What is the Difference Between Klebsiella Oxytoca and Klebsiella Pneumoniae

The main difference between Klebsiella oxytoca and Klebsiella pneumoniae is that K. oxytoca is indole positive whereas K. pneumoniae is indole negative.

K. oxytoca and K. pneumoniae are two closely-related Gram-negative, rod-shaped bacteria. However, both species cause infections in humans.

Key Areas Covered

1. What is Klebsiella Oxytoca
   • Definition, Characteristics, Importance
2. What is Klebsiella Pneumoniae
   • Definition, Characteristics, Importance
3. Similarities Between Klebsiella Oxytoca and Klebsiella Pneumoniae
   • Outline of Common Features
4. Difference Between Klebsiella Oxytoca and Klebsiella Pneumoniae
   • Comparison of Key Differences             

Key Terms

Klebsiella Pneumoniae, Klebsiella Oxytoca

What is Klebsiella Oxytoca

K. oxytoca is a Gram-negative, rod-shaped bacterium, closely-related to K. pneumoniae. In contrast to K. pneumoniae, K. oxytoca is indole positive, which is the most significant feature of this bacterium. Meanwhile, indole test is a biochemical test for bacteria species. It determines the ability of bacteria to convert tryptophan into indole. Tryptophanase is the set of enzymes involved in the conversion. A positive result indicates the presence of red or red-violet color in the surface alcohol layer of the broth.

Figure 1: K. oxytoca

Furthermore, the ability to grow in melezitose is one of the other growth characteristics of K. oxytoca. K. oxytoca is a diazotroph that colonizes in plant hosts to undergo atmospheric nitrogen fixation. Plants can use this nitrogen as a nutrient. Bacteria adhere strongly to root hairs, and less strongly to the surface of the zone of elongation and root cap mucilage. In addition, K. oxytoca belongs to the family Enterobacteriaceae and they are capable of acquiring antibiotic resistance.          

What is Klebsiella Pneumoniae

K. pneumoniae is a Gram-negative, non-motile bacteria that is rod-shaped. It is a facultative anaerobic bacterium that undergoes lactic acid fermentation. K. pneumoniae occurs in the normal flora of the mouth, skin, and intestine. It causes destructive changes to the human and animal lungs resulting in bloody, brownish, or yellow colored jelly-like sputum. Under anaerobic conditions, K. pneumoniae that lives in the soil fixes nitrogen. Therefore, this bacterium increases crop yield.

Figure 2: K. Pneumoniae

Moreover, this bacterium is the etiological factor for pneumonia seen especially in immunocompromised individuals. In addition to pneumonia, Klebsiella can also cause infections in the urinary tract, lower biliary tract, and surgical wound sites. Therefore, the range of clinical diseases of K. pneumoniae includes pneumonia, thrombophlebitis, urinary tract infection, cholecystitis, diarrhea, upper respiratory tract infection, wound infection, osteomyelitis, meningitis, bacteremia, and sepsis.

Similarities Between Klebsiella Oxytoca and Klebsiella Pneumoniae

• K. oxytoca and K. pneumoniae are two species of the genus Klebsiella.
• They are non-motile, aerobic, and facultatively anaerobic, Gram-negative rods.
• Both types of bacteria are diazotrophs that undergo nitrogen fixation.
• Furthermore, Klebsiella spp. are amongst the most common causes of a variety of community-acquired and hospital-acquired infections.

Difference Between Klebsiella Oxytoca and Klebsiella Pneumoniae

Definition

K. oxytoca refers to a Gram-negative, rod-shaped bacterium that is closely related to pneumoniae, of which the main distinguishing feature is being indole-positive, while K. pneumoniae refers to a Gram-negative, non-motile, encapsulated, lactose-fermenting, facultative anaerobic, rod-shaped bacterium.

Indole Test

K. oxytoca is indole positive while K. pneumoniae is indole negative.

Growth

Moreover, K. oxytoca is able to grow on melezitose, but not 3-hydroxybutyrate. Meanwhile, K. pneumoniae grows on MacConkey agar.

Type of Fermentation

Furthermore, K. oxytoca undergoes ethanol fermentation while K. pneumoniae undergoes lactic acid fermentation.

Conclusion

In brief, K. oxytoca and K. pneumoniae are two closely-related species of the genus Klebsiella. Both are Gram-negative, aerobic, and facultative anerobic bacteria. Moreover, they are rod-shaped bacteria that are nonmotile. K. oxytoca undergoes ethanol fermentation while K. pneumoniae undergoes lactic acid fermentation. However, K. oxytoca is indole positive and K. pneumoniae is indole negative. Therefore, the main difference between K. oxytoca and K. pneumoniae is the indole test.

References:

1. “Klebsiella Oxytoca.” Wikipedia, Wikimedia Foundation, 22 Oct. 2021
2. “Klebsiella Pneumoniae.” Wikipedia, Wikimedia Foundation, 1 Oct. 2022.

Image Courtesy:

1. “Klebsiella oxytoca” By Riraq25 – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Klebsiella pneumoniae 01” By CDC – Own Work (Public Domain) via Commons Wikimedia