Characterization of extracellular enzymatic extract obtained from Phlebia floridensis strain isolated from Yucatan Peninsula with a novel peroxidase and oxidase profile

White rot fungi can degrade different types of recalcitrant and xenobiotic compounds present in the environment due to their natural ability to modify chemical bonds of various phenolic components of lignin and their derivatives¹. Initially, twelve strains of fungi were isolated in the Yucatan Peninsula, only one of them demonstrated degradation on different dyes in preliminary screening; this strain was identified as Phlebia floridensis using ITS sequence analysis.

In the present work, extracellular enzymatic extract of this strain of P. floridensis was studied. More extensive screening assays were performed on agar minimal medium plates using phenolic and non-phenolic compounds, anthroquinone dyes and triphenyl methane dyes. As a result, P. floridensis strain was able to mineralize Aniline Blue, Methyl Blue, Brilliant Blue G250, Brilliant Blue R250, Malachite Green and the following substrates: 2,6-dimethoxyphenol (2,6 DMP), N,N-Dimethyl-p-phenylenediamine (DMPPDA), 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and Guaiacol (GUA). Thus, P. floridensis strain showed extremely versatile profile of enzymatic extract.

Subsequently, we determined the presence of proteins from 20 to 70 kDa using SDS-PAGE. After this, cation exchange chromatography was carried out establishing that the fraction with maximum activity was eluted at a concentration of 0.1M NaCl. This fraction was analyzed using different phenolic and non-phenolic compounds. Currently, we are performing HPLC-MS to determine the identity of enzymes present in the extracellular extract. Based on these results we suggest that this strain could be a source of novel peroxidases and oxidases useful in different biotechnological processes.

¹Martani, F., Beltrametti, F., Porro, D., Branduardi, P., & Lotti, M. (2017). The importance of fermentative conditions for the biotechnological production of lignin modifying enzymes from white-rot fungi. FEMS Microbiology Letters, 364(13).