The use of repetitive element PCR fingerprinting (rep-PCR) for genetic subtyping of German field isolates of Paenibacillus larvae subsp larvae

Studies using the repetitive element PCR fingerprinting technique (rep-PCR) revealed that BOX A1R-, MBO REP1- and ERIC-primers reproducibly generate distinctive DNA fingerprints from Paenibacillus larvae subsp. larvae. Four different genetic subtypes of P. larvae were identified in Germany using the three primers. Correlating the results from genetic and morphological subtyping, the flat and transparent morphotype could be assigned to one genetic group. Geographic evaluation of our results demonstrated that the different genetic subtypes appeared in clusters correlating with different outbreaks of American foulbrood. Taken together, our results indicated that rep-PCR performed with a combination of BOX A1R- and MBO REP1- primers will be an effective tool for establishing a molecular epidemiology of P. l. larvae.