DOCSLIB.ORG

Catenulida, Platyhelminthes) and Its Intracellular Symbionts

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Catenulida, Platyhelminthes) and Its Intracellular Symbionts Zoomorphology (2011) 130:261–271 DOI 10.1007/s00435-011-0135-y ORIGINAL PAPER Microanatomy of the trophosome region of Paracatenula cf. polyhymnia (Catenulida, Platyhelminthes) and its intracellular symbionts Nikolaus Leisch • Ulrich Dirks • Harald R. Gruber-Vodicka • Markus Schmid • Wolfgang Sterrer • Jo¨rg A. Ott Received: 13 June 2011 / Revised: 11 August 2011 / Accepted: 13 August 2011 / Published online: 14 September 2011 Ó The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Marine catenulid platyhelminths of the genus morphologically reduced and most likely not functional. Paracatenula lack mouth, pharynx and gut. They live in a Cells containing needle-like inclusions in the reference symbiosis with intracellular bacteria which are restricted to species Paracatenula polyhymnia Sterrer and Rieger, 1974 the body region posterior to the brain. The symbiont- were thought to be sperm, and the inclusions interpreted as housing cells (bacteriocytes) collectively form the tropho- the sperm nucleus. Our analysis of similar cells and their some tissue, which functionally replaces the digestive tract. inclusions by EDX and Raman microspectroscopy docu- It constitutes the largest part of the body and is the most ments an inorganic spicule consisting of a unique magne- important synapomorphy of this group. While some other sium–phosphate compound. Furthermore, we identify the features of the Paracatenula anatomy have already been neoblast stem cells located underneath the epidermis. analyzed, an in-depth analysis of the trophosome region Except for the modifications due to the symbiotic lifestyle was missing. Here, we identify and characterize the com- and the enigmatic spicule cells, the organization of Para- position of the trophosome and its surrounding tissue by catenula cf. polyhymnia conforms to that of the Catenulida analyzing series of ultra-thin cross-sections of the species in all studied aspects. Therefore, this species represents an Paracatenula cf. polyhymnia. For the first time, a proto- excellent model system for further studies of host adapta- nephridium is detected in a Paracatenula species, but it is tion to an obligate symbiotic lifestyle. Keywords Platyhelminthes Á Symbiosis Á Paracatenula Á Ultrastructure Á Trophosome Communicated by T. Bartolomaeus. Introduction Electronic supplementary material The online version of this article (doi:10.1007/s00435-011-0135-y) contains supplementary Morphological and molecular evidence indicates that the material, which is available to authorized users. Catenulida are the most basal group of Platyhelminthes (Ehlers 1985; Larsson and Jondelius 2008; Philippe et al. N. Leisch (&) Á U. Dirks Á H. R. Gruber-Vodicka Á J. A. Ott 2011). Most species of the order are limnic, but the Ret- Department of Marine Biology, University of Vienna, ronectidae were initially reported to be exclusively marine Althanstraße 14, 1090 Vienna, Austria (Sterrer and Rieger 1974) and containing two genera, e-mail: [email protected] Retronectes and Paracatenula. Noren˜a and Faubel (1996) M. Schmid described a third genus—Myoretronectes from a limnic Department of Microbial Ecology, University of Vienna, habitat. While Retronectes species and most limnic Cate- Althanstraße 14, 1090 Vienna, Austria nulida have been reported from tropical to cold temperate regions, the members of the genus Paracatenula have been W. Sterrer Bermuda Aquarium, Natural History Museum and Zoo (BAMZ), found only in warm-temperate to tropical regions. All Flatts Village, Bermuda species of the genus Paracatenula lack mouth, pharynx and 123 262 Zoomorphology (2011) 130:261–271 Fig. 1 Habitus of Paracatenula cf. polyhymnia. a Light microscope micrograph, dotted rectangle represents area of serial section. b Phase contrast micrograph of the anterior region. tr trophosome region, ro rostrum, sp spicule, ba bacteria gut (Sterrer and Rieger 1974). Instead, the largest part of likely satisfy most or even all of the nutritional demands of the body is made up of a tissue composed of bacteriocytes, the host. cells harboring intracellular bacterial symbionts (Ott et al. Platyhelminthes are known for their unique system of 1982). This tissue is called the trophosome (Dirks et al. totipotent stem cells—the neoblasts—from which all cells 2011), in functional analogy to