Advertisement

Antonie van Leeuwenhoek

, Volume 64, Issue 3–4, pp 261–271 | Cite as

Systematic and morphological diversity of endosymbiotic methanogens in anaerobic ciliates

  • T. Martin Embley
  • Bland J. Finlay
Article

Abstract

The identities and taxonomic diversity of the endosymbiotic methanogens from the anaerobic protozoaMetopus contortus, Metopus striatus, Metopus palaeformis, Trimyema sp. andPelomyxa palustris were determined by comparative analysis of their 16S ribosomal RNA sequences. Fluorescent oligonucleotide probes were designed to bind to the symbiont rRNA sequences and to provide direct visual evidence of their origins from methanogenic archaea contained within the host cells. Confocal microscopy was used to analyze the morphology of the endosymbionts in whole cells ofMetopus palaeformis, Metopus contortus, Trimyema sp. andCyclidium porcatum. The endosymbionts are taxonomically diverse and are drawn from three different genera;Methanobacterium, Methanocorpusculum andMethanoplanus. In every case the symbionts are closely related to, but different from, free-living methanogens for which sequences are available. It is thus apparent that symbioses have been formed repeatedly and independently. Ciliates which are unrelated to each other (Trimyema sp. andMetopus contortus) may contain symbionts which are closely related, and congeneric ciliates (Metopus palaeformis andM. contortus) may contain symbionts which are distantly related to each other. This suggests that some of the symbiotic associations must be relatively recent. For example, at least one of the symbioses inMetopus must postdate the speciation ofM. palaeformis andM. contortus. Despite this,Metopus contortus, Trimyema sp., Cyclidium porcatum and their respective endosymbionts show sophisticated morphological interactions which probably facilitate the exchange of materials between the partners.

