Does Salmonella diarizonae 58:r:z53 Isolated from a Mallard Duck Pose a Threat to Human Health?

Salmonella diarizonae (IIIb) is frequently isolated from reptiles and less frequently from birds and mammals. However, its isolation from invasive human infections has not been widely reported. Migratory mallard ducks are excellent bioindicators of pathogen presence and pathogen antibiotic resistance (AMR). We present the first isolation from a mallard duck in central Europe of the antibiotic-resistant Salmonella enterica subsp. diarizonae with the unique antigenic pattern 58:r:z53 and report its whole-genome sequencing, serosequencing, and genotyping, which enabled the prediction of its pathogenicity and comparison with phenotypic AMR. The isolated strain was highly similar to S. diarizonae isolated from humans and food. Twenty-four AMR genes were detected, including those encoding aminoglycoside, fluoroquinolone, macrolide, carbapenem, tetracycline, cephalosporin, nitroimidazole, peptide antibiotic, and disinfecting agent/antiseptic resistance. Six Salmonella pathogenicity islands were found (SPI-1, SPI-2, SPI-3, SPI-5, SPI-9, and SPI-13). An iron transport system was detected in SPI-1 centisome C63PI. Plasmid profile analyses showed three to be present. Sequence mutations in the invA and invF genes were noted, which truncated and elongated the proteins, respectively. The strain also harbored genes encoding type-III secretion-system effector proteins and many virulence factors found in S. diarizonae associated with human infections. This study aims to elucidate the AMR and virulence genes in S. enterica subsp. diarizonae that may most seriously threaten human health.

Wild Duck (Anas platyrhynchos) as a Source of Antibiotic-Resistant Salmonella enterica subsp. diarizonae O58-The First Report in Poland.

The "One Health" approach increasingly demonstrates the global spread of pathogenic microorganisms and their antimicrobial resistance in the environment, both in animals and humans. Salmonella enterica subsp. diarizonae is nowadays very often isolated from cold-blooded reptiles to a lesser extent from sheep, but unfortunately more and more often from humans. However, there are a few studies describing the isolation of Salmonella enterica subsp. diarizonae from migratory wild birds. The mallard duck (Anas platyrhynchos), a wild animal that traverses the continent of Eurasia, can be an excellent indicator of the spread of intestinal microbes as well as their resistance to antibiotics. This is the first report of the Salmonella enterica subsp. diarizonae detection in Poland in a migrating mallard duck. This research presented the identification difficulties associated with the isolation of Salmonella enterica subsp. diarizonae using three different biochemical tests and advanced serology tests. At the same time, we detected very high antimicrobial resistance in the isolated strain. By using the minimum inhibitory concentration (MIC) method, it was found that the isolated strain of S. enterica subsp. diarizonae has high antibiotic resistance against 14 of the 33 tested antimicrobials agents. The resistance genes that have been identified in S. enterica subsp. diarizonae include aadA, strA/strB, and blaTEM.

Plasmid- and chromosomal genes-encoded two separate O-polysaccharide chains of Salmonella Uccle (O:3,54)--structural elucidation.

The bacterium Salmonella Uccle belongs to serotype O:54 in the Kauffmann'a-White scheme. Group O:54 is unique among the serogroups belonging to the genus Salmonella. Normally, the enzymes involved in the biosynthesis of the repeating units of somatic antigen are encoded by a set of genes, located in the region of the bacterial chromosome. Expression of O54 factor is associated with the presence of the plasmid. Factor O54 can be lost spontaneously in the subcultures of some serotypes. In these cases, the O54 negative variants become indistinguishable from the serotypes classified in other groups. We noticed lower activity of LPS-u O:3,54 with rabbit sera against antigens O:3, when compared with the activity of sera anti-A:54, which may indicate a partial inhibition of the expression of factor O:3 on the surface of the bacterial cell. The main aim of our study was to answer the question whether the products of different biosynthetic pathways combine on the outer side of the cytoplasmic membrane, thus forming a single chain or separate chains. Therefore, the O-polysaccharides (O-antigen) of Salmonella Uccle O:3,54 were isolated by mild acid degradation of both obtained LPSs and their structure was established using sugar and methylation analysis and NMR spectroscopy. The primary structure of two separate O-polysaccharide chains isolated from Salmonella Uccle were established.

[Phage types recognized within Salmonella Enteritidis strains isolated in Poland in 1996-2007]. / Typy bakteriofagowe rozpoznane wsród szczepów Salmonella Enteritidis wyizolowanych w Polsce w latach 1996-2007.

UNLABELLED: Phage typing carried out according to the well-defined schemes is still recommended as a standard, fast and inexpensive method for epidemiological investigations all over the world to control Salmonella infections. However, the method should be in the hands of well-trained staff. This means that it is generally limited to reference laboratories. AIM: The aim of this study was to perform an analysis of Salmonella Enteritidis phage types occurring in Poland in 1996-2007 basing on the strains received by the National Salmonella Centre for phage typing. MATERIAL AND METHODS: The phage typing (according to the Lalko et al. scheme) carried out in this research work was associated with 750 Salmonella Enteritidis strains isolated in Poland from human and non-human sources, in the dying out period of over 25 years lasting second epidemic caused by this serovar. RESULTS: Types 1, 6 and 7 were the most often identified phage types. They were dominant among human as well as non-human (food, feeds, animals, environment and others) isolates. The great majority of them were of type 7. Type 1 Salmonella Enteritidis strains were isolated in the same number as type 6 strains. A little higher number of strains which presented phage type 3 was reported in comparison with the previous periods of time. CONCLUSIONS: It is worth to be noted that except the same, permanent phage types continuously existing in the environment (i.e., 1, 3, 6, 7), the new types start to appear. They can suggest an appearance of new sources of Salmonella Enteritidis infections, unknown in our country yet, which is very possible as a result of effective elimination of currently existing ones. The obtained results constitute the continuation of the previously done studies and provide the essential and unique data which allow to estimate the more completely epidemiological situation associated with occurrence of this pathogen in Poland.

Influence of diamino acid derivatives of protoporphyrin IX on mouse immunological system: preliminary results.

Immunological response related to photodynamic therapy (PDT) is one of the basic elements that influence on the efficiency of this cancer treatment method. Diamino acid derivatives of protoporphyrin IX are promising photosensitizing agents that are intended to be the components of new anti-tumor drug. The influence of three derivatives - PP(Ser)(2)Arg(2), PP(Ala)(2)Arg(2), PP(Phe)(2)Arg(2) and a mixture of these compounds called Sensyphyrine on mouse immunological system was investigated where animals were exposed and unexposed to the laser irradiation. Porphyrins solutions were injected intravenously, mice were irradiated with the red diode laser at lambda=632 nm. Cells and blood samples were taken at time intervals after irradiation. The levels of interleukin-6, interleukin-1beta and the production of reactive forms of nitrogen by macrophages were determined. The results show that all of the diamino acid derivatives of protoporphyrin IX indicate an immunological response when the light is applied. Each of the porphyrin revealed different impact on mice immunological system. The most potent stimulant properties disclosed PP(Phe)(2)Arg(2) derivative for which the highest values of IL-1beta, IL-6 and NO(2)(-) were noticed. The weakest immunological activation revealed PP(Ser)(2)Arg(2) derivative.