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Manzano-Marin, A.

Publications and source records attributed to Manzano-Marin, A..

16 recordsLinked to original sources

A multilayered network reveals the centrality of newly discovered Nucleocytoviricota in wastewater treatment plant communities

Viruses of the phylum Nucleocytoviricota are paradigm-shifting entities due to their exceptionally large genomes and complex gene repertoires, which blur the lines between viral and cellular life. Previous research has leveraged computational approaches to map their extensive diversity, while experimental work has started to elucidate the intricate networks they form with hosts, bacterial and other symbionts, co-infecting virophages and other mobile genetic elements. Here, we analyzed deeply sequenced metagenomes sampled from wastewater treatment plants in Denmark, an environment with rapid abiotic changes and known to be a hotbed of dense microbial communities. We discovered 61 novel nucleocytoviruses, 15 virophages and 14 polinton-like viruses. By integrating them with microbial contigs into a multilayered interaction network, we explore the role of these entities on a mesocosm scale. We demonstrate the centrality of nucleocytoviruses, positioning them as important players shaping microbial community structure and evolution in wastewater treatment plants.

microbiology↗

From Eggs to Guts: Symbiotic Association of Sodalis nezarae sp. nov. with the Southern Green Shield Bug Nezara viridula

Phytophagous insects engage in symbiotic relationships with bacteria that contribute to digestion, nutrient supplementation, and development of the host. The analysis of shield bug microbiomes has been mainly focused on the gut intestinal tract predominantly colonized by Pantoea symbionts, and other microbial community members in the gut or other organs have hardly been investigated. In this study, we reveal that the Southern green shield bug Nezara viridula harbours a Sodalis symbiont in several organs, with a notable prevalence in salivary glands, and anterior regions of the midgut. Removing external egg microbiota via sterilization profoundly impacted insect viability but did not disrupt the vertical transmission of Sodalis and Pantoea symbionts. Based on the dominance of Sodalis in testes, we deduce that N. viridula males could be involved in symbiont vertical transmission. Genomic analyses comparing Sodalis species revealed that Sodalis sp. Nvir shares characteristics with both free- living and obligate insect-associated Sodalis spp. Sodalis sp. Nvir also displays genome instability typical of endosymbiont lineages, which suggests ongoing speciation to an obligate endosymbiont. Together, our study reveals that shield bugs harbour unrecognized symbionts that might be paternally transmitted.

microbiology↗

Novel high-quality amoeba genomes reveal widespread codon usage mismatch between giant viruses and their hosts

The need for high-quality protist genomes has prevented in-depth computational and experimental studies of giant virus-host interactions. In addition, our current knowledge of host range is highly biased due to the few hosts used to isolate novel giant viruses. This study presents six high-quality amoeba genomes from known and potential giant virus hosts belonging to two distinct eukaryotic clades: Amoebozoa and Discoba. We employ their genomic data to investigate the predictability of giant virus host range. Using a combination of long and short-read sequencing, we obtained highly contiguous and complete genomes of Acanthamoeba castellanii, Acanthamoeba griffini, Acanthamoeba terricola, Naegleria clarki, Vermamoeba vermiformis, and Willaertia magna, contributing to the collection of sequences for the eukaryotic tree of life. We found that the six amoebae have distinct codon usage patterns and that, contrary to other virus groups, giant viruses often have different and even opposite codon usage with their known hosts. Conversely, giant viruses with matching codon usage are frequently not known to infect or replicate in these hosts. Interestingly, analyses of integrated viral sequences in the amoeba host genomes reveal potential novel virus-host associations. Matching of codon usage preferences is often used to predict virus-host pairs. However, with the broad-scale analyses performed in this study, we demonstrate that codon usage alone appears to be a poor predictor of giant virus host range. We discuss the potential strategies that giant viruses employ to ensure high viral fitness in non-matching hosts. Moreover, this study emphasises the need for more high-quality protist genomes. Finally, the amoeba genomes presented in this study set the stage for future experimental studies to better understand how giant viruses interact with different host species.

evolutionary biology↗

Discordance between phylogenomic datasets in aphids: who is telling the truth?

Aphids (Hemiptera: Aphididae) are intensively studied due to their significance as pests and their captivating biological traits. Despite this considerable research interest, the evolutionary history of this insect family is poorly understood. Recent phylogenomic analyses have produced conflicting topologies, particularly at deep nodes, complicating our understanding of aphid trait evolution. In this work, we aimed to produce new data to unravel the backbone phylogeny of aphids. We sequenced partial and whole mitochondrial genomes from 87 species that were added to 31 published mitochondria. We additionally sequenced 42 nuclear loci across 95 aphid species and sourced 146 genes from 12 new and 61 published genomes from the primary aphid obligate endosymbiont, Buchnera aphidicola. We obtain data from these three sources for a subset of 51 aphid species, facilitating a comparative analysis of their phylogenetic signals. Our analyses confirm the monophyly of subfamilies, validating current taxonomic classifications, except for Eriosomatinae and Calaphidinae. However, relationships between subfamilies remain contentious in both mitochondrial and nuclear phylogenies. The topologies obtained with Buchnera appear fully resolved but exhibit some discordance with host phylogenies at deep evolutionary scales and conflict with views on the evolution of aphid morphology. We discuss alternative hypotheses for these discrepancies. Finally, the paucity of phylogenetic information at deep phylogenetic scales may stem from an initial rapid radiation. Though challenging to establish, this scenario may inherently hinder resolution in aphid phylogenetics.

evolutionary biology↗

A new guest to the blood feast: a novel symbiotic lineage associated with a haematophagous leech from the genus Haementeria

Similarly to other strict blood-feeders, leeches from the Haementeria genus (Hirudinida: Glossiphoniidae) have established a symbiotic association with bacteria harboured intracellularly in oesophageal bacteriomes. Previous genome sequence analyses of these endosymbionts revealed co-divergence with their hosts, a strong genome reduction, and a simplified metabolism largely dedicated to the production of B vitamins, which are nutrients lacking from a blood diet. Candidatus Providencia siddallii has been identified as the obligate nutritional endosymbiont of a monophyletic clade of Mexican and South American Haementeria spp. Nonetheless, given a lack of molecular investigations, the identity of the symbiont housed in the bacteriomes of its sister clade of Central and South American congeners remained unknown. In this work, we report on a novel bacterial endosymbiont found in a representative from this Haementeria clade. We found that this symbiont lineage has evolved from within the Pluralibacter genus, known mainly from clinical, but also environmental strains. Similarly to Ca. Providencia siddallii, the Haementeria-associated Pluralibacter symbiont displays clear signs of genome reduction, accompanied by an A+T-biased sequence composition. Genomic analysis of its metabolic potential revealed a retention of pathways related to B vitamin biosynthesis, supporting its role as a nutritional endosymbiont. Finally, comparative genomics of both Haementeria symbiont lineages suggests that the ancient Providencia symbiont was likely replaced by the novel Pluralibacter one, thus constituting the first reported case of nutritional symbiont replacement in a leech without morphological changes in the bacteriome.

genomics↗

Evolution of an alternative genetic code in the Providencia symbiont of the haematophagous leech Haementeria acuecueyetzin

Strict blood-feeding animals are confronted with a strong B vitamin deficiency. Blood-feeding leeches from the Glossiphoniidae family, similarly to haematophagous insects, have evolved specialised organs called bacteriomes to harbour symbiotic bacteria. Leeches of the Haementeria genus have two pairs of globular bacteriomes attached to the oesophagus which house intracellular Candidatus Providencia siddallii bacteria. Previous work analysing a draft genome of the Providencia symbiont of the Mexican leech Haementeria officinalis showed that, in this species, the bacteria hold a reduced genome capable of synthesising B vitamins. In this work, we aimed to expand our knowledge on the diversity and evolution of Providencia symbionts of Haementeria. For this purpose, we sequenced the symbiont genomes of three selected leech species. We found that all genomes are highly syntenic and have kept a stable genetic repertoire, mirroring ancient insect endosymbionts. Additionally, we found B vitamin pathways to be conserved among these symbionts, pointing to a conserved symbiotic role. Lastly and most notably, we found that the symbiont of Haementeria acuecueyetzin has evolved an alternative genetic code, affecting a portion of its proteome and showing evidence of a lineage-specific and likely intermediate stage of genetic code reassignment.

