title: Genome sequence of the stramenopile Blastocystis, a human anaerobic parasite.
abstract: BACKGROUND
  Blastocystis is a highly prevalent anaerobic eukaryotic parasite of humans and animals that is associated with various gastrointestinal and extraintestinal disorders. Epidemiological studies have identified different subtypes but no one subtype has been definitively correlated with disease.
  
  
  RESULTS
  Here we report the 18.8 Mb genome sequence of a Blastocystis subtype 7 isolate, which is the smallest stramenopile genome sequenced to date. The genome is highly compact and contains intriguing rearrangements. Comparisons with other available stramenopile genomes (plant pathogenic oomycete and diatom genomes) revealed effector proteins potentially involved in the adaptation to the intestinal environment, which were likely acquired via horizontal gene transfer. Moreover, Blastocystis living in anaerobic conditions harbors mitochondria-like organelles. An incomplete oxidative phosphorylation chain, a partial Krebs cycle, amino acid and fatty acid metabolisms and an iron-sulfur cluster assembly are all predicted to occur in these organelles. Predicted secretory proteins possess putative activities that may alter host physiology, such as proteases, protease-inhibitors, immunophilins and glycosyltransferases. This parasite also possesses the enzymatic machinery to tolerate oxidative bursts resulting from its own metabolism or induced by the host immune system.
  
  
  CONCLUSIONS
  This study provides insights into the genome architecture of this unusual stramenopile. It also proposes candidate genes with which to study the physiopathology of this parasite and thus may lead to further investigations into Blastocystis-host interactions.
authors: Genoscope (CEA) and CNRS UMR 8030, Université d'Evry, 2 rue Gaston Crémieux, 91057 Evry, France.
authors: France
authors: F
authors: Denoeud
authors: Michaël
authors: M
authors: Roussel
authors: Benjamin
authors: B
authors: Noel
authors: Ivan
authors: I
authors: Wawrzyniak
authors: Corinne
authors: C
authors: Da Silva
authors: Marie
authors: M
authors: Diogon
authors: Eric
authors: E
authors: Viscogliosi
authors: Céline
authors: C
authors: Brochier-Armanet
authors: Arnaud
authors: A
authors: Couloux
authors: Julie
authors: J
authors: Poulain
authors: Béatrice
authors: B
authors: Segurens
authors: Véronique
authors: V
authors: Anthouard
authors: Catherine
authors: C
authors: Texier
authors: Nicolas
authors: N
authors: Blot
authors: Philippe
authors: P
authors: Poirier
authors: Geok Choo
authors: GC
authors: Ng
authors: Kevin S W
authors: KS
authors: Tan
authors: François
authors: F
authors: Artiguenave
authors: Olivier
authors: O
authors: Jaillon
authors: Jean-Marc
authors: JM
authors: Aury
authors: Frédéric
authors: F
authors: Delbac
authors: Patrick
authors: P
authors: Wincker
authors: Christian P
authors: CP
authors: Vivarès
authors: Hicham
authors: H
authors: El Alaoui
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001483:Base Sequence; D016844:Blastocystis / Q000235:genetics* / Q000378:metabolism; D018432:Drug Resistance, Multiple / Q000235:genetics; D022761:Gene Transfer, Horizontal; D018503:Genome, Protozoan; D054884:Host-Pathogen Interactions; D006801:Humans; D053858:Metabolic Networks and Pathways; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D020543:Proteome; D058009:Stramenopiles / Q000235:genetics* / Q000378:metabolism; D013559:Symbiosis / Q000235:genetics; D037521:Virulence Factors
chemical_list: D000975:Antioxidants; D020543:Proteome; D037521:Virulence Factors