Effect of various water-miscible solvents on enzymatic activity of fungal laccases

Rodakiewicz-Nowak, Janina; Kasture, Sangita M.; Dudek, B.; Haber, J.

doi:10.1016/s1381-1177(00)00183-1

Cited by 102 publications

(63 citation statements)

References 26 publications

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“…Addition of a water miscible solvent, such as ethanol or methanol, effected a decrease in enzyme activity, similar to those reported for the Cerrena unicolor laccase where ABTS was also used as the substrate [39]. However, organic solvents change the pH of aqueous solutions and hence, more factors could be contributing to the experimental data obtained [40]. Laccases are inhibited by metal chelators such as EDTA and more strongly by the copper chelators diethyldithiocarbamate (DDC) [2,41].…”

Section: Effect Of Inhibitorssupporting

confidence: 72%

An acid-stable laccase from Sclerotium rolfsii with potential for wool dye decolourization

Ryan

Schnitzhofer

Tzanov

et al. 2003

Enzyme and Microbial Technology

108

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The plant pathogen basidiomycete S. rolfsii secretes two laccases (SRL1 and SRL2) with molecular weights of 55 and 86 kDa, respectively. Laccase production was shown to be inducible by the addition of 2,5-xylidine to the cultural media. After treatment with a combination of chitinase and ␤-1,3-glucanase, two different laccases were isolated from the sclerotia depending on the stage of sclerotia development.The more prominent laccase, SRL1, was purified and found to decolourize the industrially important wool azo dye Diamond Black PV 200 without the addition of redox mediators. The enzyme (pI 5.2) was active in the acidic pH range, showing an optimal activity at pH 2.4, with ABTS as substrate. The optimum temperature for activity was determined to be 62 • C. Enzyme stability studies revealed that SRL1 was notably stable at 18 • C and pH 4.5, retaining almost full activity after a week. Oxidation of tyrosine was not detectable under the reaction conditions but the enzyme did oxidize a variety of the usual laccase substrates. SRL1 was strongly inhibited by sodium azide and fluoride. Dye solutions decolourized with the immobilized laccase were successfully used for redyeing.

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Section: Effect Of Inhibitorssupporting

confidence: 72%

An acid-stable laccase from Sclerotium rolfsii with potential for wool dye decolourization

Ryan

Schnitzhofer

Tzanov

et al. 2003

Enzyme and Microbial Technology

108

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“…LccA was relatively stable in all solvents examined, retaining nearly 75% of its activity after 24 h in methanol or ethanol and over 50% of its activity after incubation in DMSO or DMF. Prior studies (7,40,44,55,56) coupled with our current findings reveal that a wide variety of laccases, including LccA, are stable and/or can support catalysis and conversion of phenolic substrates in water-organic mixed solvents. Since most of the substrates and mediators of laccases are insoluble or poorly soluble in water and the degree of polymerization of phenoxyl radicals is higher in aqueous media (44), solvent stability is an important feature to consider in optimizing this group of enzymes.…”

supporting

confidence: 68%

LccA, an Archaeal Laccase Secreted as a Highly Stable Glycoprotein into the Extracellular Medium by Haloferax volcanii

Uthandi

Boutaiba

Humbard

et al. 2010

Appl Environ Microbiol

120

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Laccases couple the oxidation of phenolic compounds to the reduction of molecular oxygen and thus span a wide variety of applications. While laccases of eukaryotes and bacteria are well characterized, these enzymes have not been described in archaea. Here, we report the purification and characterization of a laccase (LccA) from the halophilic archaeon Haloferax volcanii. LccA was secreted at high levels into the culture supernatant of a recombinant H. volcanii strain, with peak activity (170 ؎ 10 mU ⅐ ml ؊1 ) at stationary phase (72 to 80 h). LccA was purified 13-fold to an overall yield of 72% and a specific activity of 29.4 U ⅐ mg ؊1 with an absorbance spectrum typical of blue multicopper oxidases. The mature LccA was processed to expose an N-terminal Ala after the removal of 31 amino acid residues and was glycosylated to 6.9% carbohydrate content. Purified LccA oxidized a variety of organic substrates, including bilirubin, syringaldazine (SGZ), 2,2,-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and dimethoxyphenol (DMP), with DMP oxidation requiring the addition of CuSO 4 . Optimal oxidation of ABTS and SGZ was at 45°C and pH 6 and pH 8.4, respectively. The apparent K m values for SGZ, bilirubin, and ABTS were 35, 236, and 670 M, with corresponding k cat values of 22, 29, and 10 s ؊1 , respectively. The purified LccA was tolerant of high salt, mixed organosolvents, and high temperatures, with a half-life of inactivation at 50°C of 31.5 h.Multicopper oxidases (MCOs) are a family of enzymes that include laccases (p-diphenol: dioxygen oxidoreductases; EC 1.10.3.2), ascorbate oxidases (EC 1.10.3.3), ferroxidases (EC 1.16.3.1), bilirubin oxidases (EC 1.3.3.5), and other enzyme subfamilies (27,65). MCOs couple the oxidation of organic and/or inorganic substrates to the four-electron reduction of molecular oxygen to water. These enzymes often have four Cu atoms classified into type 1 (T1), type 2 (T2), and type 3 (T3) centers, in which a mononuclear T1 center on the surface of the enzyme provides long-range intramolecular one-electron transfer from electron-donating substrates to an internal trinuclear T2-T3 center formed by a T2 Cu coordinated with a T3 Cu pair. The T2-T3 cluster subsequently reduces dioxygen to water.Enzymes of the laccase subfamily oxidize a broad range of compounds, including phenols, polyphenols, aromatic amines, and nonphenolic substrates, by one-electron transfer to molecular oxygen and thus have a wide variety of applications from biofuels to human health. The best-known application is the use of a laccase from the lacquer tree Rhus vernicifera in paint and adhesives for more than 6,000 years in East Asia (29). Laccases have also been used in the delignification of pulp, bleaching of textiles and carcinogenic dyes, detoxification of water and soils, removal of phenolics from wines, improving adhesive properties of lignocellulosic products, determination of bilirubin levels in serum, and transformation of antibiotics and steroids (60). In addition, laccases have demonstrated pote...

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“…However, the laccase may be denatured or it may be inhibited under these conditions [329,330]. In this regard laccases can be applied in nonaqueous solution or multiphasic systems.…”

Section: Potential New Laccase-based Biocatalystsmentioning

confidence: 99%

Laccases and Their Applications: A Patent Review

Kunamneni

Plou²,

Ballesteros³

et al. 2008

BIOT

278

172

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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.

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Effect of various water-miscible solvents on enzymatic activity of fungal laccases

Cited by 102 publications

References 26 publications

An acid-stable laccase from Sclerotium rolfsii with potential for wool dye decolourization

An acid-stable laccase from Sclerotium rolfsii with potential for wool dye decolourization

LccA, an Archaeal Laccase Secreted as a Highly Stable Glycoprotein into the Extracellular Medium by Haloferax volcanii

Laccases and Their Applications: A Patent Review

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