The symbiotic intestinal ciliates and the evolution of their hosts.
The evolution of sophisticated differentiations of the gastro-intestinal tract enabled herbivorous mammals to digest dietary cellulose and hemicellulose with the aid of a complex anaerobic microbiota. Distinctive symbiotic ciliates, which are unique to this habitat, are the largest representatives of this microbial community. Analyses of a total of 484 different 18S rRNA genes show that extremely complex, but related ciliate communities can occur in the rumen of cattle, sheep, goats and red deer (301 sequences). The communities in the hindgut of equids (Equus caballus, Equus quagga), and elephants (Elephas maximus, Loxodonta africanus; 162 sequences), which are clearly distinct from the ruminant ciliate biota, exhibit a much higher diversity than anticipated on the basis of their morphology. All these ciliates from the gastro-intestinal tract constitute a monophyletic group, which consists of two major taxa, i.e. Vestibuliferida and Entodiniomorphida. The ciliates from the evolutionarily older hindgut fermenters exhibit a clustering that is specific for higher taxa of their hosts, as extant species of horse and zebra on the one hand, and Africa and Indian elephant on the other hand, share related ciliates. The evolutionary younger ruminants altogether share the various entodiniomorphs and the vestibuliferids from ruminants.
Department of Evolutionary Microbiology, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Seung Yeo
SY
Moon-van der Staay
Department of Evolutionary Microbiology, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Georg W M
GW
van der Staay
Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, PL 05-110 Jablonna, Near Warsaw, Poland.
Tadeusz
T
Michalowski
I.N.R.A., Station de Recherches sur la Nutrition des Herbivores, Centre de Recherches de Clermont-Theix, F 63122 St Genès Champanelle, Theix, France.
Jean-Pierre
JP
Jouany
Institute of Animal Physiology, Slovak Academy of Sciences, Soltesovej 4, SK 040 01 Kosice, Slovakia.
Peter
P
Pristas
Institute of Animal Physiology, Slovak Academy of Sciences, Soltesovej 4, SK 040 01 Kosice, Slovakia.
Peter
P
Javorský
Institute of Animal Physiology, Slovak Academy of Sciences, Soltesovej 4, SK 040 01 Kosice, Slovakia.
Svetlana
S
Kišidayová
Institute of Animal Physiology, Slovak Academy of Sciences, Soltesovej 4, SK 040 01 Kosice, Slovakia.
Zora
Z
Varadyova
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK; Institute of Biological Environmental and Rural Science, Aberystwyth University, Ceredigion SY23 3DA, Wales, UK.
Neil R
NR
McEwan
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK; Institute of Biological Environmental and Rural Science, Aberystwyth University, Ceredigion SY23 3DA, Wales, UK.
C Jamie
CJ
Newbold
Department of Evolutionary Microbiology, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Theo
T
van Alen
Department of Evolutionary Microbiology, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Rob
R
de Graaf
Department of Microbial Ecology, Faculty of Life Sciences, University of Vienna, Althanstr. 14, A-1090 Wien, Austria.
Markus
M
Schmid
Centre for Molecular and Biomolecular Informatics, Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein Zuid 26-28, 6525 GA Nijmegen, The Netherlands.
Martijn A
MA
Huynen
Department of Evolutionary Microbiology, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands. Electronic address: jhp.hackstein@gmx.de.
Johannes H P
JH
Hackstein
D000818:Animals; D044822:Biodiversity; D016798:Ciliophora / Q000145:classification* / Q000235:genetics / Q000502:physiology*; D005243:Feces / Q000469:parasitology; D007422:Intestines / Q000469:parasitology*; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012417:Rumen / Q000469:parasitology; D012418:Ruminants / Q000145:classification* / Q000235:genetics / Q000469:parasitology*
D012337:RNA, Ribosomal, 18S
18S rDNA; Caecum/colon; Ciliates; Community analysis; Gastro-intestinal tract; Rumen