Identification by 16S rDNA fragment amplification and determination of genetic diversity by random amplified polymorphic DNA analysis of Pasteurella pneumotropica isolated from laboratory rodents

Pasteurella pneumotropica is an opportunistic bacterium frequently isolated from colonies of various laboratory rodents. Identification of this specie s, including its differentiation into two distinct biotypes (Jawetz and Hey l), is usually based on the use of conventional bacteriologic methods, In t his study, a 16S rDNA fragment amplification procedure was developed for us e as an alternative method for identification and differentiation of P, pne umotropica. Polymerase chain reaction (PCR) products were two distinctive f ragments of 937 and 564 bp specific for biotypes Jawetz and Heyl, respectiv ely. Specificity of PCR products could be achieved by EcoRI cleavage, leadi ng to 596 plus 341-bp and 346 plus 218-bp fragments for each of the amplifi cation products. Use of this procedure confirmed identification of 34 field isolates and allowed definitive identification of some strains that could not have been done by use of bacteriologic examinations. Field isolates sub jected to random amplified polymorphic DNA (RAPD) analysis had high genetic diversity among biotype Jawetz strains in contrast to biotype Heyl strains . In conclusion RAPD could represent an additional means for identification of ambiguous strains of biotype Heyl and a valuable epidemiologic tool for identification of biotype Jawetz strains of P. pneumotropica.