Laccase is essential for lignin degradation by the white‐rot fungus <i>Pycnoporus cinnabarinus</i>

Eggert, Claudia; Temp, Ulrike; Eriksson, Karl–Erik L.

doi:10.1016/s0014-5793(97)00301-3

Cited by 263 publications

(144 citation statements)

References 18 publications

Supporting

Mentioning

131

Contrasting

Unclassified

Order By: Relevance

“…3h) was the most effective compound for this kind of reaction [37]. A number of synthetic organic and inorganic mediators have been patented [36,38], and naturally occurring "native" mediators for laccases have been discovered and identified [39]. Moreover, the natural phenolic substrates of laccases, which are part of the extractive substances of wood, could also be the enhancers for the enzyme and increase the activity of laccase towards the lignin matrix during its destruction by fungi [40].…”

Section: Laccase Mediator System (Lms)mentioning

confidence: 99%

Laccases and Their Applications: A Patent Review

Kunamneni

Plou²,

Ballesteros³

et al. 2008

BIOT

278

172

View full text Add to dashboard Cite

Abstract:Laccases are an interesting group of multi copper enzymes, which have received much attention of researchers in last decades due to their ability to oxidize both phenolic and non-phenolic lignin related compounds as well as highly recalcitrant environmental pollutants. This makes these biocatalysts very useful for their application in several biotechnological processes. Such applications include the detoxification of industrial effluents, mostly from the paper and pulp, textile and petrochemical industries, polymer synthesis, bioremediation of contaminated soils, wine and beverage stabilization. Laccases are also used as catalysts for the manufacture of anti-cancer drugs and even as ingredients in cosmetics. Recently, the utility of laccases has also been applied to nanobiotechnology. This paper reviews recent and important patents related to the properties, heterologous production, molecular cloning, and applications of laccases within different industrial fields as well as their potential extension to the nanobiotechnology area.

show abstract

Section: Laccase Mediator System (Lms)mentioning

confidence: 99%

Laccases and Their Applications: A Patent Review

Kunamneni

Plou²,

Ballesteros³

et al. 2008

BIOT

278

172

View full text Add to dashboard Cite

show abstract

“…Laccases catalyse one-electron oxidation of a variety of phenolic compounds, with the concomitant fourelectron reduction of O 2 to H 2 O. They are involved in lignin biogenesis in higher plants, and lignin depolymerization by fungi (Eggert et al, 1997;Kirk & Farrell, 1987). Laccases also participate in a broad range of cellular processes such as sporulation (Leatham & Stahman, 1981), fruit body formation and plant pathogenesis (Choi et al, 1992;Geiger et al, 1986;Marbach et al, 1985).…”

Section: Introductionmentioning

confidence: 99%

Heterologous expression of laccase cDNA from Ceriporiopsis subvermispora yields copper-activated apoprotein and complex isoform patterns

et al. 2003

View full text Add to dashboard Cite

Analysis of genomic clones encoding a putative laccase in homokaryon strains of Ceriporiopsis subvermispora led to the identification of an allelic variant of the previously described lcs-1 gene. A cDNA clone corresponding to this gene was expressed in Aspergillus nidulans and in Aspergillus niger. Enzyme assays and Western blots showed that both hosts secreted active laccase. Relative to the isozymic forms of the native C. subvermispora enzyme, the A. niger-produced laccase had a higher molecular mass and gave a single band on IEF gels. In contrast, A. nidulans transformants secreted several isoforms remarkably similar to those of the native system. Considered together with previously reported Southern blots and protein sequencing, expression in A. nidulans supports the view that C. subvermispora has a single laccase gene and that multiple isoforms result from post-translational processes. In addition, several lines of evidence strongly suggest that under copper limitation, A. nidulans secretes apoprotein which can be reconstituted by a short incubation with Cu(I) and to a lesser extent with Cu(II).

