Biochemical tests

Different metabolic pathways and the constituting enzyme systems are utilized in these tests (in combination with other methods) for typing. More information about the following test methods and about the reactions of the bacteria in some of these test methods are given under the respective test and on the bacteria pages:

• Citrate test, which shows if the bacteria can utilize citrate, as the only carbon source.
  
• Dihydrogensulfide (H₂S) production, which shows if the bacteria can produce dihydrogensulfide from some source of sulfur.
  
• Mixed acid fermentation, which shows if the bacteria can ferment glucose to formic, acetic and lactic acid.
  
• Voges-Proskauer (VP) test, which shows if the bacteria can produce 2,3-butanediol during fermentation of glucose.
  

V (variable) instead of + or -, means that certain strains of the actual bacterial species have the enzyme system, whereas other strains of the same species lack certain enzyme(s) of the system. If the majority of the strains have the actual enzyme system, it is indicated by (+) and if the majority of the strains lack the actual enzyme system, it is indicated by (-).

Uppdated: 2009-08-26.