Magdalena Florek

CTX-M-15-producing Escherichia coli clone B2-O25b-ST131 and Klebsiella spp. isolates in municipal wastewater treatment plant effluents

OBJECTIVES The global occurrence of antibiotic resistance genes in bacteria in water environments is an increasing concern. Treated wastewater was sampled daily over a 45 day period from the outflow of a municipal wastewater treatment plant in Brno, Czech Republic, and examined for extended-spectrum β-lactamase (ESBL)-producing bacteria. METHODS Water samples were cultivated on MacConkey agar with cefotaxime (2 mg/L) and individual colonies were examined for ESBL production. Phenotypic ESBL-positive bacteria identified as Escherichia coli or Klebsiella spp. were tested for the presence of antibiotic resistance genes, the virulence gene afa/dra and the bla(CTX-M) upstream region. Genetic relatedness was analysed by PFGE, multilocus sequence typing and plasmid analysis. RESULTS A total of 68 ESBL-producing Enterobacteriaceae isolates were detected in 34 out of 45 wastewater samples. ESBL-producing isolates included 26 E. coli isolates, 4 Klebsiella pneumoniae isolates and 1 Klebsiella oxytoca isolate. The pandemic and multiresistant B2-O25b-ST131 clone was predominant, being detected among 19 E. coli isolates, and 17 of the B2-O25b-ST131 isolates were positive for the FIA replicon and the afa/dra operon and had an IS26 element flanking bla(CTX-M-15). Seventeen of the B2-O25b-ST131 isolates showed closely related PFGE profiles (defined by 84% band similarity) and belonged to identical clonal groups. CONCLUSIONS The results highlight the inadequacy of the treatment process in removing multiresistant bacteria from municipal wastewater and point to a risk of transmission of clinically important multiresistant strains, such as the pandemic ST131 clone, to the environment. This is the first study demonstrating the pandemic ST131 clone in wastewater.

Copper(I) iodide complexes containing new aliphatic aminophosphine ligands and diimines—luminescent properties and antibacterial activity

The new, water soluble, aminomethylphosphines were synthesized from P(CH2OH)3 and alkylpiperazines: P(CH2N(CH2CH2)2NCH3)3 (1) and P(CH2N(CH2CH2)2NCH2CH3)3 (2). Described already in literature P(CH2N(CH2CH2)2O)3 (3) were also obtained. The spectroscopic 1H, 31P and 13C NMR analyses and crystallographic studies of 1, 2 and 3 demonstrate that all these compounds have similar structures and spectroscopic properties, which almost do not depend on aliphatic rings in the molecules. Heteroleptic copper(I) iodide complexes with phosphines mentioned above and 2,2′-bipyridine (bpy): [CuI(bpy)P(CH2N(CH2CH2)2NCH3)3] (1B), [CuI(bpy)P(CH2N(CH2CH2)2NCH2CH3)3] (2B), [CuI(bpy)P(CH2N(CH2CH2)2O)3] (3B) or 1,10-phenanthroline (phen): [CuI(phen)P(CH2N(CH2CH2)2NCH3)3] (1P), [CuI(phen)P(CH2N(CH2CH2)NCH2CH3)3] (2P), [CuI(phen)P(CH2N(CH2CH2)2O)3] (3P) were also synthesized. All complexes were characterized by 1H, 31P and 13C NMR spectroscopy also. Molecular structures of 1P·PhCH3 and 3P·0.5Cu2I2(phen)2 were determined from single crystal X-ray diffraction studies. Upon excitation at 470 nm, all complexes in the solid state exhibit red photoluminescence due to charge transfer transition. The luminescence of phen complexes is higher than the luminescence of bpy ones. The presented phosphines and copper(I) complexes were screened for their in vitro antibacterial and antifungal activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus strains and Candida albicans. All the copper complexes exhibit significant antibacterial activity against Staphylococcus aureus strains. The activity of 1,10-phenanthroline complexes is higher than 2,2′-bipyridine complexes.

Biological activity and structure dependent properties of cuprous iodide complexes with phenanthrolines and water soluble tris (aminomethyl) phosphanes.

This paper presents the biological activity of copper(I) iodide complexes with 1,10-phenanthroline (phen) or 2,9-dimethyl-1,10-phenanthroline (dmp) and three tris (aminomethyl) phosphanes: P(CH2N(CH2CH2)2NCH3)3 (1), P(CH2N(CH2CH2)2O)3 (2) and P (CH2N(CH3)CH2CH2OH)3 (3). Crystallographic and DFT data indicate a significantly stronger binding ability of 3 in the complexes [CuI (phen) P (CH2N (CH3)CH2CH2OH)3] (3P) and [CuI(dmp)P(CH2N(CH3)CH2CH2OH)3] (3N) in comparison to the 1 or 2 ligands. Most probably, this is caused by the relatively small steric requirements of 3. The complexes with dmp exhibit a very high in vitro activity against the Staphylococcus aureus strain (MIC - minimal inhibitory concentration: 2.5-5 μg/mL) and Candida albicans diploid fungus (MIC: 1.25-2.5 μg/mL). All the tested complexes also show a strong in vitro antitumor activity against human ovarian carcinoma cell lines: MDAH 2774 (IC50: 7-2 μM) and cisplatin-resistant SCOV3 (IC50: 3-2 μM). Interestingly, the complexes with dmp of higher biological activity more weakly interact with bovine serum albumin (BSA) and less efficiently cleave the pBluescriptSK+ plasmid.