show abstract

“…Degradative processes have been identified, for the related polymer lignin and ligninases of Phanerochaete chrysosporium have been shown to destroy fungal melanins (Butler & Day, 1998). Interestingly, the white rot fungus, Pycnoporus cinnabarinus, produces a metabolite, 3-hydroxyanthranilate, that mediates the oxidation of non-phenolic substrates by laccase that results in the depolymerization of lignin (Eggert et al, 1996b) and laccase is essential for the lignolytic ability of the fungus (Eggert et al, 1996a(Eggert et al, , 1997. Decolourization of melanin by the fungi Bjerkandera adusta, Galactomyces geotrichum, Trametes hirsuta and Trametes versicolor is a phenomenon consistent with the destruction of the pigment, which provides further evidence for the presence of melanin-degrading enzymes (Ratto et al, 2001).…”

Section: Discussionmentioning

confidence: 99%

Budding of melanized Cryptococcus neoformans in the presence or absence of l-dopa

Nosanchuk

Casadevall

2003

Microbiology

View full text Add to dashboard Cite

Cryptococcus neoformans is a pathogenic fungus that produces melanin when incubated in the presence of certain phenolic substrates such as L-3,4-dihydroxyphenylalanine (L-dopa). Melanin is an enigmatic polymer that is deposited in the cell wall and contributes to virulence. Substantial progress has been made in understanding the synthesis of melanin and the mechanisms by which it contributes to virulence, but relatively little is known about how melanin is rearranged during growth and budding. In this study we used transmission and scanning electron microscopy and immunofluorescence of melanized cells and melanin 'ghosts' to study the process of melanization during replication. Budding in melanized C. neoformans results in focal disruption of cell-wall melanin at the bud site. In the presence of L-dopa, bud-related melanin defects are repaired and daughter cells are melanized. However, in the absence of substrate, mother cells cannot repair their melanin defects and daughter cells are non-melanized. Hence, melanin in the parent cell is not carried to the daughter cells, but rather is synthesized de novo in buds. These results imply that melanin remodelling occurs during cell growth in a process that involves degradation and synthesis at sites of budding. INTRODUCTIONCryptococcus neoformans is an encapsulated, environmental fungus that can cause life-threatening meningitis, particularly in immunocompromised individuals. The ability of C. neoformans to make melanin was discovered in the early 1960s (Staib, 1962(Staib, , 1963 and was associated with virulence in the 1980s Rhodes et al., 1982). Melanins are rigid, acid-resistant polymers of uncertain structure that are found in all biological kingdoms (Hill, 1992). The synthesis of melanin by C. neoformans occurs only in the presence of phenolic compounds, such as L-3,4-dihydroxyphenylalanine (L-dopa), and is catalysed by a laccase Williamson, 1994). The C. neoformans laccase has recently been shown to be tightly associated with the cell wall by a hydrolysable bond (Zhu et al., 2001). When the fungus grows in the presence of phenolic compounds, melanin is deposited in the cell wall (Wang et al., 1995) and comprises approximately 15 % of the dry weight of late-stationary-phase melanized C. neoformans (Wang & Casadevall, 1996). C. neoformans is melanized in the environment (Nosanchuk et al., 1999b) and during human infection (Nosanchuk et al., 2000). In the environment melanin is thought to protect the fungus against extremes of temperature (Rosas & Casadevall, 1997), ultraviolet light (Wang & Casadevall, 1994a), heavy metals (Garcia-Rivera & Casadevall, 2001) and amoeboid predators (Steenbergen et al., 2001). During infection melanin appears to function in virulence by protecting fungal cells against microbicidal oxidants (Wang & Casadevall, 1994b) and peptides (Doering et al., 1999) produced by immune effector cells. Furthermore, melanin may interfere with the development of effective cellmediated responses (Huffnagle et al., 1995) and could affect the activation ...

show abstract

Laccase is essential for lignin degradation by the white‐rot fungus Pycnoporus cinnabarinus

Cited by 263 publications

References 18 publications

Laccases and Their Applications: A Patent Review

Laccases and Their Applications: A Patent Review

Heterologous expression of laccase cDNA from Ceriporiopsis subvermispora yields copper-activated apoprotein and complex isoform patterns

Budding of melanized Cryptococcus neoformans in the presence or absence of l-dopa

Contact Info

Product

Resources

About