genomics↗

Co-obligate symbioses have repeatedly evolved across aphids, but partner identity and nutritional contributions vary across lineages

Aphids are a large family of phloem-sap feeders. They typically rely on a single bacterial endosymbiont, Buchnera aphidicola, to supply them with essential nutrients lacking in their diet. This association with Buchnera was described in model aphid species from the Aphidinae subfamily and has been assumed to be representative of most aphids. However, in two lineages, Buchnera has lost some essential symbiotic functions and is now complemented by additional symbionts. Though these cases break our view of aphids harbouring a single obligate endosymbiont, we know little about the extent, nature, and evolution of these associations across aphid subfamilies. Here, using metagenomics on 25 aphid species from nine subfamilies, re-assembly and re-annotation of 20 aphid symbionts previously sequenced, and 16S rRNA amplicon sequencing on 223 aphid samples (147 species from 12 subfamilies), we show that dual symbioses have evolved anew at least six times. We also show that these secondary co-obligate symbionts have typically evolved from facultative symbiotic taxa. Genome-based metabolic inference confirms interdependencies between Buchnera and its partners for the production of essential nutrients but shows contributions vary across pairs of co-obligate associates. Fluorescent in situ hybridisation microscopy shows a common bacteriocyte localisation of two newly acquired symbionts. Lastly, patterns of Buchnera genome evolution reveal that small losses affecting a few key genes can be the onset of these dual systems, while large gene losses can occur without any co-obligate symbiont acquisition. Hence, the Buchnera-aphid association, often thought of as exclusive, seems more flexible, with a few metabolic losses having recurrently promoted the establishment of a new co-obligate symbiotic partner.

genomics↗

A novel widespread MITE element in the repeat-rich genome of the Cardinium endosymbiont of the spider Oedothorax gibbosus

Free-living bacteria have evolved multiple times to become host-restricted endosymbionts. The transition from a free-living to a host-restricted lifestyle comes with a number of different genomic changes, including a massive loss of genes. In host-restricted endosymbionts, gene inactivation and genome reduction is facilitated by mobile genetic elements, mainly insertion sequences (ISs). ISs are small autonomous mobile elements, and one of, if not the most, abundant transposable elements in bacteria. Proliferation of ISs is common in some facultative endosymbionts, and is likely driven by the transmission bottlenecks, which increase the level of genetic drift. In the current study we present a manually curated genome annotation for a Cardinium endosymbiont of the dwarf spider Oedothorax gibbosus. Cardinium species are host-restricted endosymbionts that, similarly to Wolbachia spp., include strains capable of manipulating host reproduction. Through the focus on mobile elements, the annotation revealed a rampant spread of ISs, extending earlier observations in other Cardinium genomes. We found that a large proportion of IS elements are actually pseudogenised, with many displaying evidence of recent inactivation. Most notably, we describe the lineage-specific emergence and spread of a novel IS-derived Miniature Inverted repeat Transposable Element (MITE), likely being actively maintained by intact copies of its parental IS982-family element. This work highlights the relevance of manual curation of these repeat-rich endosymbiont genomes for the discovery of novel MITEs, as well as the possible role these understudied elements might play in genome streamlining.

genomics↗

One to host them all: genomics of the diverse bacterial endosymbionts of the spider Oedothorax gibbosus

