A mitochondrial respiratory mutant of Podospora anserina obtained by short-term submerged cultivation of senescent mycelium

Abstract

A spontaneous long-lived isolate of Podospora anserina obtained by relatively short-term submerged cultivation of the wild-type senescent culture and conventionally termed “immortal” was shown to be a cox1 mutant. As a respiratory mutant, the isolate in question is characterized by dysfunction of the cytochrome respiratory chain, activation of alternative respiration leading to a low level of reactive oxygen species production, and the lack of accumulation of α-senDNA, the specific factor of P. anserina senescence. Absence of visible vegetative incompatibility was shown in the fungal mutants carrying respiratory defects. It was discovered that the P. anserina female sex organs could be fertilized not only by microconidia but also by the fragments of vegetative mycelium. Partial nonobservance of monoparental female inheritance of mitochondria associated with fertilization by vegetative mycelium was also revealed.