Pycnoporus

Figure 17.7 Electrocatalysis of O2 reduction by Pycnoporus cinnabarinus laccase on a 2-aminoanthracene-modified pyrolytic graphite edge (PGE) electrode and an unmodified PGE electrode at 25 °C in sodium citrate buffer (200 mM, pH 4). Red curves were recorded immediately after spotting laccase solution onto the electrode, while black curves were recorded after exchanging the electrochemical cell solution for enzyme-fiiee buffer solution. Insets show the long-term percentage change in limiting current (at 0.44 V vs. SHE) for electrocatalytic O2 reduction by laccase on an unmodified PGE electrode ( ) or a 2-aminoanthracene modified electrode ( ) after storage at 4 °C, and a cartoon representation of the probable route for electron transfer through the anthracene (shown in blue) to the blue Cu center of laccase. Reproduced by permission of The Royal Society of Chemistry fi om Blanford et al., 2007. (See color insert.)...

Schliephake K, Mainwaring DE, Lonergan GT, Jones KI, Baker WL (2000) Transformation and degradation of the disazo dye Chicago sky blue by a purified laccase from Pycnoporus cinnabarinus. Enzyme Microb Biotechnol 27 100-107... 

In Phanerochaete flavido-alba, an induction of ligninolytic activities that was ascribed to phenolic compounds was evidenced [69]. Phenols have also been shown to have an important role as redox mediators for dye degradation with laccases from Pycnoporus cinnabarinus and Trametes villosa, and they resulted to be necessary to degrade a strongly recalcitrant azo dye, the Reactive Black 5 [70]. 

Pycnoporus sanguineus (DPF 44) Corsican pine (Pinus nigra) 17 40 Forster eta/. (1997)... 

Ichishima, E., Ito, Y., and Takeuchi, M. (1985). 1,2-a-D-mannosidase from a wood-rotting Basidiomycete, Pycnoporus sanguineus. Phytochemistry, 24, 2835-2837. 

At least 87 basidiomycete heme peroxidases have been described to date, whose evolutionary relationships are shown in Fig. 3.3. It also includes putative peroxidases from the genomes of Phanerochaete chrysosporium, Pleurotus ostreatus. and Pycnoporus cinnabarinus, and two reference ascomycete peroxidases. 

Vanillin Ferulic acid,eugenol, isoeugenol Corynebacterium glutamicum, Pycnoporus cinnabar-inus, Serratia species,Kleb-sella species, Enterobacter species. Pseudomonas species, Aspergillus niger Vanilla... 

Bonnin, E. et al., Aspergillus niger 1-1472 and Pycnoporus cinnabarinus MUCEL 39533, selected for the biotransformation of ferulic acid to vanillin, are also able to produce cell wall polysaccharide-degrading enzymes and feruloyl esterases, Enzyme Microb. Technol, 28, 70, 2001. 

C Eggert, U Temp, KEL Eriksson. Laccase is essential for lignin degradation by the white-rot fungus Pycnoporus cinnabarinus. FEBS Lew 407(1 ) 89-92, 1997. 

K Li, PS Horanyi, R Collins, RS Phihips, K-EL Eriksson. Investigation of the role of 3-hydroxyanthranilic acid in the degradation of lignin by white-rot fungus Pycnoporus cinnabarinus. Enzyme Microb. Technol. 28(4—5) 301-307, 2001. 

Kobayashi and coworkers reported on the mediator-free direct polymerization of acryl amide using the laccase from Pycnoporus coccineus suggesting a simplified polymerization scheme [67]. Using the laccase from Myceliophthora ther-mophilia, this was not achieved [68,69] and a follow-up study validating Kobayashi s initial study is still awaited. 

Also in the polyporaceous fungus, Pycnoporus cinnabarinus, the conversion of HA to CA has been shown, even if there is no Mn2+ requirement for the process [194]. The same was seen also in extracts of spinach leaves [195]. Nuclear fractions, coming from other rat organs, were found able to catalyse the conversion of HA to CA [195], Nucleotide bases, and in particular guanine, behave as competitive inhibitors for the conversion, and this fact, together with the strict structural analogies between... 

As a concluding remark, it can be noted here that the presence of HA as the redox mediator could be of taxonomic value, helping to disentangle the complex classification of the genus Pycnoporus and of some others strictly related to it. 

Sigoillot, C., Lomascolo, A., Record, E., Robert, J. L., Asther, M., Sigoillot, J. C. (2002). Lignoeellulolytic and hemicellulolytic system of Pycnoporus cinnabarinus isolation and characterization of a cellobiose dehydrogenase and a new xylanase. Enzyme and Microbial Technology, 31, 876-883. 

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