the trophosome found in the arise and which are the only cells showing mitotic activity mouthless Siboglinidae (Annelida) (Fig. 1). All species of (Ladurner et al. 2000; Peter et al. 2004). On the ultra- the genus Paracatenula inhabit the interstitial space of structural level, they can be identified by the following shallow-water subtidal sands. In this habitat, chemoauto- structures: (1) a highly active nucleus displaying a check- trophic primary production by prokaryotes oxidizing erboard pattern, (2) many mitochondria, (3) free ribosomes reduced sulfur compounds plays a vital role comparable to and (4) chromatoid bodies (Hori 1982). The chromatoid hydrothermal hot vents, cold seeps and whale- and wood- bodies are electron-dense structures that can be found close falls. Mutualistic symbioses with sulfur-oxidizing bacteria to the nuclear envelope and mitochondria. They contain have been documented from these habitats for many taxa of RNA and proteins and are essential for the cytodifferenti- eukaryotes, including ciliates, nematodes, mollusks and ation process (Auladell et al. 1993). The ultrastructural annelids. Most of these show profound morphological investigation of the neoblast also gave the opportunity to adaptations to the symbiotic lifestyle, such as reduction in add to the knowledge of the anatomy of this exceptional mouth and gut, specialized symbiont-housing tissues and representative of the Catenulids, a group that is less well reduction in excretory organs. The symbionts belong to studied than many other platyhelminth taxa (Bedini and several different clades in the Alpha-, Gamma-orEpsi- Papi 1974; Ehlers 1985; Hooge 2001; Moraczweski 1981; lonproteobacteria (Dubilier et al. 2008; Gruber-Vodicka Rieger et al. 1991; Rohde 2001). et al. 2011). The association between Paracatenula species While several studied features of Paracatenula, such as and the thiotrophic Alphaproteobacteria Candidatus Rie- muscle arrangement (Hooge 2001) or brain organization geria likely dates back to the early days of platyhelminth (Sterrer and Rieger 1974), are typical for Catenulida, the evolution more than 500 million years ago (Gruber-Vodi- synapomorphy of this genus is the lack of a digestive tract cka et al. 2011). Similar to what has been shown for other and its functional replacement by the trophosome tissue. meiofaunal hosts of sulfur-oxidizing bacteria, e.g., nema- We therefore focused on this region in Paracatenula cf. todes (Ott et al. 1991) or gutless oligochaetes (Giere et al. polyhymnia, using serial-sectioning-based transmission 1991), the animals probably migrate through the redox electron microscopic reconstructions, scanning electron potential gradient in the top 5–15 cm layer of the sediment microscopy, together with energy dispersive X-ray analysis and thus could provide their symbionts with both sulfide and Raman microspectroscopy techniques. We character- and electron acceptors such as nitrate or oxygen. In ized the tissue composition and resolved enigmatic struc- endosymbiotic associations, such as in the genus Paraca- tures that are unique to these worms, such as the spicule- tenula, the host additionally provides a sheltered and stable shaped inclusions, previously regarded as sperm, which are environment to its symbionts. In return, the symbionts in fact of mineral nature (‘‘sp’’ in Fig. 1b). 123 Zoomorphology (2011) 130:261–271 263 Materials and methods Genesis software (Ver. 5.11 EDAX). Readings from the carbon-coated stub served as a signal background for our Specimens were collected during two field trips (October measurements. For Raman microspectroscopy, only indi- 2009, June 2010) in Dahab, Egypt. Sampling took place in viduals that had not been relaxed with magnesium chloride ‘‘Eel Garden’’ (28°30019.9700N, 34°31018.5200E; 8 m depth) were used. Both semi-thin sections (2.5 lm) of resin- and ‘‘Napoleon Reef’’ (28°28013.8300N, 34°30032.5100E; 1 m embedded specimens and complete spicules were mounted depth). Specimens were extracted from the fine to medium on a calcium fluoride slide, and analysis was performed sand by shaking it with filtered seawater and decanting the with a LabRAM HR800 confocal Raman microscope supernatant through a 32-lm mesh sieve. The content of the (Horiba Jobin–Yvon, Bensheim, Germany), utilizing a net was transferred into a petri dish, and approximately 200 532-nm Nd: YAG laser (50mW). Spicules were selected specimens were sorted by morphological features under a using a 509 objective, and the signal was acquired over a dissecting microscope. Paracatenula cf. polyhymnia was period of 5 s using a D0.6 intensity filter (25% laser identified by the presence of spicules similar to those of intensity). The pinhole of the Peltier-cooled CCD detector Paracatenula polyhymnia, reported from the Western was adjusted to 250 lm (optical slice 4.6 lm). Spectra Atlantic (Sterrer and Rieger 1974). Reference material for were measured between 300 and 2,000 cm-1, the range P. cf. polyhymnia has been deposited in the Natural History where the compounds identified with the EDX showed the Museum Vienna under the numbers NHM Wien/Vienna Ev most characteristic peaks. The spectra were acquired, varia 20.109 and NHM
Load more

Recommended publications
  • Tube Worm Riftia Pachyptila to Severe Hypoxia
    l MARINE ECOLOGY PROGRESS SERIES Vol. 174: 151-158,1998 Published November 26 Mar Ecol Prog Ser Metabolic responses of the hydrothermal vent tube worm Riftia pachyptila to severe hypoxia Cordelia ~rndt',~.*,Doris Schiedek2,Horst Felbeckl 'University of California San Diego, Scripps Institution of Oceanography. La Jolla. California 92093-0202. USA '~alticSea Research Institute at the University of Rostock, Seestrasse 15. D-181 19 Rostock-Warnemuende. Germany ABSTRACT: The metabolic capabilit~esof the hydrothermal vent tube worm Riftia pachyptila to toler- ate short- and long-term exposure to hypoxia were investigated After incubating specimens under anaerobic conditions the metabolic changes in body fluids and tissues were analyzed over time. The tube worms tolerated anoxic exposure up to 60 h. Prior to hypoxia the dicarboxylic acid, malate, was found in unusually high concentrations in the blood (up to 26 mM) and tissues (up to 5 pm01 g-' fresh wt). During hypoxia, most of the malate was degraded very quickly, while large quantities of succinate accumulated (blood: about 17 mM; tissues: about 13 pm01 g-l fresh wt). Volatile, short-chain fatty acids were apparently not excreted under these conditions. The storage compound, glycogen, was mainly found in the trophosome and appears to be utilized only during extended anaerobiosis. The succinate formed during hypoxia does not account for the use of malate and glycogen, which possibly indicates the presence of yet unidentified metabolic end products. Glutamate concentration in the trophosome decreased markedly durlng hypoxia, presumably due to a reduction in the autotrophic function of the symb~ontsduring hypoxia. In conclusion, R. pachyptila is phys~ologicallywell adapted to the oxygen fluctuations freq.uently occurring In the vent habitat.
    [Show full text]
  • Old Woman Creek National Estuarine Research Reserve Management Plan 2011-2016
    Old Woman Creek National Estuarine Research Reserve Management Plan 2011-2016 April 1981 Revised, May 1982 2nd revision, April 1983 3rd revision, December 1999 4th revision, May 2011 Prepared for U.S. Department of Commerce Ohio Department of Natural Resources National Oceanic and Atmospheric Administration Division of Wildlife Office of Ocean and Coastal Resource Management 2045 Morse Road, Bldg. G Estuarine Reserves Division Columbus, Ohio 1305 East West Highway 43229-6693 Silver Spring, MD 20910 This management plan has been developed in accordance with NOAA regulations, including all provisions for public involvement. It is consistent with the congressional intent of Section 315 of the Coastal Zone Management Act of 1972, as amended, and the provisions of the Ohio Coastal Management Program. OWC NERR Management Plan, 2011 - 2016 Acknowledgements This management plan was prepared by the staff and Advisory Council of the Old Woman Creek National Estuarine Research Reserve (OWC NERR), in collaboration with the Ohio Department of Natural Resources-Division of Wildlife. Participants in the planning process included: Manager, Frank Lopez; Research Coordinator, Dr. David Klarer; Coastal Training Program Coordinator, Heather Elmer; Education Coordinator, Ann Keefe; Education Specialist Phoebe Van Zoest; and Office Assistant, Gloria Pasterak. Other Reserve staff including Dick Boyer and Marje Bernhardt contributed their expertise to numerous planning meetings. The Reserve is grateful for the input and recommendations provided by members of the Old Woman Creek NERR Advisory Council. The Reserve is appreciative of the review, guidance, and council of Division of Wildlife Executive Administrator Dave Scott and the mapping expertise of Keith Lott and the late Steve Barry.
