Visualization of the action of ligninolytic enzymes on high yield pulp fibers

High-yield pulps from wheat straw and from poplar wood were treated with manganese-peroxidase (MnP) or with laccase (Lac), before and after a second refining stage

The genome of the white-rot fungus Pycnoporus cinnabarinus : a basidiomycete model with a versatile arsenal for lignocellulosic biomass breakdown

Background: Saprophytic filamentous fungi are ubiquitous micro-organisms that play an essential role in photosynthetic carbon recycling. The wood-decayer Pycnoporus cinnabarinus is a model fungus for the study of plant cell wall decomposition and is used for a number of applications in green and white biotechnology.Results: The 33.6 megabase genome of P. cinnabarinus was sequenced and assembled, and the 10,442predicted genes were functionally annotated using a phylogenomic procedure. In-depth analyses were carried out for the numerous enzyme families involved in lignocellulosic biomass breakdown, for protein secretion and glycosylation pathways, and for mating type. The P. cinnabarinus genome sequence revealed a consistent repertoire of genes shared with wood-decaying basidiomycetes. P. cinnabarinus is thus fully equipped with the classical families involved in cellulose and hemicellulose degradation, whereas its pectinolytic repertoire appears relatively limited. In addition, P. cinnabarinus possesses a complete versatile enzymatic arsenal for lignin breakdown. We identified several genes encoding members of the three ligninolytic peroxidase types, namely lignin peroxidase, manganese peroxidase and versatile peroxidase. Comparative genome analyses were performed in fungi displaying different nutritional strategies (white-rot and brown-rot modes of decay). P. cinnabarinus presents a typical distribution of all thespecific families found in the white-rot life style. Growth profiling of P. cinnabarinus was performed on 35 carbon sources including simple and complex substrates to study substrate utilization and preferences. P. cinnabarinus grew faster on crude plant substrates than on pure, mono- or polysaccharide substrates. Finally, proteomic analyses were conducted from liquid and solid-state fermentation to analyze the composition of the secretomes corresponding to growth on different substrates. The distribution of lignocellulolytic enzymes in the secretomes was strongly dependent on growth conditions, especially for lytic polysaccharide mono-oxygenases.Conclusions: With its available genome sequence, P. cinnabarinus is now an outstanding model system for the study of the enzyme machinery involved in the degradation or transformation of lignocellulosic biomass.Microbial Biotechnolog

Les arbres malades de la mer

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Lignocellulolytic and hemicellulolytic system of Pycnoporus cinnabarinus: isolation and characterization of a cellobiose dehydrogenase and a new xylanase

International audienc

Design and scale up of a process for manganese peroxidase production using the hypersecretory strain Phanerochaete chrysosporium I-1512

International audienc

Enhancing phenanthrene biomineralization in a polluted soil using gaseous toluene as a cosubstrate

International audienc

Enhancing phenanthrene biomineralization in a polluted soil using gaseous toluene as a cosubstrate

International audienc

Comparison of static and agitated immobilized cultures of Phanerochaete chrysosporium for the degradation of pentachlorophenol and its metabolite pentachloroanisole

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Selection of Pycnoporus cinnabarinus strains for laccase production

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Biotransformation of benzo(a)pyrene in bench scale reactor using laccase of Pycnoporus cinnabarinus

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