Isolation and characterization of homokaryotic strains from the ligninolytic basidiomycete Ceriporiopsis subvermispora

Genetic analyses of the lignin-degrading fungus Ceriporiopsis subvermispora is complicated by a dikaryotic nuclear condition and the absence of sport: forms. Previous investigations had identified a family of closely related sequences encoding manganese peroxidase (MnP), but the relationship between genes and allelic variants could not be experimentally established. Addres sing this issue, homokaryotic derivatives of C. subvermipora strain FP10575 2 were isolated from regenerated protoplasts. Designated CsA and CsB. their homokaryotic nature was established by polymerase chain reaction amplifica tion and sequence analysis of the allelic variants of three MnP genes. Isoe lectrofocusing revealed fewer MnP isoenzymes in filtrates of homokaryon cul tures relative to the parental strain. The homokaryotic strains will simpli fy genetic analyses, particularly the identification of neu genes. (C) 2001 Federation of European Microbiological Societies. published by Elsevier Sc ience B.V. All rights reserved.