    [Show full text]
  • (1104L) Animal Kingdom Part I
    (1104L) Animal Kingdom Part I By: Jeffrey Mahr (1104L) Animal Kingdom Part I By: Jeffrey Mahr Online: < http://cnx.org/content/col12086/1.1/ > OpenStax-CNX This selection and arrangement of content as a collection is copyrighted by Jerey Mahr. It is licensed under the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/). Collection structure revised: October 17, 2016 PDF generated: October 17, 2016 For copyright and attribution information for the modules contained in this collection, see p. 58. Table of Contents 1 (1104L) Animals introduction ....................................................................1 2 (1104L) Characteristics of Animals ..............................................................3 3 (1104L)The Evolutionary History of the Animal Kingdom ..................................11 4 (1104L) Phylum Porifera ........................................................................23 5 (1104L) Phylum Cnidaria .......................................................................31 6 (1104L) Phylum Rotifera & Phylum Platyhelminthes ........................................45 Glossary .............................................................................................53 Index ................................................................................................56 Attributions .........................................................................................58 iv Available for free at Connexions <http://cnx.org/content/col12086/1.1> Chapter 1 (1104L) Animals introduction1
    [Show full text]
  • Biological and Chemical Diversity of Bacteria Associated with a Marine Flatworm
    Article Biological and Chemical Diversity of Bacteria Associated with a Marine Flatworm Hui-Na Lin 1,2,†, Kai-Ling Wang 1,3,†, Ze-Hong Wu 4,5, Ren-Mao Tian 6, Guo-Zhu Liu 7 and Ying Xu 1,* 1 Shenzhen Key Laboratory of Marine Bioresource & Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China; [email protected] (H.-N.L.); [email protected] (K.-L.W.) 2 School of Life Sciences, Xiamen University, Xiamen 361102, China 3 Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China 4 The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen 518033, China; [email protected] 5 Integrated Chinese and Western Medicine Postdoctoral Research Station, Jinan University, Guangzhou 510632, China 6 Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China; [email protected] 7 HEC Research and Development Center, HEC Pharm Group, Dongguan 523871, China; [email protected] * Correspondence: [email protected]; Tel.: +86-755-26958849; Fax: +86-755-26534274 † These authors contributed equally to this work. Received: 20 July 2017; Accepted: 29 August 2017; Published: 1 September 2017 Abstract: The aim of this research is to explore the biological and chemical diversity of bacteria associated with a marine flatworm Paraplanocera sp., and to discover the bioactive metabolites from culturable strains. A total of 141 strains of bacteria including 45 strains of actinomycetes and 96 strains of other bacteria were isolated, identified and fermented on a small scale.
    [Show full text]
  • Is the Turbellaria Polyphyletic?
    Is the Turbellaria polyphyletic? Julian P. S. Smith, III,' Seth Teyler' & Reinhard M . Rieger2 'Department of Zoology, University of Maine, Orono, ME 04469, USA 2Department of Biology, University of North Carolina, Chapel Hill, NC 27514, USA Keywords: Tirbellaria, phylogenetic systematics, Platyhelminthes, polyphyly, ultrastructure, epidermis, cilia Abstract Within the last two decades, syntheses of both light-microscopic and ultrastructural characters have shown that there are three well-defined monophyletic groups within the Platyhelminthes : 1) the Catenulidale, 2) the Nemertodermatida-Acoela, and 3) the Haplopharyngida-Macrostomida-Polycladida-Neoophora (+ parasit- ic platyhelminth classes) . However, the relationships among these three groups are problematic . The possible apomorphies that would unite them are either not true homologues (i.e. frontal organ), are mutually conflict- ing (i.e. 9+1 axoneme in spermatozoa vs . biflagellate spermatozoa, epidermal ciliary rootlet structure, and protonephridia), or are unrooted with any outgroup and hence untestable or uncertain as apomorphies (pro- tonephridia, mode of epidermal replacement, absence of accessory centrioles on cilia) . The chief obstacle to deciphering the relationships of these groups is the lack of information on them ; presently available infor- mation is insufficient to test potential synapomorphies and insufficient also to allow agreement upon a nar- rowly defined outgroup for the Turbellaria . A view consistent with the present evidence (and admittedly an unsatisfactory
