The adherence of bladder uroepithelial cells, subsequent expression, and regulation of type 1 fimbrial genes (key mediator of attachment) in clinical multidrug-resistant uropathogenic Escherichia coli (MDR-UPECs) isolated from individuals with asymptomatic bacteriuria (ABU) remain unexplored till date. Therefore, this study aimed to investigate the underlying molecular mechanisms associated with the adherence of clinical MDR-ABU-UPECs to human a uroepithelial cell line (HTB-4), both in the absence and presence of D-Mannose. These investigations focused on phase variation, expression, and regulation of type 1 fimbriae and were compared to a prototype ABU-strain (E. coli 83972) and symptomatic MDR-UPECs. Discordant to the ABU prototype strain, MDR-ABU-UPECs exhibited remarkable adhesive capacity that was significantly reduced after D-mannose exposure, fairly like the MDR symptomatic UPECs. The type 1 fimbrial phase variation, determined by the fim switch analysis, asserted the statistically significant incidence of "both OFF and ON" orientation among the adherent MDR-ABU-UPECs with a significant reduction in phase-ON colonies post-D-mannose exposure, akin to the symptomatic ones. This was indicative of an operative and alternating type 1 fimbrial phase switch. The q-PCR assay revealed a coordinated action of the regulatory factors; H-NS, IHF, and Lrp on the expression of FimB and FimE recombinases, which further controlled the function of fimH and fimA genes in ABU-UPECs, similar to symptomatic strains. Therefore, this study is the first of its kind to provide an insight into the regulatory crosstalk of different cellular factors guiding the adhesion of ABU-UPECs to the host. Additionally, it also advocated for the need to accurately characterize ABU-UPECs.

• Klíčová slova
• Adhesive capacity, Asymptomatic uropathogenic Escherichia coli, FimBE recombinases, Symptomatic uropathogenic Escherichia coli, Type 1 fimbriae-regulating factors, Type 1 fimbrial phase variation,
• MeSH
• adheziny Escherichia coli genetika   metabolismus   MeSH
• bakteriální adheze * MeSH
• bakteriální fimbrie * genetika   metabolismus   MeSH
• bakteriurie mikrobiologie   MeSH
• buněčné linie MeSH
• epitelové buňky * mikrobiologie   MeSH
• infekce vyvolané Escherichia coli * mikrobiologie   MeSH
• lidé MeSH
• mannosa metabolismus   farmakologie   MeSH
• mnohočetná bakteriální léková rezistence * genetika   MeSH
• proteiny fimbrií * genetika   metabolismus   MeSH
• proteiny z Escherichia coli genetika   metabolismus   MeSH
• regulace genové exprese u bakterií MeSH
• uropatogenní Escherichia coli * genetika   účinky léků   izolace a purifikace   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adheziny Escherichia coli MeSH
• mannosa MeSH
• proteiny fimbrií * MeSH
• proteiny z Escherichia coli MeSH

OBJECTIVE: Comparison of antigenic structures of Bordetella pertussis (B. pertussis) strains isolated from 1967 to 2010 in the Czech Republic. MATERIAL AND METHODS: Seventy strains of B. pertussis were referred to the National Reference Laboratory (NRL) for Pertussis and Diphtheria within the surveillance of pertussis from all over the Czech Republic (CR) between 1967 and 2010. To study the strains, the analysis was performed of the genome sequences encoding the surface immunogenic structures--the pertussis toxin S1 subunit gene (ptxA), pertactin gene region 1 (prnA), type 3 fimbriae gene (fim3)--and pertussis toxin promoter (ptxP) responsible for the regulation of the production of pertussis toxin. RESULTS: For the study set of B. pertussis strains, the sequencing analysis revealed changes in all genomic regions studied. The isolates from three periods differ in the allelic profile. In period I (19671978) with the use of whole cell pertussis vaccine (wP), the following two profiles were the most common: ptxP(1), ptxA(2), prnA(1), fim3(1) and ptxP(1), ptxA(1), prnA(3), fim3(1). In period 2 (19902007) with the switch to acellular pertussis vaccine (aP), the most common profile was: ptxP(3), ptxA(1), prnA(2), fim3(2). Period 3 (20082010) with the use of aP was characterized by the predominance of the following two profiles which had never been found in period 1: ptxP(3), ptxA(1), prnA(2), fim3(2) and ptxP(3) ptxA(1), prnA(2), fim3(1). CONCLUSIONS: Sequencing of the genomic regions ptxP, ptxA, prnA, and fim3 of B. pertussis strains isolated in the CR between 1967 and 2010 confirmed changes in the allelic variants of these regions. The incidence of strains carrying the new allelic variants was increasing after 1995 at the expense of those carrying the original variants. The study results can be interpreted as a partial genetic escape of pathogenic strains of B. pertussis beyond the reach of the pertussis vaccines.

• Klíčová slova
• Bordetella pertussis strain - isolate - sequencing - epidemiology - vaccine.,
• MeSH
• antigenní variace * MeSH
• Bordetella pertussis klasifikace   genetika   imunologie   izolace a purifikace   MeSH
• faktory virulence rodu Bordetella genetika   imunologie   MeSH
• genetická variace MeSH
• lidé MeSH
• pertuse epidemiologie   imunologie   mikrobiologie   MeSH
• pertusová vakcína genetika   imunologie   MeSH
• pertusový toxin genetika   imunologie   MeSH
• proteiny vnější bakteriální membrány genetika   imunologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• faktory virulence rodu Bordetella MeSH
• pertactin MeSH Prohlížeč
• pertusová vakcína MeSH
• pertusový toxin MeSH
• pertussis toxin, S1 subunit MeSH Prohlížeč
• proteiny vnější bakteriální membrány MeSH