Tandem tetramer-based microsatellite fingerprinting for typing of Proteus mirabilis strains.

Two microsatellite tandem repeated tetramers, (GACA)(4) and (CAAT)(4), were used for Proteus mirabilis strain differentiation. The microsatellite-based PCR tests were applied for the examination of interstrain diversity for 87 P. mirabilis strains. Forty-six of the investigated strains were clinical isolates (5 were hospital isolates and 39 were outpatient clinic isolates); 42 strains were derived from the Kauffmann-Perch collection of laboratory strains. Fingerprinting done with the tetramers had a high discrimination ability [0.992 and 0.940 for (GACA)(4) and (CAAT)(4), respectively]. The distributions of clinical isolates among well-defined laboratory strains, determined by numerical analysis (unweighted pair-group method with arithmetic averages; Dice similarity coefficient), proved their genetic similarity to reference strains in the Kauffmann-Perch collection. This analysis also indicated that it is possible to estimate some phenotypic properties of P. mirabilis clinical isolates solely on the basis of microsatellite fingerprinting.