Which presumptive test is used for the identification of Pseudomonas species?

The identification of Pseudomonas species is heavily reliant on their metabolic characteristics and physiological aspects. The oxidase test is particularly important as many Pseudomonas species are oxidase positive, which distinguishes them from several other Gram-negative bacteria. Additionally, the oxidation-fermentation glucose tests (both open and sealed) help determine whether the organism can oxidize or ferment carbohydrates, which is pivotal in identifying Pseudomonas, as they primarily oxidize glucose rather than ferment it.

Testing for motility is also crucial because Pseudomonas species are typically motile due to their flagella, and observing pigment production can further confirm their identity, as certain Pseudomonas species produce distinctive pigments that are characteristic of the genus. This combination of tests makes the first option comprehensive and effective for presumptively identifying Pseudomonas species. Each of these tests provides a piece of the puzzle, demonstrating the organism's metabolic profile that aligns with the characteristics typical of Pseudomonas.