Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Biol Macromol ; 95: 920-927, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27793681

RESUMO

A novel laccase was purified from fermentation broth of the white rot fungus Cerrena unicolor strain GSM-01 following three ion-exchange chromatography steps and one gel-filtration step. The purified enzyme was determined to be a monomeric protein of 63.2kDa and demonstrated high oxidation activity of 2.05×104U/mg towards ABTS. Its cDNA, gene, and amino acid sequences were obtained. It possessed high sequence similarity with that of other laccases but different enzymatic properties. It manifested optimal pH and temperature of 2.6 and 45°C, respectively. Fe3+ and Fe2+ were the most efficient inhibitors towards Cerrena unicolor laccase (CUL), while Mn2+ can slightly enhance the laccase activity of 3.8-10.5%. The Km and Vmax of CUL were estimated to 302.7µM and 13.6µMm-1, respectively. CUL was effective in the decolorization of bromothymol blue, evans blue, methyl orange, and malachite green with decolorization efficiencies of 50%-85%. It possesses potential application in textile and environmental industries.


Assuntos
Corantes/metabolismo , Espaço Extracelular/enzimologia , Lacase/genética , Lacase/metabolismo , Polyporaceae/citologia , Sequência de Aminoácidos , Clonagem Molecular , Cor , Espaço Extracelular/genética , Concentração de Íons de Hidrogênio , Cinética , Lacase/química , Lacase/isolamento & purificação , Peso Molecular , Polyporaceae/enzimologia , Especificidade por Substrato , Temperatura
2.
Int J Biol Macromol ; 93(Pt A): 837-842, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27642125

RESUMO

A novel laccase was isolated from fermentation broth of the mycorrhizal fungus Leucoagaricus naucinus LAC-04 by using a protocol that comprising ion-exchange chromatography steps on DEAE-cellulose, SP-Sepharose, and Q-Sepharose, and finally gel filtration by fast protein liquid chromatography on Superdex 75. The laccase (LNL) was purified with a purification fold of 21.19 and a recovery rate of 19.8%. It is a monomeric protein with a molecular mass of 56kDa. LNL lacks absorption around 600nm, which indicates that the purified laccase is a yellow laccases. LNL demonstrates an optimal pH of 2.2 and an optimal temperature range of 30-60°C using ABTS as the substrate. It is inhibited in the presence of EDTA and metal ions including Cd2+, Co2+, Cu2+. The Km of the laccase towards ABTS is estimated to 50.12µM at pH 2.2 and 30°C. Moreover, the purified laccase manifests effective decolorizing activity towards azo, heterocyclic, and aromatic dyes including Bromothymol Blue, Eriochrome Black T, Evans Bue, Fuchsin Basic, and Remazol Brilliant Blue R.


Assuntos
Agaricales/enzimologia , Corantes/química , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Lacase/química , Lacase/isolamento & purificação , Estabilidade Enzimática , Concentração de Íons de Hidrogênio
3.
Int J Biol Macromol ; 81: 785-93, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26361865

RESUMO

A novel laccase was purified from fermentation broth of white rot fungus Trametes sp. LAC-01 using an isolation procedure involving three ion-exchange chromatography steps on DEAE-cellulose, SP-Sepharose, and Q-Sepharose, and one gel-filtration step. The purified enzyme (TSL) was proved as a monomeric protein with a Mr of 59kDa based on SDS-PAGE and FPLC. Partial amino acid sequences were obtained by LC-MS/MS sharing considerably high sequence similarity with that of other laccases. It possessed optimal pH of 2.6 and temperature of 60°C using ABTS as the substrate. The Km of the laccase toward ABTS was estimated to 30.28µM at pH 2.6 and 40°C. TSL manifested considerably high oxidizing activity toward ABTS, but was avoid of degradative activity toward benzidine, caftaric acid, etc. It was effective in the decolorization of phenolic dyes - Bromothymol Blue and Malachite Green with decolorization rate higher than 60% after 24h of incubation. Adjunction of Cu(2+) with the final concentration of 2.0mmol/L significantly activated laccase production with a steady high level of 275.8-282.2U/mL in 96-144h. The high yield and short production period makes Trametes sp. LAC-01 and TSL potentially useful for industrial and environmental application and commercialization.


Assuntos
Corantes/química , Fungos/enzimologia , Lacase/química , Cromatografia Líquida , Cobre/química , DNA Intergênico , Ativação Enzimática , Estabilidade Enzimática , Fermentação , Fungos/classificação , Fungos/genética , Concentração de Íons de Hidrogênio , Cinética , Lacase/biossíntese , Lacase/isolamento & purificação , Peso Molecular , Filogenia , Especificidade por Substrato , Espectrometria de Massas em Tandem , Temperatura , Trametes/classificação , Trametes/enzimologia , Trametes/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA