Source: Fondazione Diasorin
Level of schooling: high
Classrooms: 3, 4, 5
Date: 14-10-2020
The cytochrome enzyme oxidase is a protein found in mitochondria membranes and it plays a crucialrole in cellular respiration. Not all bacteria have it and, using a simple colorimetric test based on a redox reaction, it is possible to distinguish bacteria that have the enzyme from bacteria that do not.
This test is also used to differentiate among gram-negative bacteria those belonging to the Pseudomonas genus (positive to testing) from enterobacteria such as E.coli, Bacillus subtilis and others that are negative to testing.
This experimental activity, which makes it possible to introduce concepts linked to bacterial metabolism and biochemistry, can be performed in a school microbiology laboratory that has basic instruments such as, for example, a laminar flow hood.
Download the test protocol to perform the oxidase test on various bacterial species!
