Characterization of a Novel Manganese Peroxidase-Lignin Peroxidase Hybrid Isozyme Produced by Bjerkandera Species Strain BOS55 in the Absence of Manganese

Abstract

A novel manganese-dependent peroxidase (MnP) isozyme produced in manganese-free cultures of Bjerkandera sp. strain BOS55 was purified and characterized. The production of the enzyme was greatly stimulated by the exogenous addition of various physiological organic acids such as glycolate, glyoxylate, and oxalate.

Molecular characterisation of a versatile peroxidase from a Bjerkandera strain

“…MnP isoenzymes, purified from P. ostreatus and duly characterised by Giardina et al (2000), are able to oxidise phenolic substrates both in the presence and absence of manganese, as already reported (Giardina et al, 2000;Heinfling et al, 1998b;Mester and Field, 1998) for isozymes produced by other strains of P. ostreatus, P. pulmonarius, P. eryngii, B. adusta and Bjerkandera sp.…”

“…A novel class of ligninolytic peroxidases, named versatile peroxidases, with high affinity for manganese and dyes, has been described; these enzymes can also oxidise 2,6-dimethoxyphenol (DMP) and veratryl alcohol (VA) in a manganese-independent reaction (Camarero et al, 1996(Camarero et al, , 1999(Camarero et al, , 2000Giardina et al, 2000;Heinfling et al, 1998a,b,c;Martinez, 2002;Mester and Field, 1998;Palma et al, 2000;Ruiz-Duenas et al, 1999b. Until now, however, those enzymes have only been isolated from Pleurotus ostreatus, Pleurotus eryngii, Pleurotus pulmonarius, Bjerkandera adusta and Bjerkandera sp.…”

Wood production, wood technology, and biotechnological impacts

“…Next to typical MnP, variations of this enzyme were found in fungi of the genera Pleurotus (Martínez et al 1996, Böckle et al 1998, Heinfling et al 1998b, Camarero et al 1999 and Bjerkandera (Heinfling et al 1998a, Mester & Field 1998, Rodakiewicz-Nowak et al 2006 which do not require a Mn 2+ ion and can act directly on organic substrates such as veratryl alcohol, p-dimethoxybenzene, hydrochinones, and substituted phenols. In addition, they are able to oxidise Mn 2+ to Mn 3+ , thus combining partially functions of MnP and of LiP.…”

Insights into the Mechanism of Lignocellulose Degradation by Versatile Peroxidases

“…wood and the soil, host good quantity of manganese which is oxidized by versatile peroxidase; this oxidized manganese chelates with organic acid secreted by fungi such as glyoxalate, oxalate, lactate to act as a diffusible oxidant in oxidation of phenolic lignin structures and also non-phenolic moieties through formation of lipid peroxyl radicals 15 . Organic acids are secreted by fungi through de novo synthesis and also during degradation of lignin 16 . However, high redox potential substrate oxidation by versatile peroxidases is inhibited by Mn 2+ with decrease in rate of the former reaction, a reaction supposed to be non-competitive inhibition 17 .…”

“…These fungi have evolved with the ability to efficiently degrade whole wood components by selective or simultaneous delignification with selective delignification more pronounced for their action focused on lignin with least attack on polysaccharides. Lignolytic fungi secrete a repertoire of extracellular enzymes during their secondary metabolism in response to nutrient limitation for non-specific oxidative degradation of lignin 4 . This enzyme array comprises phenol oxidases like laccase, heme peroxidases like lignin peroxidase, manganese peroxidase, versatile peroxidase and extracellular H 2 O 2 generating oxidases 5 .…”