Editor: Aharon Oren
Whole genome-based assessment of the taxonomic position of the arthropod pathogenic bacterium Rickettsiella grylli
Article first published online: 17 APR 2008
© 2008 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Letters
Volume 283, Issue 1, pages 117–127, June 2008
How to Cite
Leclerque, A. (2008), Whole genome-based assessment of the taxonomic position of the arthropod pathogenic bacterium Rickettsiella grylli. FEMS Microbiology Letters, 283: 117–127. doi: 10.1111/j.1574-6968.2008.01158.x
- Issue published online: 17 APR 2008
- Article first published online: 17 APR 2008
- Received 2 February 2008; accepted 6 March 2008.First published online 17 April 2008.
- Rickettsiella grylli;
- panorthologous genes;
- Shimodaira–Hasegawa test;
- Kishino–Hasegawa test
Rickettsiella grylli is an intracellular bacterial pathogen of aquatic and terrestrial arthropods. Previous determination of its 16S rRNA-encoding sequence has led to the taxonomic classification of the genus Rickettsiella in the class Gammaproteobacteria, order Legionellales, family Coxiellaceae, i.e. in close vicinity to vertebrate pathogenic bacteria of the genera Coxiella and Legionella. Here we use the additional information available from the recently published first whole genome sequence from this genus to evaluate critically the taxonomic classification of R. grylli beyond the 16S rRNA gene level. Using phylogenetic reconstruction, together with significance testing on a data basis defined by a core set of 211 previously identified families of protein-encoding genes, together with a reanalysis of 16S rRNA gene data, the present study firmly corroborates the assignment of this species to both the class Gammaproteobacteria and the order Legionellales. However, the results obtained from concatenated and single protein, single protein-encoding gene, and 16S rRNA gene data demonstrate a similar phylogenetic distance of R. grylli to both the Coxiellaceae and the Legionellaceae and are, therefore, inconsistent with its current family-level classification. Consequently, a respective reorganization of the order Legionellales is proposed.