Journal Article
Eukaryotic Cell, vol. 12, iss. 11, pp. 1499-1508, 2013
Authors
Lea Atanasova, Benjamin P. Knox, Christian P. Kubicek, Irina S. Druzhinina, Scott E. Baker
Abstract
ABSTRACT
Species of the fungal genus
Trichoderma
(Hypocreales, Ascomycota) are well-known for their production of various secondary metabolites. Nonribosomal peptides and polyketides represent a major portion of these products. In a recent phylogenomic investigation of
Trichoderma
polyketide synthase (PKS)-encoding genes, the
pks4
from
T. reesei
was shown to be an orthologue of pigment-forming PKSs involved in synthesis of aurofusarin and bikaverin in
Fusarium
spp. In this study, we show that deletion of this gene in
T. reesei
results in loss of green conidial pigmentation and in pigmentation alteration of teleomorph structures. It also has an impact on conidial cell wall stability and the antagonistic abilities of
T. reesei
against other fungi, including formation of inhibitory metabolites. In addition, deletion of
pks4
significantly influences the expression of other PKS-encoding genes of
T. reesei
. To our knowledge, this is the first indication that a low-molecular-weight pigment-forming PKS is involved in defense, mechanical stability, and stress resistance in fungi.
