A novel multicopper oxidase (laccase) from cyanobacteria: Purification, characterization with potential in the decolorization of anthraquinonic dye

Abstract

A novel extracellular laccase enzyme produced from Spirulina platensis CFTRI was purified by ultrafiltration, cold acetone precipitation, anion exchange and size exclusion chromatography with 51.5% recovery and 5.8 purification fold. The purified laccase was a monomeric protein with molecular mass of ~66 kDa that was confirmed by zymogram analysis and peptide mass fingerprinting. The optimum pH and temperature of the enzyme activity was found at 3.0 and 30°C using ABTS as substrate but the enzyme was quite stable at high temperature and alkaline pH. The laccase activity was enhanced by Cu+2, Zn+2 and Mn+2. In addition, the dye decolorization potential of purified laccase was much higher in terms of extent as well as time. The purified laccase decolorized (96%) of anthraquinonic dye Reactive blue- 4 within 4 h and its biodegradation studies was monitored by UV visible spectra, FTIR and HPLC which concluded that cyanobacterial laccase can be efficiently used to decolorize synthetic dye and help in waste water treatment.

Decolorization of Remazol Brilliant Blue R by laccase of newly isolated Leiotrametes flavida Strain ZUL62 from Bangka Heath Forest, Indonesia

“…The decolorization of RBBR, an anthraquinone dyes, was evaluated through the application of the purified laccase from Isolate ZUL62. We found the decolorization of RBBR was about 62% in the initial substrate concentration of 100 ppm within 24 h. Furthermore, other studies showed several results for decolorization of RBBR as follow: (i) T. versicolor U97 fungal culture was about 50% and 85% in 96 h and 144 d, respectively (Sari et al 2012b); (ii) Purified laccase of Arthrospira maxima was about 49% in 96 d (Afreen et al 2017); (iii) Purified laccase of Armaliraia sp F022 was about 70% in 48 h (Hadibarata et al 2012); (iv) purified laccase of Paraconiothyrium variabile was about 47% in 3 h by addition of laccase mediator (Forootanfar et al 2012). The increasing of RBBR concentration resulted in the reduction of decolorization (Figure 4).…”

Tree bark scrape fungus: A potential source of laccase for application in bioremediation of non-textile dyes

“…Fungal laccases typically have 3 to 10 glycosylation sites, and 10 to 50% of their molecular weight is attributed to glycosylation and deglycosylation of laccase affects its enzyme kinetics [56].After SDS-PAGE electrophoresis a band excised from the gel was subjected for identification by using MALDI_TOF analysis. A band at ~ 62 kDa was digested with trypsin into 10 fragments in the range of P1 to P10 (22 to 250 amino acid sequence) ( GAA87354.1) and confirmed that the purified enzyme was laccasev [57]. Km and Vmax of purified laccase were 26.8 mM which is a good activity of the enzyme.…”

Effects of flask configuration on biofilm growth and metabolites of intertidal Cyanobacteria isolated from a mangrove forest

“…The isocratic chromatographic separation parameters were-detection: PDA 254 nm; mobile phase: mixture of acetonitrile 60%, water 40%, flow rate of 1 ml min À1 . The total run time was 45 min (Challouf et al 2011;Afreen et al 2017).…”