Laccase

Last updated
Laccase
Identifiers
EC no. 1.10.3.2
CAS no. 80498-15-3
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / QuickGO
Search
PMC articles
PubMed articles
NCBI proteins

Laccases (EC 1.10.3.2) are multicopper oxidases found in plants, fungi, and bacteria. Laccases oxidize a variety of phenolic substrates, performing one-electron oxidations, leading to crosslinking. For example, laccases play a role in the formation of lignin by promoting the oxidative coupling of monolignols, a family of naturally occurring phenols. [1] Other laccases, such as those produced by the fungus Pleurotus ostreatus , play a role in the degradation of lignin, and can therefore be classed as lignin-modifying enzymes. [2] Other laccases produced by fungi can facilitate the biosynthesis of melanin pigments. [3] Laccases catalyze ring cleavage of aromatic compounds. [4]

Contents

Laccase was first studied by Hikorokuro Yoshida in 1883 and then by Gabriel Bertrand [5] in 1894 [6] in the sap of the Japanese lacquer tree, where it helps to form lacquer, hence the name laccase.

Active site

The tricopper site found in many laccases; note that each copper center is bound to the imidazole sidechains of histidines (color code: copper is brown, nitrogen is blue). Cu3Im8laccase.png
The tricopper site found in many laccases; note that each copper center is bound to the imidazole sidechains of histidines (color code: copper is brown, nitrogen is blue).

The active site consists of four copper centers, which adopt structures classified as type I, type II, and type III. A tricopper ensemble contains types II and III copper (see figure). It is this center that binds O2 and reduces it to water. Each Cu(I,II) couple delivers one electron required for this conversion. The type I copper does not bind O2, but functions solely as an electron transfer site. The type I copper center consists of a single copper atom that is ligated to a minimum of two histidine residues and a single cysteine residue, but in some laccases produced by certain plants and bacteria, the type I copper center contains an additional methionine ligand. The type III copper center consists of two copper atoms that each possess three histidine ligands and are linked to one another via a hydroxide bridging ligand. The final copper center is the type II copper center, which has two histidine ligands and a hydroxide ligand. The type II together with the type III copper center forms the tricopper ensemble, which is where dioxygen reduction takes place. [7] The type III copper can be replaced by Hg(II), which causes a decrease in laccase activity. [1] Cyanide removes all copper from the enzyme, and re-embedding with type I and type II copper has been shown to be impossible. Type III copper, however, can be re-embedded back into the enzyme. A variety of other anions inhibit laccase. [8]

Laccases affects the oxygen reduction reaction at low overpotentials. The enzyme has been examined as the cathode in enzymatic biofuel cells. [9] They can be paired with an electron mediator to facilitate electron transfer to a solid electrode wire. [10] Laccases are some of the few oxidoreductases commercialized as industrial catalysts.

Activity in wheat dough

Laccases have the potential to crosslink food polymers such as proteins and nonstarch polysaccharides in dough. In non-starch polysaccharides, such as arabinoxylans (AX), laccase catalyzes the oxidative gelation of feruloylated arabinoxylans by dimerization of their ferulic esters. [11] These cross-links have been found to greatly increase the maximum resistance and decrease extensibility of the dough. The resistance was increased due to the crosslinking of AX via ferulic acid and resulting in a strong AX and gluten network. Although laccase is known to crosslink AX, under the microscope it was found that the laccase also acted on the flour proteins. Oxidation of the ferulic acid on AX to form ferulic acid radicals increased the oxidation rate of free SH groups on the gluten proteins and thus influenced the formation of S-S bonds between gluten polymers. [12] Laccase is also able to oxidize peptide-bound tyrosine, but very poorly. [12] Because of the increased strength of the dough, it showed irregular bubble formation during proofing. This was a result of the gas (carbon dioxide) becoming trapped within the crust so it could not diffuse out (like it would have normally) and causing abnormal pore size. [11] Resistance and extensibility was a function of dosage, but at very high dosage the dough showed contradictory results: maximum resistance was reduced drastically. The high dosage may have caused extreme changes in the structure of dough, resulting in incomplete gluten formation. Another reason is that it may mimic overmixing, causing negative effects on gluten structure. Laccase-treated dough had low stability over prolonged storage. The dough became softer and this is related to laccase mediation. The laccase-mediated radical mechanism creates secondary reactions of FA-derived radicals that result in breaking of covalent linkages in AX and weakening of the AX gel. [11]

Activity in wine

Laccase is produced by a number of fungal species that can infect grapes, most notably Botrytis cinerea Pers. (1794) [13] . Laccase is active at wine pH and its activity is not readily suppressed by sulfur dioxide. It has been noted to cause oxidative browning in white wines and loss of colour in red wines [14] [15] . It can also degrade a number of key phenolic compounds critical to wine quality [16] .

Biotechnology

The ability of laccases to degrade various aromatic polymers has led to research into their potential for bioremediation and other industrial applications. Laccases have been applied in the production of wines [17] as well as in the food industry. [18] [19] Studies utilizing fungal and bacterial laccases to degrade emerging pollutants have also been conducted. [20] [21] In particular, it has been shown that laccases can be applied to catalyze the degradation and detoxification a large range of aromatic contaminants, [22] including azo dyes, [23] [24] bisphenol A [25] and pharmaceuticals. [26] Transgenic plants whose roots secrete it could also be used in the same way. [27] [28]

See also

Related Research Articles

<span class="mw-page-title-main">Lignin</span> Structural phenolic polymer in plant cell walls

Lignin is a class of complex organic polymers that form key structural materials in the support tissues of most plants. Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity and do not rot easily. Chemically, lignins are polymers made by cross-linking phenolic precursors.

<span class="mw-page-title-main">Vanillin</span> Chemical compound

Vanillin is an organic compound with the molecular formula C8H8O3. It is a phenolic aldehyde. Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the extract of the vanilla bean. Synthetic vanillin is now used more often than natural vanilla extract as a flavoring in foods, beverages, and pharmaceuticals.

<i>Botrytis cinerea</i> Species of fungus

Botrytis cinerea is a necrotrophic fungus that affects many plant species, although its most notable hosts may be wine grapes. In viticulture, it is commonly known as "botrytis bunch rot"; in horticulture, it is usually called "grey mould" or "gray mold".

<span class="mw-page-title-main">Caffeic acid</span> Chemical compound

Caffeic acid is an organic compound with the formula (HO)2C6H3CH=CHCO2H. It is a yellow solid. Structurally, it is classified as a hydroxycinnamic acid. The molecule consists of both phenolic and acrylic functional groups. It is found in all plants as an intermediate in the biosynthesis of lignin, one of the principal components of biomass and its residues. It is unrelated to caffeine.

<span class="mw-page-title-main">Ferulic acid</span> Chemical compound

Ferulic acid is a hydroxycinnamic acid; it is an organic compound with the formula (CH3O)HOC6H3CH=CHCO2H. The name is derived from the genus Ferula, referring to the giant fennel (Ferula communis). Classified as a phenolic phytochemical, ferulic acid is an amber colored solid. Esters of ferulic acid are found in plant cell walls, covalently bonded to hemicellulose such as arabinoxylans. Salts and esters derived from ferulic acid are called ferulates.

<span class="mw-page-title-main">Mycoremediation</span> Process of using fungi to degrade or sequester contaminants in the environment

Mycoremediation is a form of bioremediation in which fungi-based remediation methods are used to decontaminate the environment. Fungi have been proven to be a cheap, effective and environmentally sound way for removing a wide array of contaminants from damaged environments or wastewater. These contaminants include heavy metals, organic pollutants, textile dyes, leather tanning chemicals and wastewater, petroleum fuels, polycyclic aromatic hydrocarbons, pharmaceuticals and personal care products, pesticides and herbicides in land, fresh water, and marine environments.

<span class="mw-page-title-main">Cytochrome b</span> Membrane protein involved in the electron transport chain

Cytochrome b within both molecular and cell biology, is a protein found in the membranes of aerobic cells. In eukaryotic mitochondria and in aerobic prokaryotes, cytochrome b is a component of respiratory chain complex III — also known as the bc1 complex or ubiquinol-cytochrome c reductase. In plant chloroplasts and cyanobacteria, there is an homologous protein, cytochrome b6, a component of the plastoquinone-plastocyanin reductase, also known as the b6f complex. These complexes are involved in electron transport, the pumping of protons to create a proton-motive force (PMF). This proton gradient is used for the generation of ATP. These complexes play a vital role in cells.

Nitrite reductase refers to any of several classes of enzymes that catalyze the reduction of nitrite. There are two classes of NIR's. A multi haem enzyme reduces NO2− to a variety of products. Copper containing enzymes carry out a single electron transfer to produce nitric oxide.

<span class="mw-page-title-main">Lignocellulosic biomass</span> Plant dry matter

Lignocellulose refers to plant dry matter (biomass), so called lignocellulosic biomass. It is the most abundantly available raw material on the Earth for the production of biofuels. It is composed of two kinds of carbohydrate polymers, cellulose and hemicellulose, and an aromatic-rich polymer called lignin. Any biomass rich in cellulose, hemicelluloses, and lignin are commonly referred to as lignocellulosic biomass. Each component has a distinct chemical behavior. Being a composite of three very different components makes the processing of lignocellulose challenging. The evolved resistance to degradation or even separation is referred to as recalcitrance. Overcoming this recalcitrance to produce useful, high value products requires a combination of heat, chemicals, enzymes, and microorganisms. These carbohydrate-containing polymers contain different sugar monomers and they are covalently bound to lignin.

Lignin-modifying enzymes (LMEs) are various types of enzymes produced by fungi and bacteria that catalyze the breakdown of lignin, a biopolymer commonly found in the cell walls of plants. The terms ligninases and lignases are older names for the same class, but the name "lignin-modifying enzymes" is now preferred, given that these enzymes are not hydrolytic but rather oxidative by their enzymatic mechanisms. LMEs include peroxidases, such as lignin peroxidase, manganese peroxidase, versatile peroxidase, and many phenoloxidases of the laccase type.

<span class="mw-page-title-main">Wood-decay fungus</span> Any species of fungus that digests moist wood, causing it to rot

A wood-decay or xylophagous fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as brown rot, and some, such as Armillaria, are parasitic and colonize living trees. Excessive moisture above the fibre saturation point in wood is required for fungal colonization and proliferation. In nature, this process causes the breakdown of complex molecules and leads to the return of nutrients to the soil. Wood-decay fungi consume wood in various ways; for example, some attack the carbohydrates in wood, and some others decay lignin. The rate of decay of wooden materials in various climates can be estimated by empirical models.

<i>Coriolopsis gallica</i> Species of fungus

Coriolopsis gallica is a fungus found growing on decaying wood. It is not associated with any plant disease, therefore it is not considered pathogenic. For various Coriolopsis gallica strains isolated, it has been found, as a common feature of the division Basidiomycota, that they are able to degrade wood components, mainly lignin and to lesser extent cellulose, which results in a degradation area covered by the accumulating -white- cellulose powder. Therefore, C. gallica might generically be called, as with many other basidiomycetes, a "white-rot" fungus.

<span class="mw-page-title-main">Bilirubin oxidase</span>

In enzymology, a bilirubin oxidase, BOD or BOx, (EC 1.3.3.5) is an enzyme encoded by a gene in various organisms that catalyzes the chemical reaction

Arabinoxylan is a form of the hemicellulose xylan found in both the primary and secondary cell walls of plants which in addition to xylose contains substantial amounts of another pentose sugar, arabinose. The term arabinoxylan usually refers to feruloyl-arabinoxylan from grasses and other commelinids containing moieties of the phenolic ferulic acid that can undergo oxidative coupling forming crosslinks between arabinoxylan chains and with lignin. Whilst arabinose has been found linked to xylan in non-commelinid plants, ferulic acid has not been reported on these and unlike feruloyl-arabinoxylan these arabinoxylans are not monophyletic. The remainder of this article refers to feruloyl-arabinoxylan from cell walls of grasses and other commelinid species.

<span class="mw-page-title-main">Grape reaction product</span> Chemical compound

The grape reaction product is a phenolic compound explaining the disappearance of caftaric acid from grape must during processing. It is also found in aged red wines. Its enzymatic production by polyphenol oxidase is important in limiting the browning of musts, especially in white wine production. The product can be recreated in model solutions.

<span class="mw-page-title-main">Multicopper oxidase</span> Class of enzymes

In molecular biology, multicopper oxidases are enzymes which oxidise their substrate by accepting electrons at a mononuclear copper centre and transferring them to a trinuclear copper centre; dioxygen binds to the trinuclear centre and, following the transfer of four electrons, is reduced to two molecules of water. There are three spectroscopically different copper centres found in multicopper oxidases: type 1, type 2 and type 3. Multicopper oxidases consist of 2, 3 or 6 of these homologous domains, which also share homology with the cupredoxins azurin and plastocyanin. Structurally, these domains consist of a cupredoxin-like fold, a beta-sandwich consisting of 7 strands in 2 beta-sheets, arranged in a Greek-key beta-barrel.

Myceliophthora thermophila is an ascomycete fungus that grows optimally at 45–50 °C (113–122 °F). It efficiently degrades cellulose and is of interest in the production of biofuels. The genome has recently been sequenced, revealing the full range of enzymes used by this organism for the degradation of plant cell wall material.

<span class="mw-page-title-main">Fungal extracellular enzyme activity</span> Enzymes produced by fungi and secreted outside their cells

Extracellular enzymes or exoenzymes are synthesized inside the cell and then secreted outside the cell, where their function is to break down complex macromolecules into smaller units to be taken up by the cell for growth and assimilation. These enzymes degrade complex organic matter such as cellulose and hemicellulose into simple sugars that enzyme-producing organisms use as a source of carbon, energy, and nutrients. Grouped as hydrolases, lyases, oxidoreductases and transferases, these extracellular enzymes control soil enzyme activity through efficient degradation of biopolymers.

This article covers protein engineering of cytochrome (CYP) P450 enzymes. P450s are involved in a range of biochemical catabolic and anabolic process. Natural P450s can perform several different types of chemical reactions including hydroxylations, N,O,S-dealkylations, epoxidations, sulfoxidations, aryl-aryl couplings, ring contractions and expansions, oxidative cyclizations, alcohol/aldehyde oxidations, desaturations, nitrogen oxidations, decarboxylations, nitrations, as well as oxidative and reductive dehalogenations. Engineering efforts often strive for 1) improved stability 2) improved activity 3) improved substrate scope 4) enabled ability to catalyze unnatural reactions. P450 engineering is an emerging field in the areas of chemical biology and synthetic organic chemistry (chemoenzymatic).

<span class="mw-page-title-main">Cytochrome P450 aromatic O-demethylase</span>

Cytochrome P450 aromatic O-demethylase is a bacterial enzyme that catalyzes the demethylation of lignin and various lignols. The net reaction follows the following stoichiometry, illustrated with a generic methoxy arene:

References

Citations

  1. 1 2 Solomon EI, Sundaram UM, Machonkin TE (November 1996). "Multicopper Oxidases and Oxygenases". Chemical Reviews. 96 (7): 2563–2606. doi:10.1021/cr950046o. PMID   11848837.
  2. ↑ Cohen R, Persky L, Hadar Y (April 2002). "Biotechnological applications and potential of wood-degrading mushrooms of the genus Pleurotus". Applied Microbiology and Biotechnology. 58 (5): 582–594. doi:10.1007/s00253-002-0930-y. PMID   11956739. S2CID   45444911.
  3. ↑ Lee D, Jang EH, Lee M, Kim SW, Lee Y, Lee KT, Bahn YS (October 2019). "Unraveling Melanin Biosynthesis and Signaling Networks in Cryptococcus neoformans". mBio. 10 (5): e02267-19. doi:10.1128/mBio.02267-19. PMC   6775464 . PMID   31575776.
  4. ↑ Claus H (2004). "Laccases: structure, reactions, distribution". Micron. 35 (1–2): 93–96. doi:10.1016/j.micron.2003.10.029. PMID   15036303.
  5. ↑ "Gabriel Bertrand on isimabomba" (in French).
  6. ↑ Lu GD, Ho PY, Sivin N (1980-09-25). Science and civilisation in China: Chemistry and chemical. Vol. 5. Cambridge University Press. p. 209. ISBN   9780521085731.
  7. ↑ Jones SM, Solomon EI (March 2015). "Electron transfer and reaction mechanism of laccases". Cellular and Molecular Life Sciences. 72 (5): 869–883. doi:10.1007/s00018-014-1826-6. PMC   4323859 . PMID   25572295.
  8. ↑ Alcalde M (2007). "Laccases: Biological functions, molecular structure and industrial applications.". In Polaina J, MacCabe AP (eds.). Industrial Enzymes. Springer. pp. 461–476. doi:10.1007/1-4020-5377-0_26. ISBN   978-1-4020-5376-4.
  9. ↑ Thorum MS, Anderson CA, Hatch JJ, Campbell AS, Marshall NM, Zimmerman SC, et al. (August 2010). "Direct, Electrocatalytic Oxygen Reduction by Laccase on Anthracene-2-methanethiol Modified Gold". The Journal of Physical Chemistry Letters. 1 (15): 2251–2254. doi:10.1021/jz100745s. PMC   2938065 . PMID   20847902.
  10. ↑ Wheeldon IR, Gallaway JW, Barton SC, Banta S (October 2008). "Bioelectrocatalytic hydrogels from electron-conducting metallopolypeptides coassembled with bifunctional enzymatic building blocks". Proceedings of the National Academy of Sciences of the United States of America. 105 (40): 15275–15280. Bibcode:2008PNAS..10515275W. doi: 10.1073/pnas.0805249105 . PMC   2563127 . PMID   18824691.
  11. 1 2 3 Selinheimo E (October 2008). Tyrosinase and laccase as novel crosslinking tools for food biopolymers. VTT Technical Research Centre of Finland. ISBN   978-951-38-7118-5.
  12. 1 2 Selinheimo E, Autio K, Kruus K, Buchert J (July 2007). "Elucidating the mechanism of laccase and tyrosinase in wheat bread making". Journal of Agricultural and Food Chemistry. 55 (15): 6357–6365. doi:10.1021/jf0703349. PMID   17602567.
  13. ↑ Zimdars S, Hitschler J, Schieber A, Weber F (2017). "Oxidation of wine polyphenols by secretomes of wild Botrytis cinerea strains from white and red grape varieties and determination of their specific laccase activity". J. Agric. Food Chem. 65: 10582–10590. doi:10.1021/acs.jafc.7b04375.
  14. ↑ Vignault A, Pascual O, Jourdes M, Moine V, Fermaud M, Roudet J, Canals JM, Teissedre PL, Zamora F (2019). "Impact of enological tannins on laccase activity". OENO One. 53. doi:10.20870/oeno-one.2019.53.1.2361.
  15. ↑ Giménez P, Just-Borràs A, Gombau J, Canals JM, Zamora F (2023). "Effects of laccase from Botrytis cinerea on the oxidative degradation of anthocyanins". OENO One. 57. doi:10.20870/oeno-one.2023.57.3.7567.
  16. ↑ Zimdars S, Hitschler J, Schieber A, Weber F (2017). "Oxidation of wine polyphenols by secretomes of wild Botrytis cinerea strains from white and red grape varieties and determination of their specific laccase activity". J. Agric. Food Chem. 65: 10582–10590. doi:10.1021/acs.jafc.7b04375.
  17. ↑ Minussi RC, Rossi M, Bologna L, Rotilio D, Pastore GM, Durán N (2007). "Phenols Removal in Musts: Strategy for Wine Stabilization by Laccase". J. Mol. Catal. B: Enzym. 45 (3): 102–107. doi:10.1016/j.molcatb.2006.12.004.
  18. ↑ Mayolo-Deloisa K, González-González M, Rito-Palomares M (2020). "Laccases in Food Industry: Bioprocessing, Potential Industrial and Biotechnological Applications". Frontiers in Bioengineering and Biotechnology. 8 (8): 222. doi: 10.3389/fbioe.2020.00222 . PMC   7105568 . PMID   32266246.
  19. ↑ Osma JF, Toca-Herrera JL, Rodríguez-Couto S (September 2010). "Uses of laccases in the food industry". Enzyme Research. 2010: 918761. doi: 10.4061/2010/918761 . PMC   2963825 . PMID   21048873.
  20. ↑ Wang X, Yao B, Su X (October 2018). "Linking Enzymatic Oxidative Degradation of Lignin to Organics Detoxification". International Journal of Molecular Sciences. 19 (11): 3373. doi: 10.3390/ijms19113373 . PMC   6274955 . PMID   30373305.
  21. ↑ Gasser CA, Ammann EM, Shahgaldian P, Corvini PF (December 2014). "Laccases to take on the challenge of emerging organic contaminants in wastewater" (PDF). Applied Microbiology and Biotechnology. 98 (24): 9931–9952. doi:10.1007/s00253-014-6177-6. PMID   25359481. S2CID   5773347.
  22. ↑ Sharma N, Leung IK (2021). "Novel thermophilic bacterial laccase for the degradation of aromatic organic pollutants". Front. Chem. 9: 711345. Bibcode:2021FrCh....9..880S. doi: 10.3389/fchem.2021.711345 . PMC   8564365 . PMID   34746090.
  23. ↑ Dai S, Yao Q, Yu G, Liu S, Yun J, Xiao X, et al. (2021). "Biochemical Characterization of a Novel Bacterial Laccase and Improvement of Its Efficiency by Directed Evolution on Dye Degradation". Frontiers in Microbiology. 12: 633004. doi: 10.3389/fmicb.2021.633004 . PMC   8149590 . PMID   34054745.
  24. ↑ Sharma N, Leung IK (November 2021). "Characterisation and optimisation of a novel laccase from Sulfitobacter indolifex for the decolourisation of organic dyes". International Journal of Biological Macromolecules. 190: 574–584. doi:10.1016/j.ijbiomac.2021.09.003. hdl: 2292/56774 . PMID   34506861. S2CID   237480679.
  25. ↑ Lassouane F, Aït-Amar H, Amrani S, Rodriguez-Couto S (January 2019). "A promising laccase immobilization approach for Bisphenol A removal from aqueous solutions". Bioresource Technology. 271: 360–367. Bibcode:2019BiTec.271..360L. doi:10.1016/j.biortech.2018.09.129. PMID   30293031. S2CID   52946036.
  26. ↑ Asif MB, Hai FI, Singh L, Price WE, Nghiem LD (2017). "Degradation of Pharmaceuticals and Personal Care Products by White-Rot Fungi—a Critical Review". Current Pollution Reports. 3 (2): 88–103. Bibcode:2017CPolR...3...88A. doi:10.1007/s40726-017-0049-5. S2CID   51897758.
  27. ↑ Singh Arora, Daljit; Kumar Sharma, Rakesh (2009-06-10). "Ligninolytic Fungal Laccases and Their Biotechnological Applications". Applied Biochemistry and Biotechnology . 160 (6). Springer: 1760–1788. doi:10.1007/s12010-009-8676-y. ISSN   0273-2289. PMID   19513857. S2CID   26012103.
  28. ↑ Tschofen, Marc; Knopp, Dietmar; Hood, Elizabeth; Stöger, Eva (2016-06-12). "Plant Molecular Farming: Much More than Medicines". Annual Review of Analytical Chemistry . 9 (1). Annual Reviews: 271–294. Bibcode:2016ARAC....9..271T. doi: 10.1146/annurev-anchem-071015-041706 . ISSN   1936-1327. PMID   27049632.

General sources

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.