Genotypic characterization, based on the analysis of restriction fragment length polymorphism of the recA gene fragment PCR product (recA PCR-RFLP), was performed on members of the former Erwinia genus. PCR primers deduced from published recA gene sequences of Erwinia carotovora allowed the amplification of an approximately 730 bp DNA fragment from each of the 19 Erwinia species tested. Amplified recA fragments were compared using RFLP analysis with four endonucleases (AluI, HinfI, TasI and Tru1I), allowing the detection of characteristic patterns of RFLP products for most of the Erwinia species. Between one and three specific RFLP groups were identified among most of the species tested (Erwinia amylovora, Erwinia ananas, Erwinia cacticida, Erwinia cypripedii, Erwinia herbicola, Erwinia mallotivora, Erwinia milletiae, Erwinia nigrifluens, Erwinia persicina, Erwinia psidii, Erwinia quercina, Erwinia rhapontici, Erwinia rubrifaciens, Erwinia salicis, Erwinia stewartii, Erwinia tracheiphila, Erwinia uredovora, Erwinia carotovora subsp. atroseptica, Erwinia carotovora subsp. betavasculorum, Erwinia carotovora subsp. odorifera and Erwinia carotovora subsp. wasabiae). However, in two cases, Erwinia chrysanthemi and Erwinia carotovora subsp. carotovora, 15 and 18 specific RFLP groups were detected, respectively. The variability of genetic patterns within these bacteria could be explained in terms of their geographic origin and/or wide host-range. The results indicated that PCR-RFLP analysis of the recA gene fragment is a useful tool for identification of species and subspecies belonging to the former Erwinia genus, as well as for differentiation of strains within E. carotovora subsp. carotovora and E. chrysanthemi.

The cyanobacterial genus Arthrospira appears very conserved and has been divided into five main genetic clusters on the basis of molecular taxonomy markers. Genetic studies of seven Arthrospira strains, including genome sequencing, have enabled a better understanding of those photosynthetic prokaryotes. Even though genetic manipulations have not yet been performed with success, many genomic and proteomic features such as stress adaptation, nitrogen fixation, or biofuel production have been characterized. Many of above-mentioned studies aimed to optimize the cultivation conditions. Factors like the light intensity and quality, the nitrogen source, or different modes of growth (auto-, hetero-, or mixotrophic) have been studied in detail. The scaling-up of the biomass production using photobioreactors, either closed or open, was also investigated to increase the production of useful compounds. The richness of nutrients contained in the genus Arthrospira can be used for promising applications in the biomedical domain. Ingredients such as the calcium spirulan, immulina, C-phycocyanin, and γ-linolenic acid (GLA) show a strong biological activity. Recently, its use in the fight against cancer cells was documented in many publications. The health-promoting action of “Spirulina” has been demonstrated in the case of cardiovascular diseases and age-related conditions. Some compounds also have potent immunomodulatory properties, promoting the growth of beneficial gut microflora, acting as antimicrobial and antiviral. Products derived from Arthrospira were shown to successfully replace biomaterial scaffolds in regenerative medicine. Supplementation with the cyanobacterium also improves the health of livestock and quality of the products of animal origin. They were also used in cosmetic preparations.

Pectobacterium strains isolated from potato stems in Finland, Poland and the Netherlands were subjected to polyphasic analyses to characterize their genomic and phenotypic features. Phylogenetic analysis based on 382 core proteins showed that the isolates clustered closest to Pectobacterium polaris but could be divided into two clades. Average nucleotide identity (ANI) analysis revealed that the isolates in one of the clades included the P. polaris type strain, whereas the second clade was at the border of the species P. polaris with a 96 % ANI value. In silico genome-to-genome comparisons between the isolates revealed values below 70%, patristic distances based on 1294 core proteins were at the level observed between closely related Pectobacterium species, and the two groups of bacteria differed in genome size, G+C content and results of amplified fragment length polymorphism and Biolog analyses. Comparisons between the genomes revealed that the isolates of the atypical group contained SPI-1-type Type III secretion island and genes coding for proteins known for toxic effects on nematodes or insects, and lacked many genes coding for previously characterized virulence determinants affecting rotting of plant tissue by soft rot bacteria. Furthermore, the atypical isolates could be differentiated from P. polaris by their low virulence, production of antibacterial metabolites and a citrate-negative phenotype. Based on the results of a polyphasic approach including genome-to-genome comparisons, biochemical and virulence assays, presented in this report, we propose delineation of the atypical isolates as a novel species Pectobacterium parvum, for which the isolate s0421^T (CFBP 8630^T=LMG 30828^T) is suggested as a type strain.

The observed onset of climate change at high northern latitudes has highlighted the need to establish current baseline conditions in the Arctic Ocean

Although many antifungal agents are available in clinical treatment, increasing resistance of fungi, especially Candida species, to the available drugs requires the development of new safe and non-toxic compounds with novel modes of action as effective treatment against resistant microorganisms. Cobalt complexes are very interesting and attractive as potential candidates with antimicrobial activity. Their therapeutic uses as antiviral, antibacterial antifungal, antiparasitic, antitumour, transferrin transporters, and anti-inflammatory agents are being intensively investigated. In this study we examined the antifungal activity of Co(III) complexes with diamine chelate ligands against a broad spectrum of Candida species. Minimum inhibitory concentration was determined by the microbroth dilution method and with serial passaging assay; the synergistic antimicrobial activity of the tested complexes combined with two antifungal drugs (ketoconazole and amphotericin B) was made by checkerboard assay. The effects of Co(III) complexes on yeast cell morphology were studied by optical and transmission electron microscopy. The mode of action of Co(III) complexes on the yeast cell wall (sorbitol assay) and cell membrane (ergosterol assay) were investigated. The cytotoxic effects of the tested compounds on red blood cells and the human keratinocyte (HaCaT) cell line were also evaluated. The analyzed compounds revealed significant antifungal activity for selected strains of Candida species; [CoCl₂(dap)₂]Cl (1) and [CoCl₂(en)₂]Cl (2) were more effective than ketoconazole. Its probable mechanism of action did not involve the cell wall or ergosterol binding. However, the checkerboard assay showed, that the antifungal activity of ketoconazole increased in combination with the tested complexes of Co(III). Our results suggest that both diamine complexes with Co(III) analogs caused damage to mitochondrial membrane or the membrane of the endoplasmic reticulum. The effect was observed by transmission electron microscope. Co(III) complexes with diamine chelate ligands are non-toxic at concentrations active against Candida species. This study provides new data on potential antifungal drugs, especially against Candida species.