    [Show full text]
  • Nanosims and Tissue Autoradiography Reveal Symbiont Carbon fixation and Organic Carbon Transfer to Giant Ciliate Host
    The ISME Journal (2018) 12:714–727 https://doi.org/10.1038/s41396-018-0069-1 ARTICLE NanoSIMS and tissue autoradiography reveal symbiont carbon fixation and organic carbon transfer to giant ciliate host 1 2 1 3 4 Jean-Marie Volland ● Arno Schintlmeister ● Helena Zambalos ● Siegfried Reipert ● Patricija Mozetič ● 1 4 2 1 Salvador Espada-Hinojosa ● Valentina Turk ● Michael Wagner ● Monika Bright Received: 23 February 2017 / Revised: 3 October 2017 / Accepted: 9 October 2017 / Published online: 9 February 2018 © The Author(s) 2018. This article is published with open access Abstract The giant colonial ciliate Zoothamnium niveum harbors a monolayer of the gammaproteobacteria Cand. Thiobios zoothamnicoli on its outer surface. Cultivation experiments revealed maximal growth and survival under steady flow of high oxygen and low sulfide concentrations. We aimed at directly demonstrating the sulfur-oxidizing, chemoautotrophic nature of the symbionts and at investigating putative carbon transfer from the symbiont to the ciliate host. We performed pulse-chase incubations with 14C- and 13C-labeled bicarbonate under varying environmental conditions. A combination of tissue autoradiography and nanoscale secondary ion mass spectrometry coupled with transmission electron microscopy was used to fi 1234567890();,: follow the fate of the radioactive and stable isotopes of carbon, respectively. We show that symbiont cells x substantial amounts of inorganic carbon in the presence of sulfide, but also (to a lesser degree) in the absence of sulfide by utilizing internally stored sulfur. Isotope labeling patterns point to translocation of organic carbon to the host through both release of these compounds and digestion of symbiont cells. The latter mechanism is also supported by ultracytochemical detection of acid phosphatase in lysosomes and in food vacuoles of ciliate cells.
    [Show full text]
  • Genomic Adaptations to Chemosymbiosis in the Deep-Sea Seep-Dwelling Tubeworm Lamellibrachia Luymesi Yuanning Li1,2* , Michael G
    Li et al. BMC Biology (2019) 17:91 https://doi.org/10.1186/s12915-019-0713-x RESEARCH ARTICLE Open Access Genomic adaptations to chemosymbiosis in the deep-sea seep-dwelling tubeworm Lamellibrachia luymesi Yuanning Li1,2* , Michael G. Tassia1, Damien S. Waits1, Viktoria E. Bogantes1, Kyle T. David1 and Kenneth M. Halanych1* Abstract Background: Symbiotic relationships between microbes and their hosts are widespread and diverse, often providing protection or nutrients, and may be either obligate or facultative. However, the genetic mechanisms allowing organisms to maintain host-symbiont associations at the molecular level are still mostly unknown, and in the case of bacterial-animal associations, most genetic studies have focused on adaptations and mechanisms of the bacterial partner. The gutless tubeworms (Siboglinidae, Annelida) are obligate hosts of chemoautotrophic endosymbionts (except for Osedax which houses heterotrophic Oceanospirillales), which rely on the sulfide- oxidizing symbionts for nutrition and growth. Whereas several siboglinid endosymbiont genomes have been characterized, genomes of hosts and their adaptations to this symbiosis remain unexplored. Results: Here, we present and characterize adaptations of the cold seep-dwelling tubeworm Lamellibrachia luymesi, one of the longest-lived solitary invertebrates. We sequenced the worm’s ~ 688-Mb haploid genome with an overall completeness of ~ 95% and discovered that L. luymesi lacks many genes essential in amino acid biosynthesis, obligating them to products provided by symbionts. Interestingly, the host is known to carry hydrogen sulfide to thiotrophic endosymbionts using hemoglobin. We also found an expansion of hemoglobin B1 genes, many of which possess a free cysteine residue which is hypothesized to function in sulfide binding.
