraxella was nonglucolytic in either infusion base or synthetic base, oxidase-positive, and sensitive to penicillin, whereas Achromobacter produced variable carbohydrate activity, and was oxidase-negative and resistant to penicillin. A. anitratus was distinguished from A. lwoffii in that the former utilized infusion media containing either glucose or 10% lactose, whereas the latter did not. Both species utilized the same carbohydrates in a chemically defined medium, although the latter acted more sluggishly.