Industrial and biotechnological applications of laccases: a review.

All aspects of microbiology, including virology, are covered. Areas of special interest include: physiology, biochemistry and genetics (including molecular biology and 'omic' studies); biotechnology and synthetic biology; pathogenicity (including medical, veterinary and plant pathogens particularly those relating to food security); environmental microbiology (including ecophysiology, ecogenomics and meta-omic studies); virology; food microbiology (from food production and spoilage to food-borne pathogens); taxonomy and systematics (including publication of novel species and taxonomic reclassifications), and professional development (including education, training, CPD, research assessment frameworks, research metrics, best-practice and history of microbiology).

FEMS microbiology letters

Enzymatic decolorization and degradation of azo dyes – A review

Laccases for removal of recalcitrant and emerging pollutants

Recently, the enzymatic approach has attracted much interest in the decolorization/degradation of textile and other industrially important dyes from wastewater as an alternative strategy to conventional chemical, physical and biological treatments, which pose serious limitations. Enzymatic treatment is very useful due to the action of enzymes on pollutants even when they are present in very dilute solutions and recalcitrant to the action of various microbes participating in the degradation of dyes. The potential of the enzymes (peroxidases, manganese peroxidases, lignin peroxidases, laccases, microperoxidase-11, polyphenol oxidases, and azoreductases) has been exploited in the decolorization and degradation of dyes. Some of the recalcitrant dyes were not degraded/decolorized in the presence of such enzymes. The addition of certain redox mediators enhanced the range of substrates and efficiency of degradation of the recalcitrant compounds. Several redox mediators have been reported in the literature, but very few of them are frequently used (e.g., 1-hydroxybenzotriazole, veratryl alcohol, violuric acid, 2-methoxy-phenothiazone). Soluble enzymes cannot be exploited at the large scale due to limitations such as stability and reusability. Therefore, the use of immobilized enzymes has significant advantages over soluble enzymes. In the near future, technology based on the enzymatic treatment of dyes present in the industrial effluents/wastewater will play a vital role. Treatment of wastewater on a large scale will also be possible by using reactors containing immobilized enzymes.

Potential Applications of the Oxidoreductive Enzymes in the Decolorization and Detoxification of Textile and Other Synthetic Dyes from Polluted Water: A Review

Enhancement of laccase production by Pleurotus ostreatus and its use for the decolorization of anthraquinone dye

Rhodobacter sphaeroides AS11737 decolorized more than 90% of several azo dyes (200 mg dyes l−1) in 24 h The optimal culture conditions were: anaerobic illumination (1990 lx), peptone as carbon source, temperature 35–40 °C and pH 7–8 Intracellular crude enzyme from this strain had azoreductase activity, optimized temperature as 45–50 °C, and decolorization kinetics which were consistent with a ping-pong mechanism

Decolorization of azo dyes by Rhodobacter sphaeroides.

The CO2 fixation ability of Rhodopseudomonas palustris DH was enhanced by introducing the recombinant plasmid pMG-CBBM containing the form II ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) gene (cbbM) isolated from Rps palustris NO 7 Sequencing of a 30-kb PstI fragment containing the cbbM gene revealed an open reading frame encoding 461 amino acids, homologous to known cbbM genes, with a ribosome binding site upstream of cbbM and a terminator downstream of cbbM, without promoter pMG-CBBM, a Rhodopseudomonas/Escherichia coli shuttle expression plasmid, was derived from the Rhodopseudomonas/E coli shuttle cloning vector pMG105, by inserting the promoter of the pckA gene and the cbbM gene into its multiple cloning site Plasmid pMG-CBBM was transformed into Rps palustris DH by electroporation, and was stably maintained when transformants were grown either photoheterotrophically or photolithoautotrophically in the absence of antibiotics This is the first report of an expression plasmid containing a Rps palustris-specific promoter that allows stable expression of a foreign gene in the absence of antibiotic selection

Cui-hong Du

Papers

Enhancement of laccase production by Pleurotus ostreatus and its use for the decolorization of anthraquinone dye

Decolorization of azo dyes by Rhodobacter sphaeroides.

Construction of a genetically engineered microorganism for CO2 fixation using a Rhodopseudomonas/Escherichia coli shuttle vector.