- Used to differentiate a number of bacteria:
- Staphylococcus (positive) from Streptococcus and Enterococcus (negative)
- Bacillus (positive) from aerotolerant strains of Clostridium (negative)
- Members of the Enterobacteriaceae family (positive) from other Gram-negative bacilli
- Detects the presence of catalase, which catalyzes the conversion of hydrogen peroxide into water and oxygen
- Mix a small sample of bacteria with 3% hydrogen peroxide
- Positive if bubbles appears within 10 seconds
- Negative if no or only a few bubbles
- Bacteria that are catalase positive: staphylococci, Micrococcus, Listeria, Corynebacterium diphtheriae, Burkholderia cepacia, Nocardia, the family Enterobacteriaceae (Citrobacter, E. coli, Enterobacter, Klebsiella, Shigella, Yersinia, Proteus, Salmonella, Serratia), Pseudomonas, Mycobacterium tuberculosis, Aspergillus, Cryptococcus, and Rhodococcus hoagii
- Bacteria that are catalase negative: Streptococcus, Enterococcus, Pediococcus, Leuconostoc, Aerococcus, Gemella
Catalase Positive Organisms
| Stain | Shape | Catalase | |
|---|---|---|---|
| Achromobacter | Gram-negative | bacillus | positive |
| Aeromonas | Gram-negative | bacillus | positive |
| Alcaligenes faecalis | Gram-negative | bacillus | positive |
| Bacillus | Gram-positive | bacillus | positive |
| Brevibacillus | Gram-positive | bacillus | positive |
| Brucella melitensis | Gram-negative | coccobacillus | positive |
| Campylobacter | Gram-negative | bacillus | positive |
| Coagulase-negative staphylococci | Gram-positive | coccus | positive |
| Cronobacter sakazakii | Gram-negative | bacillus | positive |
| Dermabacter hominis | bacillus | positive | |
| Listeria monocytogenes | Gram-variable Gram-positive | bacillus pleomorphic | positive |
| Neisseria | Gram-negative | diplococcus | positive |
| Nocardia | Gram-positive partially acid-fast | bacillus | positive |
| Ochrobactrum | Gram-negative | bacillus | positive |
| Raoultella | Gram-negative | bacillus | positive |
| Raoultella ornithinolytica | Gram-negative | bacillus | positive |
| Staphylococcus aureus | Gram-positive | coccus | positive |
| Stenotrophomonas maltophilia | Gram-negative | bacillus | positive |
| Vibrio | Gram-negative | bacillus | positive |
Catalase Negative Organisms
| Stain | Shape | Catalase | |
|---|---|---|---|
| Enterococcus | Gram-positive | coccus | negative |
| Erysipelothrix rhusiopathiae | Gram-positive | bacillus | negative |
| Leuconostoc | Gram-positive | coccus | negative |
| Neisseria elongata | Gram-negative | bacillus | negative |
| Pediococcus | Gram-positive | coccus | negative |
| Streptococcus | Gram-positive | coccus | negative |
| Streptococcus anginosus group | Gram-positive | coccus | negative |
| Streptococcus mitis | Gram-positive | coccus | negative |
| Streptococcus pneumoniae | Gram-positive | coccus | negative |
| Streptococcus pyogenes | Gram-positive | coccus | negative |
