Open AccessInduction of lcc 2 expression and activity by A garicus bisporus provides defence against T richoderma aggressivum toxic extracts
Author(s) -
Sjaarda Calvin P.,
Abubaker Kamal S.,
Castle Alan J.
Publication year - 2015
Publication title -
microbial biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.287
H-Index - 74
ISSN - 1751-7915
DOI - 10.1111/1751-7915.12277
Subject(s) - laccase , agaricus bisporus , biology , strain (injury) , microbiology and biotechnology , gene , enzyme , biochemistry , food science , mushroom , anatomy
Summary Laccases are used by fungi for several functions including defence responses to stresses associated with attack by other fungi. Laccase activity changes and the induction of two laccase genes, lcc 1 and lcc 2, in A garicus bisporus were measured in response to toxic extracts of medium in which T richoderma aggressivum , the cause of green mould disease, was grown. A strain of A . bisporus that shows resistance to the extracts showed higher basal levels and greater enzymatic activity after extract exposure than did a sensitive strain. Furthermore, pre‐incubation of T . aggressivum extract with laccases reduced toxicity. Faster induction and greater numbers of lcc 2 transcripts in response to the extract were noted in the resistant strain than in the sensitive strain. The timing and increase in lcc2 transcript abundance mirrored changes in total laccase activity. No correlation between resistance and lcc 1 transcription was apparent. Transcript abundance in transformants with a siRNA construct homologous to both genes varied widely. A strong negative correlation between transcript abundance and sensitivity of the transformant to toxic extract was observed in plate assays. These results indicated that laccase activity and in particular that encoded by lcc 2 contributes to toxin metabolism and by extension green mould disease resistance.