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PetriKey

Identification flow

Gram-negative Rods

Lactose fermentation and oxidase branch

  1. Gram-negative rod

    Common intro branch: oxidase status, lactose fermentation, and nonfermenter vocabulary. This is an educational study branch, not a diagnostic or specimen-identification protocol.

    Reference Gram stain

    1. Lactose fermenter

      E. coli is a core lactose-fermenting Enterobacterales anchor in many courses.

      Reference Escherichia coli

    2. Nonfermenter / oxidase-positive

      Pseudomonas is a classic oxidase-positive nonfermenting rod anchor.

      Reference Pseudomonas aeruginosa · Oxidase test