    [Show full text]
  • Dear Author, Here Are the Proofs of Your Article. • You Can Submit Your
    Dear Author, Here are the proofs of your article. • You can submit your corrections online, via e-mail or by fax. • For online submission please insert your corrections in the online correction form. Always indicate the line number to which the correction refers. • You can also insert your corrections in the proof PDF and email the annotated PDF. • For fax submission, please ensure that your corrections are clearly legible. Use a fine black pen and write the correction in the margin, not too close to the edge of the page. • Remember to note the journal title, article number, and your name when sending your response via e-mail or fax. • Check the metadata sheet to make sure that the header information, especially author names and the corresponding affiliations are correctly shown. • Check the questions that may have arisen during copy editing and insert your answers/ corrections. • Check that the text is complete and that all figures, tables and their legends are included. Also check the accuracy of special characters, equations, and electronic supplementary material if applicable. If necessary refer to the Edited manuscript. • The publication of inaccurate data such as dosages and units can have serious consequences. Please take particular care that all such details are correct. • Please do not make changes that involve only matters of style. We have generally introduced forms that follow the journal’s style. Substantial changes in content, e.g., new results, corrected values, title and authorship are not allowed without the approval of the responsible editor. In such a case, please contact the Editorial Office and return his/her consent together with the proof.
    [Show full text]
  • Chemosynthetic Symbiont with a Drastically Reduced Genome Serves As Primary Energy Storage in the Marine Flatworm Paracatenula
    Chemosynthetic symbiont with a drastically reduced genome serves as primary energy storage in the marine flatworm Paracatenula Oliver Jäcklea, Brandon K. B. Seaha, Målin Tietjena, Nikolaus Leischa, Manuel Liebekea, Manuel Kleinerb,c, Jasmine S. Berga,d, and Harald R. Gruber-Vodickaa,1 aMax Planck Institute for Marine Microbiology, 28359 Bremen, Germany; bDepartment of Geoscience, University of Calgary, AB T2N 1N4, Canada; cDepartment of Plant & Microbial Biology, North Carolina State University, Raleigh, NC 27695; and dInstitut de Minéralogie, Physique des Matériaux et Cosmochimie, Université Pierre et Marie Curie, 75252 Paris Cedex 05, France Edited by Margaret J. McFall-Ngai, University of Hawaii at Manoa, Honolulu, HI, and approved March 1, 2019 (received for review November 7, 2018) Hosts of chemoautotrophic bacteria typically have much higher thrive in both free-living environmental and symbiotic states, it is biomass than their symbionts and consume symbiont cells for difficult to attribute their genomic features to either functions nutrition. In contrast to this, chemoautotrophic Candidatus Riegeria they provide to their host, or traits that are necessary for envi- symbionts in mouthless Paracatenula flatworms comprise up to ronmental survival or to both. half of the biomass of the consortium. Each species of Paracate- The smallest genomes of chemoautotrophic symbionts have nula harbors a specific Ca. Riegeria, and the endosymbionts have been observed for the gammaproteobacterial symbionts of ves- been vertically transmitted for at least 500 million years. Such icomyid clams that are directly transmitted between host genera- prolonged strict vertical transmission leads to streamlining of sym- tions (13, 14). Such strict vertical transmission leads to substantial biont genomes, and the retained physiological capacities reveal and ongoing genome reduction.
    [Show full text]
  • Morphology of Obligate Ectosymbionts Reveals Paralaxus Gen. Nov., a New
    bioRxiv preprint doi: https://doi.org/10.1101/728105; this version posted August 7, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 Harald Gruber-Vodicka 2 Max Planck Institute for Marine Microbiology, Celsiusstrasse 1; 28359 Bremen, 3 Germany, +49 421 2028 825, [email protected] 4 5 Morphology of obligate ectosymbionts reveals Paralaxus gen. nov., a 6 new circumtropical genus of marine stilbonematine nematodes 7 8 Florian Scharhauser1*, Judith Zimmermann2*, Jörg A. Ott1, Nikolaus Leisch2 and Harald 9 Gruber-Vodicka2 10 11 1Department of Limnology and Bio-Oceanography, University of Vienna, Althanstrasse 12 14, A-1090 Vienna, Austria 2 13 Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, D-28359 Bremen, 14 Germany 15 16 *Contributed equally 17 18 19 20 Keywords: Paralaxus, thiotrophic symbiosis, systematics, ectosymbionts, molecular 21 phylogeny, cytochrome oxidase subunit I, 18S rRNA, 16S rRNA, 22 23 24 Running title: “Ectosymbiont morphology reveals new nematode genus“ 25 Scharhauser et al. 26 27 bioRxiv preprint doi: https://doi.org/10.1101/728105; this version posted August 7, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Scharhauser et al. 2 28 Abstract 29 Stilbonematinae are a subfamily of conspicuous marine nematodes, distinguished by a 30 coat of sulphur-oxidizing bacterial ectosymbionts on their cuticle.
