Increased PCP removal by Amylomyces rouxii transformants with heterologous Phanerochaete chrysosporium peroxidases supplementing their natural degradative pathway

Abstract

Fungal peroxidases and phenoloxidases are widely used in aromatic toxic compounds degradation. Peroxidases, such as lignin peroxidase and manganese peroxidase, as well as laccases are mainly produced by basidiomycetes and to a lower extent by other fungi, such as ascomycetes. Peroxidase-encoding genes have been described and homologous expression has been achieved in basidiomycetes. Heterologous expression has also been achieved in some non-producing peroxidase ascomycetes, like Penicillium and Aspergillus. In this work, heterologous expression of peroxidase-encoding genes, lignin peroxidase, and manganese peroxidase was achieved in a zygomycete producing only phenoloxidases (Amylomyces rouxii), aimed at coupling two different pathways used in nature for PCP removal in only one microbial strain. The ability of PCP removal was assayed with one of the obtained transformants, resulting in increased activity with respect to the ability of the parental strain cultured free of the inducer tyrosine (95% and 45%, respectively, of the initial PCP (12.5 mg L(-1)) in 120 h, or 100% and 49%, respectively, of the initial PCP after 144 h of liquid culture).

Heterologous Expression of Manganese Peroxidase in Aspergillus niger and Its Effect on Phenanthrene Removal from Soil

“…The intensity of the halo was different among the transformants, SCB2-T3 being the one with the most intense halo. These results are similar to findings by other authors, who screened autochthonous or recombinant fungal strains by the discoloration of Poly R-478 on agar plates and observed halos with different intensities induced by MnP activity [Abdelhafidh et al, 2005;Montiel-González et al, 2009;Moredo et al, 2003;Moreira et al, 2001;Tsukihara et al, 2006].…”

Mold Odor from Wood Treated with Chlorophenols despite Mold Growth That Can Only Be Seen Using a Microscope

“…The same search string in PubMed (see File S1 ) yielded 542 hits in contrast to 11,556 hits before restricting it to mold/mildew. Of these 542 papers, 28 remained [ 5 , 6 , 15 , 16 , 37 , 52 , 55 , 65 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 ] after excluding studies based on the title. Based on scrutiny of full papers or abstracts, none of the 28 studies addresses odor from PCs/CAs in relation to the extent of mold on treated wood.…”

Amylolytic fungi in starter cakes for rice beer production

“…All strains produce abundant chlamydospores (Ellis et al, 1976). A. rouxii have also been studied for the degradation of pentachlorophenol (PCP), which is a dangerous halogenated pollutant with persistence in the environment (Marcial et al, 2006;Montiel-González et al, 2009). The distinctive morphological characteristics of A. rouxii are the enormous number of chlamydospores produced in the aerial and substrate mycelium (Watanabe and Oda, 2008) which is seen in Fig.…”