| Abstract |
Plant terpenoids compose a natural source of chemodiversity of exceptional value. Many
of these compounds own biological/pharmacological activity, others are regarded as
unique chemical skeletons for the synthesis of derivatives with improved properties.
Functional chemical modification of terpenoids through biotransformation frequently
relies on the use of Ascomycota strains, but information on major cellular responses
is still largely lacking. Penicillium janczewskii mediates a stereo-selective hydroxylation
of labdanolic acid (LA)—terpenoid found abundantly in Cistus ladanifer—producing
3?-hydroxy-labdanolic acid with yields >90%. Herein, combined analyses of mycelial
and extracellular differential proteomes demonstrated that the plant terpenoid increased
stress responses, especially against oxidative stress (e.g., accumulation of superoxide
dismutase) and apparently altered mitochondria functioning. One putative cytochrome
P450 monooxygenase differentially accumulated in the secretome and the terpenoid
bioconversion was inhibited in vivo in the presence of a P450 inhibitor. The stereoselective
hydroxylation of the plant terpenoid is likely mediated by P450 enzymes, yet its
unequivocal identity remains unclear. To the best of our knowledge, this is the first time
that proteomics was used to investigate how a plant terpenoid impacts the metabolism
of a filamentous fungus during its efficiently biotransformation. Our findings may encourage
the development of new strategies for the valorization of plant natural resources
through biotechnology. |
