Article

Moya A, Pereto J, Gil R, Latorre A.. Learning how to live together: genomic insights into prokaryote-animal symbioses. Nat Rev Genet 9: 218-229

Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Apartado de correos 22085. 46071 València and CIBER de Epidemiología y Salud Pública, Spain.
Nature Reviews Genetics (Impact Factor: 39.79). 04/2008; 9(3):218-29. DOI: 10.1038/nrg2319
Source: PubMed

ABSTRACT Our understanding of prokaryote-eukaryote symbioses as a source of evolutionary innovation has been rapidly increased by the advent of genomics, which has made possible the biological study of uncultivable endosymbionts. Genomics is allowing the dissection of the evolutionary process that starts with host invasion then progresses from facultative to obligate symbiosis and ends with replacement by, or coexistence with, new symbionts. Moreover, genomics has provided important clues on the mechanisms driving the genome-reduction process, the functions that are retained by the endosymbionts, the role of the host, and the factors that might determine whether the association will become parasitic or mutualistic.

Download full-text

Full-text

Available from: Juli Pereto, Aug 15, 2015
0 Followers
 · 
125 Views
    • "Dependency of Westeberhardia on host - provided metabolites With a genome size reduction to 533 kb and a GC content of 23 . 41% , the Westeberhardia genome exhibits features of degenerative genome evolution following the transition to obligate symbiosis ( Moya et al . , 2008 ) . In addition to reduced effective population sizes in host - associated bacteria com - pared with free - living relatives , small effective population size of C . obscurior ( Schrader et al . , 2014 ) and social insects in general ( Romiguier et al . , 2014 ) could lead to even faster genome degeneration . With a coding density of 70"
    [Show abstract] [Hide abstract]
    ABSTRACT: The evolution of eukaryotic organisms is often strongly influenced by microbial symbionts that confer novel traits to their hosts. Here we describe the intracellular Enterobacteriaceae symbiont of the invasive ant Cardiocondyla obscurior, 'Candidatus Westeberhardia cardiocondylae'. Upon metamorphosis, Westeberhardia is found in gut-associated bacteriomes that deteriorate following eclosion. Only queens maintain Westeberhardia in the ovarian nurse cells from where the symbionts are transmitted to late-stage oocytes during nurse cell depletion. Functional analyses of the streamlined genome of Westeberhardia (533 kb, 23.41% GC content) indicate that neither vitamins nor essential amino acids are provided for the host. However, the genome encodes for an almost complete shikimate pathway leading to 4-hydroxyphenylpyruvate, which could be converted into tyrosine by the host. Taken together with increasing titers of Westeberhardia during pupal stage, this suggests a contribution of Westeberhardia to cuticle formation. Despite a widespread occurrence of Westeberhardia across host populations, one ant lineage was found to be naturally symbiont-free, pointing to the loss of an otherwise prevalent endosymbiont. This study yields insights into a novel intracellular mutualist that could play a role in the invasive success of C. obscurior.The ISME Journal advance online publication, 14 July 2015; doi:10.1038/ismej.2015.119.
    The ISME Journal 07/2015; DOI:10.1038/ismej.2015.119 · 9.27 Impact Factor
  • Source
    • "Mutualistic symbioses between bacteria and animals are widespread, occur in almost all animal phyla and play major roles in the development, health and evolution of their hosts (McFall-Ngai, 2002; Walker and Crossman, 2007; Moya et al., 2008; Fraune and Bosch, 2010; McFall-Ngai et al., 2013). In many mutualistic symbioses, the function of the bacterial symbionts is to provide essential nutrients to their hosts (Moran, 2007; Moya et al., 2008). In chemosynthetic symbioses, the bacteria provide all or most of their host's nutrition using inorganic compounds such as sulfide or hydrogen (H 2) as energy sources to fix carbon dioxide (CO2) into biomass (Stewart et al., 2005; DeChaine and Cavanaugh, 2006; Dubilier et al., 2008; Petersen et al., 2011; Kleiner et al., 2012a). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The gutless marine worm Olavius algarvensis lives in symbiosis with chemosynthetic bacteria that provide nutrition by fixing CO2 into biomass using reduced sulfur compounds as energy sources. A recent metaproteomic analysis of the O. algarvensis symbiosis indicated that carbon monoxide (CO) and hydrogen (H2 ) might also be used as energy sources. We provide direct evidence that the O. algarvensis symbiosis consumes CO and H2 . Single cell imaging using nanoSIMS revealed that one of the symbionts, the γ3-symbiont, uses the energy from CO oxidation to fix CO2 . Pore water analysis revealed considerable in-situ-concentrations of CO and H2 in the O. algarvensis environment, Mediterranean seagrass sediments. Pore water H2 concentrations (89 - 2147 nM) were up to two orders of magnitude higher than in seawater, and up to 36-fold higher than previously known from shallow-water marine sediments. Pore water CO concentrations (17 - 51 nM) were twice as high as in the overlying seawater (no literature data from other shallow-water sediments are available for comparison). Ex-situ incubation experiments showed that dead seagrass rhizomes produced large amounts of CO. CO production from decaying plant material could thus be a significant energy source for microbial primary production in seagrass sediments. This article is protected by copyright. All rights reserved.
    Environmental Microbiology 05/2015; DOI:10.1111/1462-2920.12912 · 6.24 Impact Factor
  • Source
    • "Endosymbiosis is an important evolutionary process in insects, as more than 20% of the insect species depend on endosymbiotic bacteria for their development and survival (Moya et al. 2008; Moran et al. 2008). Insect endosymbioses can be classified based on the host dependency on the bacterium: obligate symbionts are referred to as primary symbionts (P-symbionts), whereas facultative symbionts are called secondary symbionts (S-symbionts). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Bacterial endosymbiosis is an important evolutionary process in insects, which can harbor both obligate and facultative symbionts. The evolution of these symbionts is driven by evolutionary convergence, and they exhibit among the tiniest genomes in prokaryotes. The large host spectrum of facultative symbionts and the high diversity of strategies they use to infect new hosts probably impacts the evolution of their genome and explains why they undergo less severe genomic erosion than obligate symbionts. Candidatus Hamiltonella defensa is suitable for the investigation of the genomic evolution of facultative symbionts because the bacteria are engaged in specific relationships in two clades of insects. In aphids, H. defensa is found in several species with an intermediate prevalence and confers protection against parasitoids. In whiteflies, H. defensa is almost fixed in some species of Bemisia tabaci, which suggests an important role of and a transition towards obligate symbiosis. In the present study, comparisons of the genome of H. defensa present in two B. tabaci species (MEAM1 and MED) and in the aphid Acyrthosiphon pisum revealed that they belong to two distinct clades and underwent specific gene losses. In aphids, it contains highly virulent factors that could allow protection and horizontal transfers. In whiteflies, the genome lost these factors and seems to have a limited ability to acquire genes. However it contains genes that could be involved in the production of essential nutrients, which is consistent with a primordial role for this symbiont. In conclusion, while both lineages of H. defensa have mutualistic interactions with their hosts, their genomes follow distinct evolutionary trajectories that reflect their phenotype and could have important consequences on their evolvability. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
    Genome Biology and Evolution 02/2015; 7(3). DOI:10.1093/gbe/evv030 · 4.53 Impact Factor
Show more