ABSTRACT
In a previous study, we reported our discovery of Acanthamoeba contamination in domestic tap water; in that study, we determined that some Acanthamoeba strains harbor endosymbiotic bacteria, via our molecular characterization by mitochondrial DNA restriction fragment length polymorphism (Mt DNA RFLP). Five (29.4%) among 17 Acanthamoeba isolates contained endosymbionts in their cytoplasm, as demonstrated via orcein staining. In order to estimate their pathogenicity, we conducted a genetic characterization of the endosymbionts in Acanthamoeba isolated from domestic tap water via 16S rDNA sequencing. The endosymbionts of Acanthamoeba sp. KA/WP3 and KA/WP4 evidenced the highest level of similarity, at 97% of the recently published 16S rDNA sequence of the bacterium, Candidatus Amoebophilus asiaticus. The endosymbionts of Acanthamoeba sp. KA/WP8 and KA/WP12 shared a 97% sequence similarity with each other, and were also highly similar to Candidatus Odyssella thessalonicensis, a member of the alpha-proteobacteria. The endosymbiont of Acanthamoeba sp. KA/WP9 exhibits a high degree of similarity (85-95%) with genus Methylophilus, which is not yet known to harbor any endosymbionts. This is the first report, to the best of our knowledge, to show that Methylophilus spp. can live in the cytoplasm of Acanthamoeba.
Subject(s)
Animals , Acanthamoeba/isolation & purification , Alphaproteobacteria/classification , Bacteroidetes/classification , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Ribosomal/chemistry , Fresh Water/parasitology , Korea , Methylophilus/classification , Microscopy, Electron, Transmission , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , SymbiosisABSTRACT
A large number of putative rhizobial isolates were obtained from the root nodules of various chickpea cultivars growing in agricultural research fields. Of these, thirty were selected and characterized for traits, such as, generation time, intrinsic azide resistance and several symbiotic characters.
Subject(s)
Agriculture , Alphaproteobacteria/classification , Cicer/microbiology , Plant Roots/microbiology , Soil Microbiology , SymbiosisABSTRACT
La Angiomatosis Bacilar (AB) es una rara enfermedad infecciosa que afecta piel y vísceras de pacientes con el virus de inmunodeficiencia adquirida y otros inmunodeprimidos. Se caracteriza por presentar lesiones cutáneas vasculares asintomáticas que pueden diseminarse sistémicamente. El agente causal de la angiomatosis bacilar está estrechamente relacionada con la Rocha-limaea henselae