Publications

coexistence of wolbachia with buchnera aphidicola and a secondary symbiont in the aphid cinara cedri.	intracellular symbiosis is very common in the insect world. for the aphid cinara cedri, we have identified by electron microscopy three symbiotic bacteria that can be characterized by their different sizes, morphologies, and electrodensities. pcr amplification and sequencing of the 16s ribosomal dna (rdna) genes showed that, in addition to harboring buchnera aphidicola, the primary endosymbiont of aphids, c. cedri harbors a secondary symbiont (s symbiont) that was previously found to be associat ...	2004	15375144
comparative analysis of two genomic regions among four strains of buchnera aphidicola, primary endosymbiont of aphids.	preliminary analysis of two selected genomic regions of buchnera aphidicola bcc, the primary endosymbiont of the cedar aphid cinara cedri, has revealed a number of interesting features when compared with the corresponding homologous regions of the three b. aphidicola genomes previously sequenced, that are associated with different aphid species. both regions exhibit a significant reduction in length and gene number in b. aphidicola bcc, as it could be expected since it possess the smallest bacte ...	2004	15716086
a small microbial genome: the end of a long symbiotic relationship?	intracellular bacteria are characterized by genome reduction. the 422,434-base pair genome of buchnera aphidicola bcc, primary endosymbiont of the aphid cinara cedri, is approximately 200 kilobases smaller than the previously sequenced b. aphidicola genomes. b. aphidicola bcc has lost most metabolic functions, including the ability to synthesize the essential amino acid tryptophan and riboflavin. in addition, most retained genes are evolving rapidly. possibly, b. aphidicola bcc is losing its sym ...	2006	17038625
evolution of the secondary symbiont "candidatus serratia symbiotica" in aphid species of the subfamily lachninae.	buchnera aphidicola bcc, the primary endosymbiont of the aphid cinara cedri (subfamily lachninae), is losing its symbiotic capacity and might be replaced by the coresident "candidatus serratia symbiotica." phylogenetic and morphological analyses within the subfamily lachninae indicate two different "ca. serratia symbiotica" lineages and support the longtime coevolution of both symbionts in c. cedri.	2008	18502932
the striking case of tryptophan provision in the cedar aphid cinara cedri.	buchnera aphidicola bcc has lost its symbiotic role as the tryptophan supplier to the aphid cinara cedri. we report the presence of a plasmid in this endosymbiont that contains the trpeg genes. the remaining genes for the pathway (trpdcba) are located on the chromosome of the secondary endosymbiont "candidatus serratia symbiotica." thus, we propose that a symbiotic consortium is necessary to provide tryptophan.	2008	18586942
selection for translational robustness in buchnera aphidicola, endosymbiotic bacteria of aphids.	its strong intergenerational bottlenecks and effectively asexual reproduction have led buchnera aphidicola, the endocellular symbiotic bacterium of aphids, to spectacular evolutionary and genomic changes in comparison with its free-living bacterial cousins. these changes summarize into high fixation rates of mildly deleterious destabilizing mutations. this predicts a sharp decline of its fitness and the consequent early demise of this endosymbiotic bacterium. its survival for hundreds of million ...	2009	19126868
a genomic reappraisal of symbiotic function in the aphid/buchnera symbiosis: reduced transporter sets and variable membrane organisations.	buchnera aphidicola is an obligate symbiotic bacterium that sustains the physiology of aphids by complementing their exclusive phloem sap diet. in this study, we reappraised the transport function of different buchnera strains, from the aphids acyrthosiphon pisum, schizaphis graminum, baizongia pistaciae and cinara cedri, using the re-annotation of their transmembrane proteins coupled with an exploration of their metabolic networks. although metabolic analyses revealed high interdependencies bet ...	2011	22229056
the genome of buchnera aphidicola from the aphid cinara tujafilina provides new clues about the evolutionary history of metabolic losses in bacterial endosymbionts.	the symbiotic association between aphids (homoptera) and buchnera aphidicola (γ-proteobacteria) started about 100-200 million years ago. as a consequence of this relationship, the bacterial genome has undergone a prominent size reduction. the downsize genome process starts when the bacterium enters the host, and will probably end with its extinction and replacement by another healthier bacterium, or with the establishment of metabolic complementation between two or more bacteria. nowadays, sever ...	2011	21571878
