Publisher Summary Several procedures have been described for growing Phanerochaete chrysosporiurn for ligninase production. These procedures differ somewhat in the medium formulation and types of growth vessels: (1) shallow stationary cultures, (2) agitated liquid cultures, and (3) rotating biological contactors (RBCs; disk fermenters). The recently developed use of agitated culture for production of ligninase permits easier “scale up.” Although ligninase can be produced in agitated flask cultures, the reliable use of stirred tank fermenters awaits further development, which is ongoing in several laboratories. This chapter describes the production of ligninase in shallow stationary cultures and in agitated cultures. Shallow stationary cultures (10 ml) are grown in rubber-stoppered, 125-ml Edenmyer flasks at 39 ° under 100% oxygen. The stationary cultures give somewhat more reliable and reproducible results than the agitated cultures.

Lignin peroxidase of Phanerochaete chrysosporium

White-rot fungi and their enzymes for the treatment of industrial dye effluents.

The white rot fungus Phanerochaete chrysosporium degraded DDT [1,1,-bis(4-chlorophenyl)-2,2,2-trichloroethane], 3,4,3',4'-tetrachlorobiphenyl, 2,4,5,2',-4',5'-hexachlorobiphenyl, 2,3,7,8-tetrachlorodibenzo-p-dioxin, lindane (1,2,3,4,5,6-hexachlorocylohexane), and benzo[a]pyrene to carbon dioxide. Model studies, based on the use of DDT, suggest that the ability of Phanerochaete chrysosporium to metabolize these compounds is dependent on the extracellular lignin-degrading enzyme system of this fungus.

http://science.sciencemag.org/content/sci/228/4706/1434.full.pdf

Oxidation of persistent environmental pollutants by a white rot fungus.

Review: lignin conversion by manganese peroxidase (MnP)

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/0014-5793%2884%2980327-0

Separation and characterization of two extracelluar H2O2-dependent oxidases from ligninolytic cultures of Phanerochaete chrysosporium

An extracellular H2O2-requiring enzyme preparation involved in lignin biodegradation by the white rot basidiomycete Phanerochaete chrysosporium.

A pleiotropic mutant of Phanerochaete chrysosporium 104-2 lacking phenol oxidase and unable to form fruit bodies and a revertant strain 424-2 were isolated after UV mutagenesis. Strains 104-2 and 424-2 had no apparent dysfunction in primary metabolism with glucose as a carbon source. Unlike the wild type strain and strain 424-2, strain 104-2 was unable to evolve 14CO2 from 14C ring, side chain and 3-O-14C-methoxy labeled lignin. In addition, strain 104-2 was unable to evolve 14CO2 from a variety of lignin model compounds including 14C-4′-methoxy labeled veratrylglycerol-β-guaiacyl (V) ether, γ-14C-guaiacylglycerol-β-guaiacyl ether (VI), as well as 1-(14C-4′-methoxy, 3′-methoxyphenyl)1,2 propene (III) and 1-(14C-4′-methoxy-3′-methoxyphenyl) 1,2 dihydroxypropane (IV). The addition of peroxidase/H2O2 to cultures of strain 104-2 did not alter its capacity to degrade the labeled lignins. A variety of unlabeled lignin model compounds previously shown to be degraded by the wild type organism including β-aryl ether dimers and diaryl propane dimers were also not degraded by the mutant 104-2. The revertant strain 424-2 regained the capacity to degrade these compounds. The substrates described are degraded by oxygen requiring system(s) expressed during the secondary phase of growth, suggesting this pleiotropic mutant is possibly defective in the onset of postprimary metabolism. The inability of the mutant to produce the secondary metabolite veratryl alcohol and to elaborate enzymes in the veratryl alcohol biosynthetic pathway supports this hypothesis.

A Phanerochaete chrysosporium mutant defective in lignin degradation as well as several other secondary metabolic functions

Phanerochaete chrysosporium metabolized the radiolabeled lignin model compounds [γ-14C]guaiacylglycerol-β-guaiacyl ether and [4-methoxy-14C]veratrylglycerol-β-guaiacyl ether (VI) to 14CO2 in stationary and in shaking cultures. 14CO2 evolution was greater in stationary culture. 14CO2 evolution from [γ-14C]guaiacyl-glycerol-β-guaiacyl ether and [4-methoxy-14C]veratrylglycerol-β-guaiacyl ether in stationary cultures was two- to threefold greater when 100% O2 rather than air (21% O2) was the gas phase above the cultures. 14CO2 evolution from the metabolism of the substrates occurred only as the culture entered the stationary phase of growth. The presence of substrate levels of nitrogen in the medium suppressed 14CO2 evolution from both substrates in stationary cultures. [14C]veratryl alcohol and 4-ethoxy-3-methoxybenzyl alcohol were formed as products of the metabolism of VI and 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether, respectively.

Metabolism of Radiolabeled β-Guaiacyl Ether-Linked Lignin Dimeric Compounds by Phanerochaete chrysosporium

A soluble enzyme fraction from Phanerochaete chrysosporium catalyzed the oxidative decarboxylation of vanillic acid to methoxy-p-hydroquinone. The enzyme, partially purified by ammonium sulfate precipitation, required NADPH and molecular oxygen for activity. NADH was not effective. Optimal activity was displayed between pH 7.5–8.5. Neither EDTA, KCN, NaN3, nor o-phenanthroline (5 mM) were inhibitory. The enzyme was inducible with maximal activity displayed after incubation of previously grown cells with 0.1% vanillate for 30h.

Vanillate hydroxylase from the white rot basidiomycete Phanerochaete chrysosporium

A variety of auxotrophic strains of Phanerochaete chrysosporium were isolated after treatment of conidia with UV and X rays. Complementation studies with these strains demonstrated heterokaryotic mycelia and conidia in this organism. Nuclear staining also showed that conidia can be mono-, di-, or multinucleate. Complementation tests allowed the separation of each auxotrophic class with the same phenotype into complementation groups. (Refs. 15).

Mary B. Mayfield

Papers

An extracellular H2O2-requiring enzyme preparation involved in lignin biodegradation by the white rot basidiomycete Phanerochaete chrysosporium.

A Phanerochaete chrysosporium mutant defective in lignin degradation as well as several other secondary metabolic functions

Metabolism of Radiolabeled β-Guaiacyl Ether-Linked Lignin Dimeric Compounds by Phanerochaete chrysosporium

Vanillate hydroxylase from the white rot basidiomycete Phanerochaete chrysosporium

Isolation and Complementation Studies of Auxotrophic Mutants of the Lignin-Degrading Basidiomycete Phanerochaete chrysosporium