The Effects of Fungal Peroxidase on Na-Lignosulfonates

Lignin Peroxidase Activity Is Not Important in Biological Bleaching and Delignification of Unbleached Kraft Pulp by Trametes versicolor

“…(x) Earlier work demonstrated that in our system, direct contact between pulp fibers and the hyphae of T. versicolor is not necessary for biobleaching, indicating that the agents of delignification, if not lignin degradation, are soluble (2), yet analysis of the liquor showed no LP. No single one of the above facts is a sufficient basis on which to reject secreted LP as an important biobleaching component in the T. versicolor system, but taken together they seem to be conclusive. This of course does not preclude a role for intracellular peroxidases of the type extensively investigated by Lobarzewski et al (32)(33)(34), although these proteins could not be central to cell-free biobleaching. These results also neither support nor deny a role for MnPs or Mn3+ chelates produced indirectly by laccase (3).…”

Wood production, wood technology, and biotechnological impacts

“…Heme-containing, H 2 O 2 -depending enzymes with properties similar to horseradish and other plant peroxidases have been described from the white-rots Inonotus radiatus and related species, Pholiota mutabilis and relatives, and T. versicolor where they are believed to contribute to lignin degradation. Such plant-like manganeseindependent peroxidases from T. versicolor can polymerise and depolymerise lignin similar to LiP and MnP but do not react with veratryl alcohol (Lobarzewski et al 1982, Lobarzewski 1990, Stoychev et al 1998. Horseradish peroxidase similar enzymes are also present in saprophytic fungi, e.g.…”

Production and properties of an extracellular peroxidase from Coriolus versicolor which catalyses Cα-Cβ cleavage in a lignin model compound

“…The physiological requirements for ligninolytic activity in cultures of C. versicolor are similar to those described for cultures of P. chrysosporium from which proteins with peroxidase-type activity have been identified [1,2,[8][9][10]. Extracellular peroxidases have been iso-lated from C. versicolor, one of which was shown to bind cyanide and hydrogen peroxide [11] and reduce the molecular weight of Na-lignosulphonates [12], while another was identified as a 'peroxidase-type' haem protein of 53.7 kDa [13]. However, none of these proteins was characterised as a lignin-degrading peroxidase of the type described from P. chrysosporium, or shown to be capable of forming radical cations in aromatic substrates, a characteristic of lignin degradation [14].…”