Serratia symbiotica from the aphid Cinara cedri: a missing link from facultative to obligate insect endosymbiont.	The genome sequencing of Buchnera aphidicola BCc from the aphid Cinara cedri, which is the smallest known Buchnera genome, revealed that this bacterium had lost its symbiotic role, as it was not able to synthesize tryptophan and riboflavin. Moreover, the biosynthesis of tryptophan is shared with the endosymbiont Serratia symbiotica SCc, which coexists with B. aphidicola in this aphid. The whole-genome sequencing of S. symbiotica SCc reveals an endosymbiont in a stage of genome reduction that is ...	2011	22102823
comparative genomics of serratia spp.: two paths towards endosymbiotic life.	symbiosis is a widespread phenomenon in nature, in which insects show a great number of these associations. buchnera aphidicola, the obligate endosymbiont of aphids, coexists in some species with another intracellular bacterium, serratia symbiotica. of particular interest is the case of the cedar aphid cinara cedri, where b. aphidicola bcc and s. symbiotica scc need each other to fulfil their symbiotic role with the insect. moreover, various features seem to indicate that s. symbiotica scc is cl ...	2012	23077583
genomic analysis of the regulatory elements and links with intrinsic dna structural properties in the shrunken genome of buchnera.	buchnera aphidicola is an obligate symbiotic bacterium, associated with most of the aphididae, whose genome has drastically shrunk during intracellular evolution. gene regulation in buchnera has been a matter of controversy in recent years as the combination of genomic information with the experimental results has been contradictory, refuting or arguing in favour of a functional and responsive transcription regulation in buchnera.the goal of this study was to describe the gene transcription regu ...	2013	23375088
settling down: the genome of serratia symbiotica from the aphid cinara tujafilina zooms in on the process of accommodation to a cooperative intracellular life.	particularly interesting cases of mutualistic endosymbioses come from the establishment of co-obligate associations of more than one species of endosymbiotic bacteria. throughout symbiotic accommodation from a free-living bacterium, passing through a facultative stage and ending as an obligate intracellular one, the symbiont experiences massive genomic losses and phenotypic adjustments. here, we scrutinized the changes in the coevolution of serratia symbiotica and buchnera aphidicola endosymbion ...	2014	24951564
reinventing the wheel and making it round again: evolutionary convergence in buchnera-serratia symbiotic consortia between the distantly related lachninae aphids tuberolachnus salignus and cinara cedri.	virtually all aphids (aphididae) harbor buchnera aphidicola as an obligate endosymbiont to compensate nutritional deficiencies arising from their phloem diet. many species within the lachninae subfamily seem to be consistently associated also with serratia symbiotica we have previously shown that both cinara (cinara) cedri and cinara (cupressobium) tujafilina (lachninae: eulachnini tribe) have indeed established co-obligate associations with both buchnera and s. symbiotica however, while buchner ...	2016	27190007
metabolic complementation in bacterial communities: necessary conditions and optimality.	bacterial communities may display metabolic complementation, in which different members of the association partially contribute to the same biosynthetic pathway. in this way, the end product of the pathway is synthesized by the community as a whole. however, the emergence and the benefits of such complementation are poorly understood. herein, we present a simple model to analyze the metabolic interactions among bacteria, including the host in the case of endosymbiotic bacteria. the model conside ...	2016	27774085
determinism and contingency shape metabolic complementation in an endosymbiotic consortium.	bacterial endosymbionts and their insect hosts establish an intimate metabolic relationship. bacteria offer a variety of essential nutrients to their hosts, whereas insect cells provide the necessary sources of matter and energy to their tiny metabolic allies. these nutritional complementations sustain themselves on a diversity of metabolite exchanges between the cell host and the reduced yet highly specialized bacterial metabolism-which, for instance, overproduces a small set of essential amino ...	2017	29213256