Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1999-2-16
pubmed:databankReference
pubmed:abstractText
Acanthamoebae are ubiquitous soil and water bactivores which may serve as amplification vehicles for a variety of pathogenic facultative bacteria and as hosts to other, presently uncultured bacterial endosymbionts. The spectrum of uncultured endosymbionts includes gram-negative rods and gram-variable cocci, the latter recently shown to be members of the Chlamydiales. We report here the isolation from corneal scrapings of two Acanthamoeba strains that harbor gram-negative rod endosymbionts that could not be cultured by standard techniques. These bacteria were phylogenetically characterized following amplification and sequencing of the near-full-length 16S rRNA gene. We used two fluorescently labelled oligonucleotide probes targeting signature regions within the retrieved sequences to detect these organisms in situ. Phylogenetic analyses demonstrated that they displayed 99.6% sequence similarity and formed an independent and well-separated lineage within the Rickettsiales branch of the alpha subdivision of the Proteobacteria. Nearest relatives included members of the genus Rickettsia, with sequence similarities of approximately 85 to 86%, suggesting that these symbionts are representatives of a new genus and, perhaps, family. Distance matrix, parsimony, and maximum-likelihood tree-generating methods all consistently supported deep branching of the 16S rDNA sequences within the Rickettsiales. The oligonucleotide probes displayed at least three mismatches to all other available 16S rDNA sequences, and they both readily permitted the unambiguous detection of rod-shaped bacteria within intact acanthamoebae by confocal laser-scanning microscopy. Considering the long-standing relationship of most Rickettsiales with arthropods, the finding of a related lineage of endosymbionts in protozoan hosts was unexpected and may have implications for the preadaptation and/or recruitment of rickettsia-like bacteria to metazoan hosts.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-1588578, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-1987160, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-2121990, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-2753854, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-2903176, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-3793451, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-3981353, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-7028991, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-7532718, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-7581321, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-7644549, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-803475, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8081490, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8117465, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8501212, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8594608, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8594610, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8751355, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8829338, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8837410, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8861027, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-8979345, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9004515, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9093261, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9097437, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9103608, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9168621, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9284149, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9435080, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9572937, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9588802, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9603844, http://linkedlifedata.com/resource/pubmed/commentcorrection/9872781-9770279
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0099-2240
pubmed:author
pubmed:issnType
Print
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
206-12
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
In situ detection of novel bacterial endosymbionts of Acanthamoeba spp. phylogenetically related to members of the order Rickettsiales.
pubmed:affiliation
Department of Laboratory Medicine, University of Washington, Seattle, Washington 98195, USA. fritsche@mail.labmed.washington.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't