Using DNA hybridization, at least three distinct groups of low molecular mass plasmids were identified in Salmonella enterica subsp. enterica serovar Enteritidis. After sequencing representative plasmids from each group, we concluded that they belonged to ColE1, ColE2, and rolling-circle-like replicating plasmids. Plasmid pK (4245 bp) is a representative of widely distributed ColE1 plasmids. Plasmid pP (4301 bp) is homologous to ColE2 plasmids and was present predominantly in single-stranded DNA form. The smallest plasmids pJ (2096 bp) and pB (1983 bp) were classified as rolling-circle-like replicating plasmids. Both encoded only a single protein essential for their own replication, and they must have existed in an unusual molecular structure, as (i) they were capable of hybridization without denaturation, (ii) their DNA could be linearized with S1 nuclease, and (iii) even after such treatment, the ability to hybridize without denaturation did not disappear.

• MeSH
• bakteriocinové plazmidy MeSH
• denaturace nukleových kyselin MeSH
• DNA bakterií analýza   chemie   genetika   izolace a purifikace   MeSH
• endonukleasy specifické pro jednořetězcové nukleové kyseliny metabolismus   MeSH
• extrachromozomální dědičnost MeSH
• hybridizace nukleových kyselin MeSH
• jednovláknová DNA MeSH
• plazmidy * MeSH
• replikace DNA MeSH
• Salmonella enteritidis genetika   MeSH
• sekvenční analýza DNA MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA bakterií MeSH
• endonukleasy specifické pro jednořetězcové nukleové kyseliny MeSH
• jednovláknová DNA MeSH

ST252 Enterobacter cloacae, producing GES-5 carbapenemase, was isolated in a Czech hospital. blaGES-5 was part of a novel class 1 integron, In1406, which also included a new allele of the aadA15 gene cassette. In1406 was located on a ColE2-like plasmid, pEcl-35771cz (6953bp).

• Klíčová slova
• Class 1 integron, Class A β-lactamase, ColE2-like, Enterobacteriaceae, In1406,
• MeSH
• bakteriální proteiny genetika   MeSH
• beta-laktamasy genetika   MeSH
• Enterobacter cloacae enzymologie   genetika   MeSH
• enterobakteriální infekce mikrobiologie   MeSH
• integrony genetika   MeSH
• lidé MeSH
• multilokusová sekvenční typizace MeSH
• nemocnice MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• bakteriální proteiny MeSH
• beta-laktamasy MeSH
• carbapenemase MeSH Prohlížeč

The aim of this study was to characterize the first cases and outbreaks of OXA-48-like-producing Enterobacteriaceae recovered from hospital settings in the Czech Republic. From 2013 to 2015, 22 Klebsiella pneumoniae isolates, 3 Escherichia coli isolates, and 1 Enterobacter cloacae isolate producing OXA-48-like carbapenemases were isolated from 20 patients. Four of the patients were colonized or infected by two or three different OXA-48-like producers. The K. pneumoniae isolates were classified into nine sequence types (STs), with ST101 being predominant (n = 8). The E. coli isolates were of different STs, while the E. cloacae isolate belonged to ST109. Twenty-four isolates carried blaOXA-48, while two isolates carried blaOXA-181 or blaOXA-232 Almost all isolates (n = 22) carried blaOXA-48-positive plasmids of a similar size (∼60 kb), except the two isolates producing OXA-181 or OXA-232. In an ST45 K. pneumoniae isolate and an ST38 E. coli isolate, S1 nuclease profiling plus hybridization indicated a chromosomal location of blaOXA-48 Sequencing showed that the majority of blaOXA-48-carrying plasmids exhibited high degrees of identity with the pOXA-48-like plasmid pE71T. Additionally, two novel pE71T derivatives, pOXA-48_30715 and pOXA-48_30891, were observed. The blaOXA-181-carrying plasmid was identical to the IncX3 plasmid pOXA181_EC14828, while the blaOXA-232-carrying plasmid was a ColE2-type plasmid, being a novel derivative of pOXA-232. Finally, sequencing data showed that the ST45 K. pneumoniae and ST38 E. coli isolates harbored the IS1R-based composite transposon Tn6237 containing blaOXA-48 integrated into their chromosomes. These findings underlined that the horizontal transfer of pOXA-48-like plasmids has played a major role in the dissemination of blaOXA-48 in the Czech Republic. In combination with the difficulties with their detection, OXA-48 producers constitute an important public threat.

• Klíčová slova
• ColE2-like, IncL, IncX3, Klebsiella pneumoniae, OXA-181, OXA-232, Tn1999.2, Tn1999.5,
• MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální chromozomy genetika   MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• beta-laktamasy genetika   metabolismus   MeSH
• Enterobacteriaceae účinky léků   enzymologie   genetika   MeSH
• Escherichia coli účinky léků   enzymologie   genetika   MeSH
• Klebsiella pneumoniae účinky léků   enzymologie   genetika   MeSH
• mikrobiální testy citlivosti MeSH
• plazmidy genetika   MeSH
• přenos genů horizontální genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• antibakteriální látky MeSH
• bakteriální proteiny MeSH
• beta-laktamasy MeSH
• carbapenemase MeSH Prohlížeč