Analysis of Two Genomes from the Mitochondrion-Like Organelle of the Intestinal Parasite Blastocystis: Complete Sequences, Gene Content, and Genome Organization
Open Access
- 21 August 2008
- journal article
- research article
- Published by Oxford University Press (OUP) in Molecular Biology and Evolution
- Vol. 25 (11), 2475-2482
- https://doi.org/10.1093/molbev/msn193
Abstract
Acquisition of mitochondria by the ancestor of all living eukaryotes represented a crucial milestone in the evolution of the eukaryotic cell. Nevertheless, a number of anaerobic unicellular eukaryotes have secondarily discarded certain mitochondrial features, leading to modified organelles such as hydrogenosomes and mitosomes via degenerative evolution. These mitochondrion-derived organelles have lost many of the typical characteristics of aerobic mitochondria, including certain metabolic pathways, morphological traits, and, in most cases, the organellar genome. So far, the evolutionary pathway leading from aerobic mitochondria to anaerobic degenerate organelles has remained unclear due to the lack of examples representing intermediate stages. The human parasitic stramenopile Blastocystis is a rare example of an anaerobic eukaryote with organelles that have retained some mitochondrial characteristics, including a genome, whereas they lack others, such as cytochromes. Here we report the sequence and comparative analysis of the organellar genome from two different Blastocystis isolates as well as a comparison to other genomes from stramenopile mitochondria. Analysis of the characteristics displayed by the unique Blastocystis organelle genome gives us an insight into the initial evolutionary steps that may have led from mitochondria to hydrogenosomes and mitosomes.Keywords
This publication has 45 references indexed in Scilit:
- Localization and nucleotide specificity ofBlastocystissuccinyl-CoA synthetaseMolecular Microbiology, 2008
- Organelles in Blastocystis that Blur the Distinction between Mitochondria and HydrogenosomesCurrent Biology, 2008
- Draft Genome Sequence of the Sexually Transmitted Pathogen Trichomonas vaginalisScience, 2007
- The New Higher Level Classification of Eukaryotes with Emphasis on the Taxonomy of ProtistsThe Journal of Eukaryotic Microbiology, 2005
- An anaerobic mitochondrion that produces hydrogenNature, 2005
- ProtTest: selection of best-fit models of protein evolutionBioinformatics, 2005
- MUSCLE: multiple sequence alignment with high accuracy and high throughputNucleic Acids Research, 2004
- Gapped BLAST and PSI-BLAST: a new generation of protein database search programsNucleic Acids Research, 1997
- tRNAscan-SE: A Program for Improved Detection of Transfer RNA Genes in Genomic SequenceNucleic Acids Research, 1997
- The Mitochondrial LSU rDNA of the Brown AlgaPylaiella littoralisReveals α-Proteobacterial Features and is Split by Four Group IIB Introns with an Atypical PhylogenyJournal of Molecular Biology, 1995