What is the Difference Between Proteus Mirabilis and Vulgaris?

Proteus mirabilis and Proteus vulgaris are two distinct species within the genus Proteus, which can be differentiated based on their indole production and other characteristics. The main differences between Proteus mirabilis and Proteus vulgaris include:

1. Indole production: Proteus mirabilis is indole-negative, meaning it cannot produce indole from tryptophan, while Proteus vulgaris is indole-positive and can produce indole.
2. Association with urinary tract infections: Proteus mirabilis is the most frequent Proteus species associated with urinary tract infections, while indole-positive Proteus vulgaris is more often resistant to ampicillin and may also cause urinary tract infections.
3. Hydrophobicity: Proteus mirabilis strains seem to be more homogeneous in terms of hydrophobicity, while Proteus vulgaris strains show more heterogeneity.
4. Virulence factors: Differences in haemolysin production, cell invasiveness, and experimental virulence in a mouse model have been observed between the two species. These differences might explain why Proteus mirabilis is more common in human urinary tract infections than Proteus vulgaris.

In summary, Proteus mirabilis and Proteus vulgaris can be distinguished based on their indole production, association with urinary tract infections, hydrophobicity, and virulence factors. Proteus mirabilis is more commonly associated with urinary tract infections, while Proteus vulgaris is more resistant to ampicillin and less commonly involved in such infections.

Comparative Table: Proteus Mirabilis vs Vulgaris

Here is a table comparing the differences between Proteus mirabilis and Proteus vulgaris:

Both Proteus mirabilis and Proteus vulgaris are rod-shaped, gram-negative bacteria that belong to the genus Proteus and are catalase positive. They can cause urinary tract infections in humans, and their infections are treated with specific antibiotics. However, Proteus mirabilis is more frequently associated with urinary tract infections and has a negative indole test, while Proteus vulgaris is less frequently associated with urinary tract infections and has a positive indole test. Additionally, the swarming motility of Proteus mirabilis is more visible than that of Proteus vulgaris.