    [Show full text]
  • Lists of Names of Prokaryotic Candidatus Taxa
    NOTIFICATION LIST: CANDIDATUS LIST NO. 1 Oren et al., Int. J. Syst. Evol. Microbiol. DOI 10.1099/ijsem.0.003789 Lists of names of prokaryotic Candidatus taxa Aharon Oren1,*, George M. Garrity2,3, Charles T. Parker3, Maria Chuvochina4 and Martha E. Trujillo5 Abstract We here present annotated lists of names of Candidatus taxa of prokaryotes with ranks between subspecies and class, pro- posed between the mid- 1990s, when the provisional status of Candidatus taxa was first established, and the end of 2018. Where necessary, corrected names are proposed that comply with the current provisions of the International Code of Nomenclature of Prokaryotes and its Orthography appendix. These lists, as well as updated lists of newly published names of Candidatus taxa with additions and corrections to the current lists to be published periodically in the International Journal of Systematic and Evo- lutionary Microbiology, may serve as the basis for the valid publication of the Candidatus names if and when the current propos- als to expand the type material for naming of prokaryotes to also include gene sequences of yet-uncultivated taxa is accepted by the International Committee on Systematics of Prokaryotes. Introduction of the category called Candidatus was first pro- morphology, basis of assignment as Candidatus, habitat, posed by Murray and Schleifer in 1994 [1]. The provisional metabolism and more. However, no such lists have yet been status Candidatus was intended for putative taxa of any rank published in the journal. that could not be described in sufficient details to warrant Currently, the nomenclature of Candidatus taxa is not covered establishment of a novel taxon, usually because of the absence by the rules of the Prokaryotic Code.
    [Show full text]
  • Physiological Homogeneity Among the Endosymbionts of Riftia Pachyptila and Tevnia Jerichonana Revealed by Proteogenomics
    The ISME Journal (2012) 6, 766–776 & 2012 International Society for Microbial Ecology All rights reserved 1751-7362/12 www.nature.com/ismej ORIGINAL ARTICLE Physiological homogeneity among the endosymbionts of Riftia pachyptila and Tevnia jerichonana revealed by proteogenomics Antje Gardebrecht1,2, Stephanie Markert2,3, Stefan M Sievert4, Horst Felbeck5, Andrea Thu¨ rmer6, Dirk Albrecht2,7, Antje Wollherr6, Johannes Kabisch2,3, Nadine Le Bris8,9, Ru¨ diger Lehmann6, Rolf Daniel6, Heiko Liesegang6, Michael Hecker2,3,7 and Thomas Schweder1,2,3 1Department of Pharmaceutical Biotechnology, Ernst-Moritz-Arndt-University, Greifswald, Germany; 2ZIK FunGene, Ernst-Moritz-Arndt-University, Greifswald, Germany; 3Institute of Marine Biotechnology, Greifswald, Germany; 4Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA; 5Marine Biology Research Division, Scripps Institution of Oceanography, San Diego, CA, USA; 6Go¨ttingen Genomics Laboratory, Georg-August-University, Go¨ttingen, Germany; 7Institute for Microbiology, Ernst-Moritz-Arndt-University, Greifswald, Germany; 8Benthic Ecogeochemistry Laboratory, Universite´ Pierre et Marie Curie, Banyuls-sur-Mer, France and 9Laboratoire Environnement Profond, Ifremer, Brest, France The two closely related deep-sea tubeworms Riftia pachyptila and Tevnia jerichonana both rely exclusively on a single species of sulfide-oxidizing endosymbiotic bacteria for their nutrition. They do, however, thrive in markedly different geochemical conditions. A detailed proteogenomic comparison of
    [Show full text]