Characterization of host-symbiont molecular interactions and evolutionary relationships in the gutless oligochaete Olavius algarvensis

The marine gutless oligochaete O. algarvensis lives in obligate symbiosis with a chemosynthetic bacterial consortium that exclusively provides it with nutrition. This thesis contributes to a better understanding of how this essential symbiosis is maintained, both on a physiological and immunological level (chapter IV), as well as from an evolutionary perspective (chapter II). This is addressed by using metagenomics, -proteomics and -transcriptomics to better understand symbiont transmission, diversity, co-divergent evolution and the molecular adaptations of the host that allow it to intimately associate with a diverse and physiologically demanding chemosynthetic consortium (anoxia and noxious substances). Furthermore, chapter III provides the first functional genomic description of the spirochaetal symbiont of O. algarvensis, showing that it is most likely a beneficial symbiont involved in the utilization and funneling of environmentally derived organic nutrients into the symbiosis

High-Quality Draft Genome Sequences of Two Deltaproteobacterial Endosymbionts, Delta1a and Delta1b, from the Uncultured Sva0081 Clade, Assembled from Metagenomes of the Gutless Marine Worm Olavius algarvensis

Here, we present high-quality metagenome-assembled genome sequences of two closely related deltaproteobacterial endosymbionts from the gutless marine worm Olavius algarvensis (Annelida). The first is an improved draft genome sequence of the previously described sulfate-reducing symbiont Delta1. The second is from a closely related, recently discovered symbiont of O. algarvensis

High-Quality Draft Genome Sequences of the Uncultured Delta3 Endosymbiont (Deltaproteobacteria) Assembled from Metagenomes of the Gutless Marine Worm Olavius algarvensis

Here, we present two high-quality, draft metagenome-assembled genomes of deltaproteobacterial OalgDelta3 endosymbionts from the gutless marine worm Olavius algarvensis. Their 16S rRNA gene sequences share 98% identity with Delta3 endosymbionts of related host species Olavius ilvae (GenBank accession no. AJ620501) and Inanidrilus exumae (GenBank accession no. FM202060), for which no symbiont genomes are available

Fidelity varies in the symbiosis between a gutless marine worm and its microbial consortium

Background: Many animals live in intimate associations with a species-rich microbiome. A key factor in maintaining these beneficial associations is fidelity, defined as the stability of associations between hosts and their microbiota over multiple host generations. Fidelity has been well studied in terrestrial hosts, particularly insects, over longer macroevolutionary time. In contrast, little is known about fidelity in marine animals with species-rich microbiomes at short microevolutionary time scales, that is at the level of a single host population. Given that natural selection acts most directly on local populations, studies of microevolutionary partner fidelity are important for revealing the ecological and evolutionary processes that drive intimate beneficial associations within animal species. Results: In this study on the obligate symbiosis between the gutless marine annelid Olavius algarvensis and its consortium of seven co-occurring bacterial symbionts, we show that partner fidelity varies across symbiont species from strict to absent over short microevolutionary time. Using a low-coverage sequencing approach that has not yet been applied to microbial community analyses, we analysed the metagenomes of 80 O. algarvensis individuals from the Mediterranean and compared host mitochondrial and symbiont phylogenies based on single-nucleotide polymorphisms across genomes. Fidelity was highest for the two chemoautotrophic, sulphur-oxidizing symbionts that dominated the microbial consortium of all O. algarvensis individuals. In contrast, fidelity was only intermediate to absent in the sulphate-reducing and spirochaetal symbionts with lower abundance. These differences in fidelity are likely driven by both selective and stochastic forces acting on the consistency with which symbionts are vertically transmitted. Conclusions: We hypothesize that variable degrees of fidelity are advantageous for O. algarvensis by allowing the faithful transmission of their nutritionally most important symbionts and flexibility in the acquisition of other symbionts that promote ecological plasticity in the acquisition of environmental resources

A critical review of the Exit-Voice-Loyalty-Neglect literature: limitations, key challenges and directions for future research

The study of human behaviour holds a prominent role in organizational behavior literature. For almost 45 years, the exit, voice, loyalty and neglect typology has attracted scholars' interest and has been linked to employee responses towards dissatisfaction and problematic events in the workplace. This paper reviews the literature and identifies and addresses key theoretical and methodological deficiencies that the exit, voice, loyalty and neglect typology faces that have been either ignored or undeveloped. Moreover, by unpicking this typology as currently portrayed in the existing literature, it proposes key challenges that need to be addressed and provides directions for future research

Charakterisierung von molekularen Wirt - Symbionten Interaktionen und evolutionären Beziehungen im darmlosen Oligochaeten Olavius algarvensis

The marine gutless oligochaete O. algarvensis lives in obligate symbiosis with a chemosynthetic bacterial consortium that exclusively provides it with nutrition. This thesis contributes to a better understanding of how this essential symbiosis is maintained, both on a physiological and immunological level (chapter IV), as well as from an evolutionary perspective (chapter II). This is addressed by using metagenomics, -proteomics and -transcriptomics to better understand symbiont transmission, diversity, co-divergent evolution and the molecular adaptations of the host that allow it to intimately associate with a diverse and physiologically demanding chemosynthetic consortium (anoxia and noxious substances). Furthermore, chapter III provides the first functional genomic description of the spirochaetal symbiont of O. algarvensis, showing that it is most likely a beneficial symbiont involved in the utilization and funneling of environmentally derived organic nutrients into the symbiosis

Metagenomic data for gutless oligochaete symbionts (2017)

This list contains accession numbers to: -Metatranscriptomic data of gutless oligochaete Olavius algarvensisworms depositied in European Nucleotide Archive ENA -Metaproteomic data of gutless oligochaete Olavius algarvensisworms deposited in proteomics data repositories -Draft genomes of endosymbionts from various gutless oligochaete hosts, in submission process. If you are interested in these datasets, please let us know

High-Quality Draft Genome Sequences of the Uncultured Delta3 Endosymbiont (Deltaproteobacteria) Assembled from Metagenomes of the Gutless Marine Worm Olavius algarvensis.

Here, we present two high-quality, draft metagenome-assembled genomes of deltaproteobacterial OalgDelta3 endosymbionts from the gutless marine worm Olavius algarvensis Their 16S rRNA gene sequences share 98% identity with Delta3 endosymbionts of related host species Olavius ilvae (GenBank accession no. AJ620501) and Inanidrilus exumae (GenBank accession no. FM202060), for which no symbiont genomes are available

Additional file 3: Table S14. of Transcriptomic and proteomic insights into innate immunity and adaptations to a symbiotic lifestyle in the gutless marine worm Olavius algarvensis

Subcellular localization evidence of host digestive proteins. (XLSX 17 kb