Bacterial endosymbionts of the groups Wolbachia, Cardinium and Rickettsiaceae are well-known for their diverse effects on their arthropod hosts, ranging from mutualistic relationships to reproductive phenotypes. Here, we analyzed a unique system in which the dwarf spider Oedothorax gibbosus is co-infected with up to five different endosymbionts affiliated with Wolbachia, Candidatus Tisiphia (formerly Torix group Rickettsia), Cardinium, and Rhabdochlamydia. Using short-read genome sequencing data, we show that the endosymbionts are heterogeneously distributed among O. gibbosus populations and are frequently found co-infecting spider individuals. To study this intricate host-endosymbiont system on a genome resolved level, we used long-read sequencing to reconstruct closed genomes of the Wolbachia, Ca. Tisiphia and Cardinium endosymbionts. We provide insights in the ecology and evolution of the endosymbionts and shed light on the interactions with their spider host. We detected high quantities of transposable elements in all endosymbiont genomes and provide evidence that ancestors of the Cardinium, Ca. Tisiphia and Wolbachia endosymbionts have co-infected the same hosts in the past. Our findings contribute to broadening our knowledge about endosymbionts infecting one of the largest animal phyla on earth and show the usefulness of transposable elements as an evolutionary "contact-tracing" tool. Data summaryAll supporting data, code and protocols have been provided within the article or through supplementary data files. Seven supplementary figures and seven supplementary tables are available with the online version of this article. Sequencing data used in this study was generated and previously published by Hendrickx et al., 2021. Genome assemblies generated in this study have been deposited under the project PRJEB52003 at DDBJ/ENA/GenBank. The MAG of R. oedothoracis OV001 was deposited at DDBJ/ENA/GenBank under the sample SAMN28026840. The genome of Candidatus Rhabdochlamydia oedothoracis W744x776 was previously published by Halter et al., 2022 and is available at DDBJ/ENA/GenBank (accession: CP075587-CP075588). The collection of genomes and proteomes, all files for phylogenetic analyses including gene alignments, concatenated alignments, and tree files, and original output files of the HGT and SNP predictions used in this study are available at zenodo (https://doi.org/10.5281/zenodo.6362846).

genomics↗

Evolutionary recent dual obligatory symbiosis among adelgids indicates a transition between fungus and insect associated lifestyles

Adelgids (Insecta: Hemiptera: Adelgidae) form a small group of insects but harbor a surprisingly diverse set of bacteriocyte-associated endosymbionts, which suggest multiple replacement and acquisition of symbionts over evolutionary time. Specific pairs of symbionts have been associated with adelgid lineages specialized on different secondary host conifers. Using a metagenomic approach, we investigated the symbiosis of the Adelges laricis/tardus species complex containing betaproteobacterial ( Candidatus Vallotia tarda) and gammaproteobacterial ( Candidatus Profftia tarda) symbionts. Genomic characteristics and metabolic pathway reconstructions revealed that Vallotia and Profftia are evolutionary young endosymbionts, which complement each others role in essential amino acid production. Phylogenomic analyses and a high level of genomic synteny indicate an origin of the betaproteobacterial symbiont from endosymbionts of Rhizopus fungi. This evolutionary transition was accompanied with substantial loss of functions related to transcription regulation, secondary metabolite production, bacterial defense mechanisms, host infection and manipulation. The transition from fungus to insect endosymbionts extends our current framework about evolutionary trajectories of host-associated microbes.

microbiology↗

The protector within: Comparative genomics of APSE phages across aphids reveals rampant recombination and diverse toxin arsenals

Phages can fundamentally alter the physiology and metabolism of their hosts. While ubiquitous in the bacterial world, they have seldom been described among endosymbiotic bacteria. One notable exception in the APSE phage that is found associated with the gammaproteobacterial Hamiltonella defensa, hosted by several insect species. This secondary facultative endosymbiont is not necessary for the survival of its hosts but can infect certain individuals or even whole populations. Its infection in aphids is often associated with protection against parasitoid wasps. This protective phenotype has actually been linked to the infection of the symbiont strain with an APSE, which carries a toxin cassette that varies among so-called "types". In the present work, we seek to expand our understanding of the diversity of APSE phages as well as the relations of their Hamiltonella hosts. For this, we assembled and annotated the full genomes of 16 APSE phages infecting Hamiltonella symbionts across 10 insect species. Molecular and phylogenetic analyses suggest that recombination has occurred repeatedly among lineages. Comparative genomics of the phage genomes revealed two variable regions that are useful for phage typing. Additionally, we find that mobile elements could play a role in the acquisition of new genes in the toxin cassette. Altogether, we provide an unprecedented view of APSE diversity and their genome evolution across aphids. This genomic investigation will provide a valuable resource for the design and interpretation of experiments aiming at understanding the protective phenotype these phages confer to their insect hosts.

genomics↗

Cytoplasmic incompatibility between Old and New World populations of a tramp ant

As we enter the Anthropocene, the evolutionary dynamics of species will change drastically, and as yet unpredictably, due to human activity. Already today, increases in global human traffic have resulted in the rapid spread of species to new areas, leading to the formation of geographically isolated populations. These go on to evolve in allopatry, which can lead to reproductive isolation, and potentially, the formation of new species. Surprisingly, little is known about such eco-evolutionary processes in ants, even though numerous invasive ant species are globally distributed in geographically isolated populations. Here, we describe the first case of cytoplasmic incompatibility (CI) between populations of a cosmotropic distributed tramp ant with Asian roots, Cardiocondyla obscurior, which has acquired a novel Wolbachia strain in the New World. Our study uncovers the first symbiont-induced mechanism of reproductive isolation in ants, providing a novel perspective on the biology of globally distributed ants.

evolutionary biology↗

No evidence for Wolbachia as a nutritional co-obligate endosymbiont in the aphid Pentalonia nigronervosa

Obligate symbiotic associations are present in a wide variety of animals with a nutrient-restricted diet. Aphids (hemiptera: Aphididae) almost-universally host Buchnera aphidicola bacteria in a specialised organs (called bacteriomes). These bacteria supply the aphid with essential nutrients lacking from their diet (i.e. essential amino acids and some B vitamins). Some aphid lineages, such as species from the Lacninae subfamily, have evolved co-obligate associations with secondary endosymbionts, deriving from a loss of biotin-and riboflavin-biosynthetic genes. In this study I re-analyse previously published sequencing data from the banana aphid Pentalonia nigronervosa. I show that the metabolic inference results from De Clerck et al. (2015) are incorrect and possibly arise from the use of inadequate methods. Additionally, I discuss how the biased interpretation of their antibiotic treatment analyses together with the incorrect metabolic inference resulted in the erroneous suggestion \"that a co-obligatory symbiosis between B. aphidicola and Wolbachia occurs in the banana aphid\".

genomics↗

Serial horizontal transfer of vitamin-biosynthetic genes enables the establishment of new nutritional symbionts in aphids' di-symbiotic systems

Many insects with a nutrient-restricted diet depend on obligate mutualistic bacteria for the provisioning of essential nutrients lacking from their food source, namely essential amino acids and B vitamins. Most aphids (Hemiptera: Aphididae), whose diet consists of phloem, rely on the bacterial endosymbiont Buchnera for the supply of the aforementioned compounds. However, in some aphid lineages Buchnera have lost the capability of producing these nutrients and thus the symbiotic consortium has accommodated an extra bacterial partner to supplement Buchneras deficiencies. In this work, we explore the di-symbiotic nutritional endosymbiosis of a group of Cinara aphids which has been found to harbour both Buchnera and an Erwinia-related symbiont. Using fluorescence in situ hybridisation, we have located this symbiont to the bacteriome where it inhabits its own bacteriocytes. Through whole-genome sequencing of the endosymbionts of 9 species of Erwinia-associated Cinara aphids, we have found that Ewrinia genomes are highly syntenic and all show significant genome reduction. Additionally, Erwinia symbionts display phylogenetic congruency with Buchnera, suggesting long-term co-divergence. Most significantly, we found that not only is Erwinia capable of complementing Buchneras auxotrophies, but that the genes involved in the biosynthesis of two B vitamins have actually been horizontally acquired from a Sodalis-related bacterium. Finally, this B-vitamin biosynthetic genes have been further transferred to a new Hamiltonella co-obligate symbiont in a specific Cinara lineage, thus displaying a tri-symbiotic system. These results highlight the important role horizontal gene transfer plays in the establishment of new obligate nutritional symbionts.

genomics↗

A Freeloader?: The Highly Eroded Yet Big-Genomed Serratia symbiotica symbiont of Cinara strobi

Genome reduction is pervasive among maternally-inherited bacterial endosymbionts. This genome reduction can eventually lead to serious deterioration of essential metabolic pathways, thus rendering an obligate endosymbiont unable to provide essential nutrients to its host. This loss of essential pathways can lead to either symbiont complementation (sharing of the nutrient production with a novel co-obligate symbiont) or symbiont replacement (complete takeover of nutrient production by the novel symbiont). However, the process by which these two evolutionary events happen remains somewhat enigmatic by the lack of examples of intermediate stages of this process. Cinara aphids (Hemiptera: Aphididae) typically harbour two obligate bacterial symbionts: Buchnera and Serratia symbiotica. However, the latter has been replaced by different bacterial taxa in specific lineages, and thus species within this aphid lineage could provide important clues into the process of symbiont replacement. In the present study, using 16S rRNA high-throughput amplicon sequencing, we determined that the aphid Cinara strobi harbours not two, but three fixed bacterial symbionts: Buchnera aphidicola, a Sodalis sp., and S. symbiotica. Through genome assembly and genome-based metabolic inference, we have found that only the first two symbionts (Buchnera and Sodalis) actually contribute to the hosts supply of essential nutrients while S. symbiotica has become unable to contribute towards this task. We found that S. symbiotica has a rather large and highly eroded genome which codes only for a few proteins and displays extensive pseudogenisation. Thus, we propose an ongoing symbiont replacement within C. strobi, in which a once competent\" S. symbiotica does no longer contribute towards the beneficial association. These results suggest that in dual symbiotic systems, when a substitute co-symbiont is available, genome deterioration can precede genome reduction and a symbiont can be maintained despite the apparent lack of benefit to its host.

genomics↗

Buchnera has changed flatmate but the repeated replacement of co-obligate symbionts is not associated with the ecological expansions of their aphid hosts

Symbiotic associations with bacteria have facilitated important evolutionary transitions in insects and resulted in long-term obligate interactions. Recent evidence suggests that these associations are not always evolutionarily stable and that symbiont replacement and/or supplementation of an obligate symbiosis by an additional bacterium has occurred during the history of many insect groups. Yet, the factors favoring one symbiont over another in this evolutionary dynamic are not well understood; progress has been hindered by our incomplete understanding of the distribution of symbionts across phylogenetic and ecological contexts. While many aphids are engaged into an obligate symbiosis with a single Gammaproteobacterium, Buchnera aphidicola, in species of the Lachninae subfamily, this relationship has evolved into a \"menage a trois\", in which Buchnera is complemented by a cosymbiont, usually Serratia symbiotica. Using deep sequencing of 16S rRNA bacterial genes from 128 species of Cinara (the most diverse Lachninae genus), we reveal a highly dynamic dual symbiotic system in this aphid lineage. Most species host both Serratia and Buchnera but, in several clades, endosymbionts related to Sodalis, Erwinia or an unnamed member of the Enterobacteriaceae have replaced Serratia. Endosymbiont genome sequences from four aphid species+confirm that these coresident symbionts fulfill essential metabolic functions not ensured by Buchnera. We further demonstrate through comparative phylogenetic analyses that co-symbiont replacement is not associated with the adaptation of aphids to new ecological conditions. We propose that symbiont succession was driven by factors intrinsic to the phenomenon of endosymbiosis, such as rapid genome deterioration or competitive interactions between bacteria with similar metabolic capabilities.

evolutionary biology↗