Obligate bacterial endosymbionts of Acanthamoeba spp. related to the ß-Proteobacteria: Proposal of 'Candidatus Procabacter acanthamoebae' gen. nov., sp. nov.
- Author(s)
- Matthias Horn, Thomas R. Fritsche, Tanja Linner, R K Gautom, Marit Harzenetter, Michael Wagner
- Abstract
All obligate bacterial endosymbionts of free-living amoebae currently described are affiliated with the a-Proteobacteria, the Chlamydiales or the phylum Cytophaga-Havobacterium-Bacteroides. Here, six rod-shaped Gram-negative obligate bacterial endosymbionts of clinical and environmental isolates of Acanthamoeba spp. from the USA and Malaysia are reported. Comparative 16S rDNA sequence analysis demonstrated that these endosymbionts form a novel, monophyletic lineage within the ß-Proteobacteria, showing less than 90% sequence similarity to all other recognized members of this subclass. 23S rDNA sequence analysis of two symbionts confirmed this affiliation and revealed the presence of uncommon putative intervening sequences of 146 bp within helix-25 that shared no sequence homology to any other bacterial rDNA. In addition, the 23S rRNA of these endosymbionts displayed one polymorphism at the target site of oligonucleotide probe BET42a that is conserved in all other sequenced ß-Proteobacteria. Intra-cytoplasmatic localization of the endosymbionts within the amoebal host cells was confirmed by electron microscopy and fluorescence in situ hybridization with a specific 16S rRNA-targeted oligonucleotide probe. Based on these findings, the provisional name 'Candidatus Procabacter acanthamoebae' is proposed for classification of a representative of the six endosymbionts of Acanthamoeba spp. studied in this report. Comparative 18S rDNA sequence analysis of the Acanthamoeba host cells revealed their membership with either Acanthamoeba 18S rDNA sequence type T5 (Acanthamoeba lenticulata) or sequence type T4, which comprises the majority of All Acanthamoeba isolates.
- Organisation(s)
- External organisation(s)
- Jones Group, vermicon AG, Technische Universität München
- Journal
- International Journal of Systematic and Evolutionary Microbiology
- Volume
- 52
- Pages
- 599-605
- No. of pages
- 7
- ISSN
- 1466-5026
- Publication date
- 2002
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 1060 Biology
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/d3f0b649-ab84-49b7-b372-e0cdb3f3666a