Strain typing of isolates allows to compare and differentiate strains of the same species. For this purpose we use specific PCR techniques.

Typical applications for strain typing are:

  • confirming the identity of production strains
  • confirming the identity of reference strains
  • identifying the source(s) of contaminating microorganisms
  • grouping of isolates / phylogenetic analysis


Depending on the microorganism different methods are used for strain typing:

  • bacteria: DAF-PCR or ERIC-PCR
  • eucaryotes: microsatellite PCR

In addition to the test isolate(s) a defined reference isolate is required. The PCR products are separated on acrylamid gels (v. fig.). The band pattern is analysed with a specific program for densitometric analyses. Additionally for several isolates a phylogenetic tree may be generated to visualize the genetic similarities.

Additional information may be found here: