Urinary tract infections are one of the most frequent bacterial diseases in humans, and Escherichia coli is most often the relevant pathogen. A specific pathotype of E. coli, known as uropathogenic E. coli (UPEC), often causes serious and difficult-to-treat infections of the urinary tract. We propose a new single-tube screening tool that uses an (N) 6 (CGG) 4 primer to generate fingerprint profiles that allow rapid discrimination and epidemiology of this group of bacteria. We found 71 different CGG-PCR profiles among 127 E. coli strains, while enterobacterial repetitive intergenic consensus (ERIC)-PCR of the same group yielded only 28 profiles. Additionally, the (CGG) 4 -based PCR test turned out to be very effective for clustering UPEC strains exhibiting multiple virulence genes and usually belonging to the B2 phylogenetic group, and it separated these strains from E. coli strains lacking most of the UPEC-specific virulence factors. Since the reproducibility of the CGG-PCR screen is higher than that of ERIC-PCR, our test should be a valuable means of increasing the discriminatory power of current UPEC typing schemes.Gram-negative rods are the major etiological agents in urinary tract infections (UTIs) in humans, and Escherichia coli comprises most of these agents (20,30,32,34,38,42). In some cases, UTI treatment is difficult because of persistent recurrences. Furthermore, UTIs are often asymptomatic at the beginning of the infection process. Particular phenotypic features of uropathogenic E. coli (UPEC) strains facilitate their persistence in urinary tracts and differentiate them from the other pathogenic and commensal E. coli strains (7,29,31). UPECspecific virulence factors (VFs), which are mostly adhesins (P and S fimbriae), toxins (cytotoxic necrotizing factor type 1, ␣-hemolysin), bacteriocin (uropathogenic-specific protein), and siderophores (aerobactin and yersiniabactin), are important for colonization of the urinary tract (7,8,27). Also, type 1 fimbriae and afimbrial adhesin I are beneficial in this type of infection. Additionally, phylogenetic analyses have revealed that UPEC strains differ substantially from other E. coli strains (2, 10, 43). Pathogenic E. coli strains, including UPEC strains, belong mainly to groups B2 and D (2,5,14).In the case of E. coli, 16S rRNA gene sequence analysis, phylogenetic studies, and VF profiles are valuable for detailed genetic identification (4,5,11,35). PCR-based methods are very efficient, inexpensive, and rapid (44). Previously, two distinct prokaryotic repetitive elements were used for gram-negative enterobacterial strain discrimination: repetitive extragenic palindromic (REP) elements and enterobacterial repetitive intergenic consensus (ERIC) sequences (16,37,40). Because the ERIC-PCR band patterns were less complex than the REP-PCR band patterns, differences within the analyzed species were easier to distinguish with ERIC-PCR.The goals of this work were to develop a novel genetic test (termed CGG-PCR) for the differentiation and epidemiological investigation o...

Escherichia coli and Proteus mirabilis are important urinary tract pathogens. The constant increase in the antibiotic resistance of clinical bacterial strains has become an important clinical problem. The aim of this study was to compare the antibiotic resistance of 141 clinical (Sweden and Poland) and 42 laboratory (Czech Republic) P.mirabilis strains and 129 clinical (Poland) uropathogenic E. coli strains. The proportion of unique versus diverse patterns in Swedish clinical and laboratory P. mirabilis strain collections was comparable. Notably, a similar proportion of unique versus diverse patterns was observed in Polish clinical P. mirabilis and E. coli strain collections. Mathematical models of the antibiotic resistance of E. coli and P. mirabilis strains based on Kohonen networks and association analysis are presented. In contrast to the three clinical strain collections, which revealed complex associations with the antibiotics tested, laboratory P. mirabilis strains provided simple antibiotic association diagrams. The monitoring of antibiotic resistance patterns of clinical E. coli and P. mirabilis strains plays an important role in the treatment procedures for urinary tract infections and is important in the context of the spreading drug resistance in uropathogenic strain populations. The adaptability and flexibility of the genomes of E. coli and P.mirabilis strains are discussed.

Antibiotic therapy and its consequences in bacterial and human aspects are widely investigated. Despite this, the emergence of new multidrug resistant bacteria is still a current problem. The scope of our work included the observation of changes among uropathogenic Escherichia coli strains after the treatment with a subinhibitory concentration of different antibiotics. The sensitive strains with or without virulence factors were incubated with amoxicillin, ciprofloxacin, gentamycin, or tobramycin. After each passage, the E. coli derivatives were compared to their wild types based on their susceptibility profiles, virulence genes, biofilm formations and the fingerprint profiles of PCR products amplified with using the (N)(6)(CGG)(4) primer. It turned out that antibiotics caused significant changes in the repertoire of bacterial virulence and biofilm formation, corresponding to acquired cross-resistance. The genomic changes among the studied bacteria were reflected in the changed profiles of the CGG-PCR products. In conclusion, the inappropriate application of antibiotics may cause a rapid rise of Multidrug Resistant (MDR) strains and give bacteria a chance to modulate their own pathogenicity. This phenomenon has been easily observed among uropathogenic E. coli strains and it is one of the main reasons for recurrent infections of the urinary tract.

The spreading mechanisms of antibiotic resistance are related to many bacterial and environment factors. The overuse of antibiotics is leading to an unceasing emergence of new multidrug resistant strains. This problem also concerns uropathogenic Escherichia coli strains, which is the most common pathogen causing urinary tract infections. The aim of this study was the genetic analysis of antibiotic resistance in comparison to the phenotypic background of E. coli strains. The characterized collection of E. coli strains isolated 10 years ago from the urine samples of patients with urinary tract infections was used for antimicrobial susceptibility testing (the disc diffusion method) and analysis of antibiotic resistance genes (PCR reaction, sequencing). Additionally, the presence of ESBL strains was analyzed. Fourteen genes were associated with resistance to beta-lactams, aminoglycosides, sulfonamides and quinolones. The genetic analysis revealed that blaTEM-1 and sul2 were present in almost all of the studied strains. Other drug-resistance genes were very rare or non-existent. Otherwise, the phenotypic resistance to fluoroquinolones was well correlated with the genotypic background of the studied bacteria. The presence of particular genes and specific mutations indicate a high bacterial potential to multidrug resistance. On the other hand, it needs to be emphasized that the standard disk diffusion test for the routine antimicrobial susceptibility analysis is still the best way to estimate the current situation of bacterial drug-resistance.