Tandem Tetramer-Based Microsatellite Fingerprinting for Typing of Proteus mirabilis Strains

Abstract

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.Proteus spp. are mobile gram-negative bacteria common in both the natural environment and animal or human intestinal tracts. Proteus spp. are also known etiologic agents for meningitis and numerous bacteremias (8,(20)(21)(22)(23)43). Urinary tract infections are among the most frequent bacterial infections (19), and Proteus mirabilis strains are one of the most common causes of urinary tract infections (7%), third after Escherichia coli (52%) and Enterococcus spp.(12%) (11). Such infections occur commonly among patients with structural defects of the urinary tract (6,38,39). The presence of P. mirabilis rods within a urease-induced bladder stone matrix was visualized recently (24). Moreover, some results suggest a possible etiopathogenic role of P. mirabilis in rheumatoid arthritis (9, 31), and some nosocomial transmission events have been reported (31). Because of the increasing spread and clinical significance of P. mirabilis rods (13,15,30,31,32), studies of effective methods for epidemiological investigations are of great importance.Out of the numerous types of simple sequence repeats proposed as tools for very sensitive bacterial fingerprinting (25,27,48,50,51,54), many microsatellites have been described as being useful for microbial differentiation, especially below the level of species (1,10,26,28,33,34,47,48,49,53).Most of the molecular fingerprinting methods applied for the differentiation of Proteus (35,36,44), however, are not sensitive enough for more detailed interstrain differentiation. In particular, no specific method allowing for P. mirabilis differentiation, especially below the serotype level, has been described so far.In this study, we have focused on microsatellite-based methods supplying patterns specific for particular P. mirabilis strains. The aim of the study was to verify how effective microsatellites are for P. mirabilis fingerprinting; in particular, we examined whether tandem tetramer-based PCR is applicable to Proteus strain differentiation or typing...

Comparison of PCR-based molecular markers for the characterization of Proteus mirabilis clinical isolates

“…Our data corroborate the conclusions reported by Cieslikowski et al [19], who showed (GACA) 4 and (CAAT) 4 to be informative primers, and indicates that other primers, such as (AC) 8 T and (AG) 8 A, could be useful in P. mirabilis studies. However, despite the large size of the primers, ISSR markers applied to P. mirabilis gave low reproducibility, and were not suitable for identification to the genus level.…”

“…Studies on the molecular epidemiology of infection due to Proteus species have employed a variety of methods, including ribotyping, PFGE, RAPD, and tandem-repeat microsatellite fingerprinting [14][15][16][17][18][19]. We showed that RAPD markers vary in their discriminatory ability.…”

“…RAPD, a PCR-based method, has been used with success in the identification of clinical isolates of P. mirabilis [17] and P. penneri [18]. More recently, the tandem tetramer microsatellites (GACA) 4 and (CAAT) 4 , also known as intergenic single sequence repeats (ISSR), have given a high degree of discrimination for P. mirabilis [19].…”

Chemometric analysis of attenuated total reflectance infrared spectra of Proteus mirabilis strains with defined structures of LPS

“…The isolates studied have defined OPS structure, and they showed a degree of phenotypic diversity. 23,29 Preprocessing of the ATR FT-IR spectra was required before modeling. The Savitzky–Golay filter was applied to reduce noise, and the first derivative was considered.…”

Peculiarities of <I>Alteromonas macleodii</I> strains reflects their deep/surface habitation rather than geographical distribution

“…Prokaryotic dispersed repeat elements, such as REP, ERIC and BOX motifs, are perspective for molecular typing purposes: low level of intraspecies variability among Polynucleobacter inhabiting freshwater lake in Alps and high genomic heterogeneity among A. macleodii strains isolated from the Urania basin were revealed with their help (Hahn et al, 2005;Sass et al, 2001). Short nucleotide repeats, another class of bacterial repeats, have also been used for strain differentiation of some microorganisms (Ablordey et al, 2007;Cieslikowski et al, 2003). We used DNA-markers (short repeated nucleotide sequences) that are high polymorphic and allow evaluation of genome variability to study intraspecies genomic heterogeneity of A. macleodii.…”