Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Apr 9:22:e00337.
doi: 10.1016/j.btre.2019.e00337. eCollection 2019 Jun.

Production of polyextremotolerant laccase by Achromobacter xylosoxidans HWN16 and Citrobacter freundii LLJ16

J O Unuofin  1   2 , H A Moubasher  3 , A I Okoh  1   2 , U U Nwodo  1   2
Affiliations

Production of polyextremotolerant laccase by Achromobacter xylosoxidans HWN16 and Citrobacter freundii LLJ16

J O Unuofin et al. Biotechnol Rep (Amst). .

Abstract

Given the upwelling of a variety of potential applications laccases could participate in, it would be fitting to equally make available laccases that are well suited for the aforementioned. Therefore historian understanding of the catalytic and physicochemical properties is desirable. Owing to this, the biochemical properties of the crude laccases from Achromobacter xylosoxidans HWN16 (Hb9c) and Citrobacter freundii LLJ 16 (Ie1c) were assessed. Furthermore, a hint of the molecular basis for their production from respective organisms was presented. Results showed that both laccases were tolerant, and sometimes had their activities improved by the set of parameters tested. They were active at broad range of temperature (0-90 °C), pH (3-11), and were equally thermo- and pH-stable. Their activities were either improved, or left unabated by cations, detergents, and chloride (5-40%), however, the highlight of the study was their augmented activity, when they were incubated with certain concentrations of fluoride (2-20%), a potent inhibitor. They were depicted to have multiple homologous laccase encoding genes, on molecular evaluation, which may be responsible the conferral of these remarkable qualities they possess. Therefore, the laccases might be beneficial, if employed in formulations for a wide range of environmental and biotechnological applications. Moreover, the molecular machinery of their production be exploited for economical benefits in the immediate future.

Keywords: Achromobacter xylosoxidans; Characterization; Citrobacter freundii; Laccase encoding genes; Polyextremotolerance.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Time course for extracellular laccase secretion from; (a) Achrmobacter xylosoxidans HWN16 (Hb9c), (b) Citrobacter freundii LLJ16 (Ie1c).
Fig. 2
Fig. 2
Effect of pH on laccase activity and stability; a&b (Hb9c: activity & stability), c&d (Ie1c: activity & stability).
Fig. 3
Fig. 3
Effect of temperature on laccase activity and stability; a&b (Hb9c: activity & stability), c&d (Ie1c: activity & stability).
Fig. 4
Fig. 4
Effect of potentially inhibitory compounds and halide on laccase activity in; a&b (Hb9c), c&d (Ie1c).
Fig. 5
Fig. 5
Effect of different concentrations of a potent halide, NaF on laccase activity in (a) Hb9c, (b) Ie1c.
Fig. 6
Fig. 6
Laccase substrate specificity studies of; (a) Hb9c, and (b) Ie1c.
Fig. 7
Fig. 7
Agarose gel electrophoresis (1.7% w/v) of fragments of laccase genes amplified by PCR on Achromobacter xylosoxidans HWN16 (Hb9c). Lane 1: ladder mix, lane 2: CueOP gene, lane 3: MCOStm gene, lane 4: CueOCit gene.
Fig. 8
Fig. 8
Agarose gel electrophoresis (1.7% w/v) of fragments of laccase genes amplified by PCR on Citrobacter freundii LLJ16 (Ie1c). Lane 1: ladder mix, lane 2: CueOP gene, lane 3: MCOStm gene, lane 4: CueOCit gene.
See this image and copyright information in PMC

References

    1. Rogalski J., Leonowicz A. Laccase. In: Pandey A., editor. Con Encyc Bioresour Technol. Food Products Press, Haworth Reference Press; New York: 2004. pp. 533–542.
    1. Mishra A., Kumar S. Cyanobacterial biomass as N-supplement to agrowaste for hyper-production of laccase from Pleurotus ostreatus in solid state fermentation. Process Biochem. 2007;42:681–685.
    1. Xu F. Effects of redox potential and hydroxide inhibition on the pH activity profile of fungal laccases. J. Biol. Chem. 1997;272(2):924–928. - PubMed
    1. Leonowicz A., Cho N.S., Luterek J., Wilkolazka A., Wojtas-Wasilewska M., Matuszewska A., Hofrichter M., Wesenberg D., Rogalski J. Fungal laccase: properties and activity on lignin. J. Basic Microbiol. 2001;41(3-4):185–227. - PubMed
    1. D’Souza D.T., Tiwari R., Sah A.K., Raghukumar C. Enhanced production of laccase by a marine fungus during treatment of coloured effluents and synthetic dyes. Enzyme Microb. Technol. 2006;38 540-511.

LinkOut - more resources