This Article Full Text Full Text (PDF) Supplemental material Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Frutos, R. Articles by Martinez, D. Search for Related Content PubMed PubMed Citation Articles by Frutos, R. Articles by Martinez, D.

 Previous Article  |  Next Article 

Journal of Bacteriology, April 2006, p. 2533-2542, Vol. 188, No. 7
0021-9193/06/$08.00+0     doi:10.1128/JB.188.7.2533-2542.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Comparative Genomic Analysis of Three Strains of Ehrlichia ruminantium Reveals an Active Process of Genome Size Plasticity

Roger Frutos,^1* Alain Viari,² Conchita Ferraz,³ Anne Morgat,^2,4 Sophie Eychenié,³ Yane Kandassamy,¹ Isabelle Chantal,¹ Albert Bensaid,^1, Eric Coissac,² Nathalie Vachiery,¹ Jacques Demaille,³ and Dominique Martinez¹

CIRAD-Emvt, TA30/G, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France,¹ Inria Rhône-Alpes—Projet HELIX, 655 Av. de l'Europe, 38330 Montbonnot-Saint Martin, France,² Centre de Séquençage Génomique, IGH-CNRS-UPR 1142, 141 rue de la Cardonille, 34396 Montpellier Cedex 5, France,³ Swiss Institute of Bioinformatics, Swiss-Prot Group, 1 rue Michel, Servet, CH-1211 Geneva 4, Switzerland⁴

Received 31 August 2005/ Accepted 9 January 2006

Ehrlichia ruminantium is the causative agent of heartwater, a major tick-borne disease of livestock in Africa that has been introduced in the Caribbean and is threatening to emerge and spread on the American mainland. We sequenced the complete genomes of two strains of E. ruminantium of differing phenotypes, strains Gardel (Erga; 1,499,920 bp), from the island of Guadeloupe, and Welgevonden (Erwe; 1,512,977 bp), originating in South Africa and maintained in Guadeloupe in a different cell environment. Comparative genomic analysis of these two strains was performed with the recently published parent strain of Erwe (Erwo) and other Rickettsiales (Anaplasma, Wolbachia, and Rickettsia spp.). Gene order is highly conserved between the E. ruminantium strains and with A. marginale. In contrast, there is very little conservation of gene order with members of the Rickettsiaceae. However, gene order may be locally conserved, as illustrated by the tuf operons. Eighteen truncated protein-encoding sequences (CDSs) differentiate Erga from Erwe/Erwo, whereas four other truncated CDSs differentiate Erwe from Erwo. Moreover, E. ruminantium displays the lowest coding ratio observed among bacteria due to unusually long intergenic regions. This is related to an active process of genome expansion/contraction targeted at tandem repeats in noncoding regions and based on the addition or removal of ca. 150-bp tandem units. This process seems to be specific to E. ruminantium and is not observed in the other Rickettsiales.

Supplemental material for this article may be found at http://jb.asm.org/.

Present address: Centre de Recerca en Sanitat Animal, Campus de Bellaterra, Edifici V, 08193 Bellaterra, Barcelona, Spain.

This article has been cited by other articles:

• Cho, N.-H., Kim, H.-R., Lee, J.-H., Kim, S.-Y., Kim, J., Cha, S., Kim, S.-Y., Darby, A. C., Fuxelius, H.-H., Yin, J., Kim, J. H., Kim, J., Lee, S. J., Koh, Y.-S., Jang, W.-J., Park, K.-H., Andersson, S. G. E., Choi, M.-S., Kim, I.-S. (2007). The Orientia tsutsugamushi genome reveals massive proliferation of conjugative type IV secretion system and host cell interaction genes. Proc. Natl. Acad. Sci. USA 104: 7981-7986 [Abstract] [Full Text]  
• McBride, J. W., Doyle, C. K., Zhang, X., Cardenas, A. M., Popov, V. L., Nethery, K. A., Woods, M. E. (2007). Identification of a Glycosylated Ehrlichia canis 19-Kilodalton Major Immunoreactive Protein with a Species-Specific Serine-Rich Glycopeptide Epitope. Infect. Immun. 75: 74-82 [Abstract] [Full Text]