Key words

endosymbionts anaerobic protozoa methanogens 16S rRNA coadaptation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Achenbach-Richter L, Gupta R, Zillig, W & Woese, CR (1988) Rooting the archaebacterial tree: the pivotal role ofThermococcus celer in archaebacterial evolution. System. Appl. Microbiol. 14: 231–240Google Scholar
  2. Boone DR & Mah RA (1989)Methanobacteriaceae. In: Staley JT, Bryant MP, Pfennig N & Holt, JG (Ed) Bergey's Manual of Systematic Bacteriology (pp.2175–2178). Williams and Wilkins, BaltimoreGoogle Scholar
  3. Burggraf S, Stetter KO, Rouviere P & Woese CR (1991) Methanopyrus kandleri: an archaeal methanogen unrelated to all other known methanogens. System. Appl. Microbiol. 14: 346–351Google Scholar
  4. Corliss JO (1979) The Ciliated Protozoa. Pergamon Press, OxfordGoogle Scholar
  5. DeLong EF, Wickham GS & Pace NR (1989) Phylogenetic stains: ribosomal RNA based probes for the identification of single cells. Science 243: 1360–1363Google Scholar
  6. Embley TM (1991) The linear PCR reaction: a simple and robust method for sequencing amplified rRNA genes. Lett. Appl. Microbiol. 13: 171–174Google Scholar
  7. Embley TM, Finlay BJ & Dyal P (1992a) The use of rRNA sequences and fluorescent probes to investigate the phylogenetic position of the anaerobic ciliateMetopus palaeformis and its archaeobacterial symbiont. J. Gen. Microbiol. 138: 1479–1487Google Scholar
  8. Embley TM, Finlay BJ & Brown S (1992b) RNA sequence analysis shows that the symbionts in the ciliateMetopus contortus are polymorphs of a single methanogen species. FEMS Microbiol. Lett. 97: 57–62Google Scholar
  9. Esteban G, Guhl BE, Clarke KJ, Finlay BJ & Embley TM (1993)Cyclidium porcatum n.sp.: a free-living anaerobic scuticociliate containing a stable complex of hydrogenosomes, eubacteria and archaeobacteria. Europ J Protistol (in press)Google Scholar
  10. Fenchel T (1993) Methanogenesis in marine shallow water sediments: the quantitative role of anaerobic protozoa with endosymbiotic methanogenic bacteria. Ophelia 37: 67–82.Google Scholar
  11. Fenchel T & Finlay BJ (1990) Anaerobic free-living protozoa: growth efficiencies and the structure of anaerobic communities. FEMS Microbiol. Ecol. 74: 269–276Google Scholar
  12. Fenchel T & Finlay BJ (1991) Endosymbiotic methanogenic bacteria in anaerobic ciliates: significance for the growth efficiency of the host. J. Protozool. 38: 18–22Google Scholar
  13. Fenchel T & Finlay BJ (1992) Production of methane and hydrogen by anaerobic ciliates containing symbiotic methanogens. Arch. Microbiol. 157: 475–480Google Scholar
  14. Finlay BJ & Fenchel T (1989) Hydrogenosomes in some anaerobic ciliates resemble mitochondria. FEMS Microbiol. Lett. 65: 311–314Google Scholar
  15. Finlay BJ & Fenchel T (1991a) An anaerobic protozoon, with symbiotic methanogens, living in municipal landfill material. FEMS Microbiol. Ecol. 85: 169–180Google Scholar
  16. Finlay BJ & Fenchel T (1991b) Polymorphic bacterial symbionts in the anaerobic ciliated protozoonMetopus contortus. FEMS Microbiol. Lett. 79: 187–190Google Scholar
  17. Finlay BJ & Fenchel T (1992a) An anaerobic ciliate as a natural chemostat for the growth of endosymbiotic methanogens. Europ. J. Protistol. 28: 127–137Google Scholar
  18. Finlay BJ & Fenchel T (1992b) Methanogens and other bacteria as symbionts of free-living anaerobic ciliates. Symbiosis 14: 375–390.Google Scholar
  19. Finlay BJ, Embley TM & Fenchel T (1993) A new polymorphic methanogen, closely related toMethanocorpusculum parvum, living in stable symbiosis within the anaerobic ciliateTrimyema sp. J. Gen. Microbiol. 139: 371–378Google Scholar
  20. Jones WJ, Nagle DP & Whitman WB (1987) Methanogens and the diversity of archaebacteria. Microbiol. Rev. 51: 135–177Google Scholar
  21. Jukes TH & Cantor CR (1969) Evolution of protein molecules. In: Munro, HN (Ed) Mammalian Protein Metabolism (pp 21–132). Academic Press, New YorkGoogle Scholar
  22. Holler S & Pfennig N (1991) Fermentation products of the anaerobic ciliateTrimyema compressum in monoxenic cultures. Arch. Microbiol. 156: 327–334Google Scholar
  23. Lechner K, Wich G & Bock A (1985) The nucleotide sequence of the 16s rRNA gene and flanking regions fromMethanobacterium formicium: on the phylogenetic relationship between methanogenic and halophilic archaebacteria. System. Appl. Microbiol. 6: 157–163Google Scholar
  24. Muller M (1988). Energy metabolism of protozoa without mitochondria. Ann. Rev. Microbiol. 42: 465–488Google Scholar
  25. Neefs J-M, Van de Peer Y, De Rijk P, Goris A & De Wachter R (1991). Compilation of small ribosomal subunit RNA sequences. Nucl. Acid. Res. Supplement 19: 1987–2015Google Scholar
  26. Olsen GJ, Larson N & Woese CR (1991) The ribosomal RNA data base project. Nucl. Acid. Res. Supplement 19: 2017–2021Google Scholar
  27. Rouviere P, Mandelco L, Winker S & Woese CR (1992) A detailed phylogeny of theMethanomicrobiales. System. Appl. Microbiol. 15: 363–371Google Scholar
  28. Saiki RK, Gelfand DH, Stoffel S, Scharf SJ, Higuchi R, Horn GT, Mullis KB & Erlich HA (1988) Primer-directed enzymatic amplification of DNA with a thermostable DNA polymerase. Science 239: 487–491Google Scholar
  29. Saitou N & Nei M (1987) The neighbour joining method: a new method for constructing phylogenetic trees. Mol. Biol. Evol. 4: 406–425Google Scholar
  30. Stahl DA & Amman RI (1991) Development and application of nucleic acid probes in bacterial systematics. In: Stackebrandt E & Goodfellow M (Ed) Nucleic Acid Techniques in Bacterial Systematics (pp. 205–248), John Wiley: ChichesterGoogle Scholar
  31. van Bruggen JJA, Stumm CK & Vogels GD (1983) Symbiosis of methanogenic bacteria and sapropelic protozoa. Arch. Microbiol. 136: 89–95Google Scholar
  32. van Bruggen JJA, Zwart KB, van Assema RM, Stumm CK & Vogels GD (1984)Methanobacterium formicium, an endosymbiont of the anaerobic ciliateMetopus striatus McMurrich. Arch. Microbiol. 139: 1–7Google Scholar
  33. van Bruggen JJA, Zwart KB, Hermans JGF, van Hove EM, Stumm CK & Vogels GD (1986) Isolation and characterisation ofMethanoplanus endosymbiosus sp. nov. an endosymbiont of the marine sapropelic ciliateMetopus contortus Quennerstedt. Arch. Microbiol. 144: 367–374Google Scholar
  34. Wagener S, Bardele CF & Pfennig N (1990) Functional integration ofMethanobacterium formicicum into the anaerobic ciliateTrimyema compressum. Arch. Microbiol. 153: 496–501Google Scholar
  35. Woese CR (1987) Bacterial evolution. Microbiol. Rev. 51: 221–271Google Scholar
  36. Yang DC, Kaine BP & Woese CR (1985) The phylogeny of archaebacteria. System. Appl. Microbiol. 6: 251–256Google Scholar

Copyright information

© Kluwer Academic Publishers 1993

Authors and Affiliations

  • T. Martin Embley
    • 1
  • Bland J. Finlay
    • 2
  1. 1.Microbiology GroupThe Natural History MuseumLondonUK
  2. 2.Windermere Laboratory, Far SawreyInstitute of Freshwater EcologyAmblesideUK

Personalised recommendations