The oxidase test is a test used in catalase).
- OX+ 1.1
- OX- 1.2
- Procedures 2
- References 3
- External links 4
Strains may be either oxidase-positive (OX+) or oxidase-negative (OX-).
The Pseudomonadaceae are typically OX+
Also Legionella pneumophila is oxidase-positive.
OX- normally means the bacterium does not contain cytochrome c oxidase and, therefore, either cannot use oxygen for energy production with an electron transfer chain or employs a different cytochrome for transferring electrons to oxygen.
Enterobacteriaceae are typically OX-.
- Wet each disk with about four inoculating loops of deionized water.
- Use a loop to aseptically transfer a large mass of pure bacteria to the disk.
- Observe the disk for up to three minutes. If the area of inoculation turns dark-blue to maroon to almost black, then the result is positive. If a color change does not occur within three minutes, the result is negative.
In alternative manner, live bacteria cultivated on trypticase soy agar plates may be prepared using sterile technique with a single-line streak inoculation. The inoculated plates are incubated at 37 °C for 24–48 hours to establish colonies. Fresh bacterial preparations should be used. After colonies have grown on the medium, 2-3 drops of the reagent DMPD are added to the surface of each organism to be tested.
- A positive test (OX+) will result in a color change violet to purple, within 10–30 seconds.
- A negative test (OX-) will result in a light-pink or absence of coloration.
- "Oxidase Test and Modified Oxidase Test". Retrieved 2008-11-07.
- . Isenberg HD, editor. Clinical Microbiology Procedures Handbook. American Society for Microbiology; 2004. p. 3.3.2-18.104.22.168
- MacFaddin JF, editor. Biochemical Tests for Identification of Medical Bacteria. 3rd ed. Philadelphia:Lippincott Williams and Wilkins; 2000. p. 363-7
- Farmer JJ, Fanning GR, Huntley-Carter GP, et al. (May 1981). "Kluyvera, a new (redefined) genus in the family Enterobacteriaceae: identification of Kluyvera ascorbata sp. nov. and Kluyvera cryocrescens sp. nov. in clinical specimens". J. Clin. Microbiol. 13 (5): 919–33.
- Oxidase test video
- Oxidase Test Procedure