Pycnoporus cinnabarinus CIRM-BRFM 50 v1.0
Pycnoporus cinnabarinus. Picture from Mireille Haon, CIRM-CF, INRA-Aix Marseille University, Biotechnology of Filamentous Fungi, Marseilles, France
Pycnoporus cinnabarinus. Picture from Mireille Haon, CIRM-CF, INRA-Aix Marseille University, Biotechnology of Filamentous Fungi, Marseilles, France

The genus Pycnoporus is a cosmopolitan group of white-rot fungi from the order Polyporales, the major group of wood decayers in temperate and tropical forests. As such, Polyporales have a pivotal role in the global carbon cycle; lignocellulose is the principal carbon storage on land, and lignin degradation by white-rot fungi provides access to the polysaccharides that can thereby be used as a source of carbon or energy by other microorganisms. 

Because they are able to totally degrade lignin from wood, white-rot filamentous fungi have a high potential for biotechnological processes, particularly for lignocellulosic feedstock biorefinery applications. Lignocellulose is a high potential renewable resource for the production of biofuels and chemicals, including high-value chemicals, from biomass. Notably, complex raw materials from different origins (dedicated crops, agricultural wastes, silviculture, etc.) that do not compete with food production constitute new sources of sugars that can be fermented for production of bioethanol. 

Pycnoporus emerged in the early 1990s as an extraordinary resource to identify novel enzymes that contribute to efficient biomass degradation or transformation and became a genus of choice for biotechnological applications. Pycnoporus species were first highlighted for their original metabolic pathways involved in the functionalization of plant cell wall aromatic compounds to yield high value molecules, e.g. aromas and antioxidants, and for their potential to produce enzymes of industrial interest, such as hydrolases and oxidases. Oxidases in particular are of large interest for the bioconversion of agricultural by-products and raw plant materials into valuable products, for biopulping and biobleaching of paper pulp and for the biodegradation of organopollutants, xenobiotics and industrial contaminants. One obviously useful feature of the genus Pycnoporus is its ability to overproduce high redox potential laccases — multi-copper extracellular phenoloxidases — as the predominant ligninolytic enzyme.

Pycnoporus is a genus closely related to Trametes, being morphologically similar in all characters except for the conspicuous bright reddish-orange color of the basidiocarp. Pycnoporus cinnabarinus is one of the four representative species of the genus. Pycnoporus cinnabarinus is a cosmopolitan species from the North Temperate Zone and is common in Europe. This saprophytic fungus grows during summer and autumn on the trunk of fallen trees and stumps of broad-leaved trees. It is rarely found on conifers. Pycnoporus cinnabarinus has been shown as laccase producer with high redox potential. The genome sequencing for Pycnoporus cinnabarinus will allow exploration for enzymes with original properties for biomass conversion processes. The sequence information will enable a comparison with other white-rotters, and will deepen our understanding of the functional diversity among Polyporales, i.e. enzymatic capabilities linked to plant cell wall modifications.