Linear versus circular mitochondrial genomes: intraspecies variability of mitochondrial genome architecture in Candida parapsilosis.
The yeast species Candida parapsilosis, an opportunistic pathogen, exhibits genetic and genomic heterogeneity. To assess the polymorphism at the level of mitochondrial DNA (mtDNA), the organization of the mitochondrial genome in strains belonging to the three variant groups of this species was investigated. Although these analyses revealed a group-specific restriction fragment pattern of mtDNA, strains belonging to different groups appear to have similar genes in the same gene order. An extensive survey of C. parapsilosis isolates uncovered surprising alterations in the molecular architecture of their mitochondrial genome. A screening strategy for strains harbouring mtDNA with rearranged architecture showed that nearly all strains from groups I and III possess linear mtDNA molecules terminating with arrays of tandem repeat units, while most of the group II strains have a circular mitochondrial genome. In addition, it was found that linear genophores in mitochondria of strains from different groups differ in the sequence of the mitochondrial telomeric repeat unit. The occurrence of altered forms of mtDNA among C. parapsilosis strains opens up the unique possibility to address questions concerning the evolutionary origin and replication strategy of linear and circular genomes in mitochondria.
Rycovska
Adriana
A
Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-1, 842 15 Bratislava, Slovak Republic.
Valach
Matus
M
Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-1, 842 15 Bratislava, Slovak Republic.
Tomaska
Lubomir
L
Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-1, 842 15 Bratislava, Slovak Republic.
Bolotin-Fukuhara
Monique
M
Institute of Genetics and Microbiology, University of Paris XI, 91 405 Orsay, France.
Nosek
Jozef
J
Institute of Genetics and Microbiology, University of Paris XI, 91 405 Orsay, France.|Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina CH-1, 842 15 Bratislava, Slovak Republic.
D002175:Candida / Q000145:classification / Q000235:genetics*; D004270:DNA, Circular / Q000235:genetics*; D004271:DNA, Fungal / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D014644:Genetic Variation; D016681:Genome, Fungal; D008928:Mitochondria; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D016615:Telomere / Q000235:genetics
D004270:DNA, Circular; D004271:DNA, Fungal; D004272:DNA, Mitochondrial