Which test would NOT be suitable for identifying Neisseria species?

The urease test is not suitable for identifying Neisseria species because members of this genus do not produce the enzyme urease, which is responsible for hydrolyzing urea into ammonia and carbon dioxide. A negative urease result would not provide any valuable information specifically related to identifying Neisseria, as this characteristic is not relevant to their identification.

In contrast, the oxidase test is important for identifying Neisseria species, as they are oxidase-positive. The beta-lactamase test can help determine the antibiotic resistance profile of Neisseria species, particularly in clinical isolates. Gram staining is also crucial for this identification since Neisseria species are Gram-negative cocci, and the staining will reveal their characteristic morphology. Thus, using the urease test would not yield useful results in the context of Neisseria identification, making it the least suitable option.