Silver(I) 1,3,5-Triaza-7-phosphaadamantane Coordination Polymers Driven by Substituted Glutarate and Malonate Building Blocks: Self-Assembly Synthesis, Structural Features, and Antimicrobial Properties

Three new bioactive silver(I) coordination polymers formulated as [Ag2(μ2-PTA)(μ3-PTA)(μ2-pga)(H2O)]n·6H2O (1), [Ag2(μ2-PTA)(μ3-PTA)(Hpmal)2]n·2H2O (2), and [Ag(μ3-PTA) (Hdmga)]n (3) were self-assembled from Ag2O, 1,3,5-triaza-7-phosphaadamantane (PTA), and a substituted dicarboxylic acid (3-phenylglutaric acid (H2pga), phenylmalonic acid (H2pmal), or 3,3-dimethylglutaric acid (H2dmga)) as an ancillary ligand. Compounds 1-3 were fully characterized by IR and NMR spectroscopy, ESI-MS(±), elemental analysis, and single-crystal X-ray diffraction, revealing that their architectural and topological diversity is governed by structural modulation of a dicarboxylate building block. The structures vary from a 1D cyclic chain with the SP 1-periodic net (4,4)(0,2) topology in 2 to distinct 2D metal-organic layers with the cem-d and hcb topologies in 1 and 3, respectively. In addition, compounds 1-3 exhibit a notable antimicrobial efficiency against a panel of common Gram-negative (E. coli and P. aeruginosa) and Gram-positive (S. aureus) bacteria and yeast (C. albicans). The best normalized minimum inhibitory concentrations (normalized MIC) of 11-23 nmol mL(-1) (for bacterial strains) or 68 nmol mL(-1) (for a yeast strain) are shown by compound 2, and the eventual structure-bioactivity correlations are discussed.

Copper(I) (pseudo)halide complexes with neocuproine and aminomethylphosphines derived from morpholine and thiomorpholine - in vitro cytotoxic and antimicrobial activity and the interactions with DNA and serum albumins.

Herein, a series of CuI or CuNCS complexes with neocuproine (2,9‐dimethyl‐1,10‐phenanthroline: dmp) and two tris(aminomethyl)phosphines derived from morpholine (P(CH2N(CH2CH2)2O)3) or thiomorpholine (P(CH2N(CH2CH2)2S)3) were tested as cytotoxic agents in vitro towards mouse colon carcinoma (CT26) and human lung adenocarcinoma (A549). The studies showed that the complexes exhibit potential antitumor properties, displayed by IC50 values below 10 μm towards the tested cell lines, in the case of 4‐h incubation time with the examined compounds. Moreover, a high antimicrobial activity of all the complexes was observed against Staphylococcus aureus and Candida albicans with minimal inhibitory concentrations equal to 1–2 μg/mL. To gain insight into the molecular mechanism of biological activity of the complexes, we investigated also their interactions with plasmid DNA (pUC18) and the human and bovine serum albumins. Gel electrophoresis experiments demonstrated that all the compounds were comparably efficient in DNA degradation process; however, luminescence quenching showed surprising dependence on the interactions strength of the used compounds with the albumins. Apart from exceptionally effective [CuI(dmp)P(CH2N(CH2CH2)2O)3], the complexes with P(CH2N(CH2CH2)2O)3 quenched more strongly luminescence of bovine serum albumin, while the complexes with P(CH2N(CH2CH2)2S)3 were more active in the quenching of human serum albumin luminescence.

New silver BioMOFs driven by 1,3,5-triaza-7-phosphaadamantane-7-sulfide (PTAS): synthesis, topological analysis and antimicrobial activity

Two new bioactive silver–organic frameworks [Ag(μ3-PTAS)]n(NO3)n·nH2O (1) and [Ag4(μ4-PTAS)(μ5-PTAS)(μ2-SO4)2(H2O)2]n·2nH2O (2) were easily assembled, thus opening up the application of PTAS as a versatile N,S-building block in the crystal engineering of MOFs. The obtained products reveal infinite 3D networks driven by multiply bridging PTAS spacers that adopt unprecedented N2S-coordination modes. The topological analysis of 1 discloses an uninodal 3-connected net with the srs (SrSi2) topology, whereas 2 features a pentanodal 3,4,5-connected net with a hitherto undocumented topology. Apart from representing the first MOFs derived from PTAS, the compounds 1 and 2 display notable antibacterial and antifungal activities.

Polymerase chain reaction–based identification of clinically relevant Pasteurellaceae isolated from cats and dogs in Poland

A set of polymerase chain reaction (PCR) assays for identification of the most important Pasteurellaceae species encountered in cats and dogs were developed. Primers for Pasteurella multocida were designed to detect a fragment of the kmt, a gene encoding the outer-membrane protein. Primers specific to Pasteurella canis, Pasteurella dagmatis, and Pasteurella stomatis were based on the manganese-dependent superoxide dismutase gene (sodA) and those specific to [Haemophilus] haemoglobinophilus on species-specific sequences of the 16S ribosomal RNA gene. All the primers were tested on respective reference and control strains and applied to the identification of 47 canine and feline field isolates of Pasteurellaceae. The PCR assays were shown to be species specific, providing a valuable supplement to phenotypic identification of species within this group of bacteria.

Genetic Diversity of Pasteurella dagmatis as Assessed by Analysis of the 16S rRNA and rpoB Gene Sequences

A total of 16 Pasteurella dagmatis strains, including 11 feline and 4 canine isolates as well as one strain isolated from a tiger, were analyzed using partial 16S rRNA and rpoB gene sequence comparison. Phylogenetic studies based on both genes revealed that the population of P. dagmatis recovered from cats in Poland differs markedly from canine strains, constituting a well-separated cluster within Pasteurella sensu stricto species group. The isolate from a tiger seems to represent yet another evolutionary lineage within P. dagmatis.