Article

Cytochrome P450 monooxygenases involved in anthracene metabolism by the white-rot basidiomycete Phanerochaete chrysosporium.

Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
Applied Microbiology and Biotechnology (Impact Factor: 3.69). 08/2010; 87(5):1907-16. DOI: 10.1007/s00253-010-2616-1
Source: PubMed

ABSTRACT Cytochrome P450 monooxygenases (P450s) involved in anthracene metabolism by the white-rot basidiomycete Phanerochaete chrysosporium were identified by comprehensive screening of both catalytic potentials and transcriptomic profiling. Functional screening of P. chrysosporium P450s (PcCYPs) revealed that 14 PcCYP species catalyze stepwise conversion of anthracene to anthraquinone via intermediate formation of anthrone. Moreover, transcriptomic profiling explored using a complementary DNA microarray system demonstrated that 12 PcCYPs are up-regulated in response to exogenous addition of anthracene. Among the up-regulated PcCYPs, five species showed catalytic activity against anthracene. Based upon both catalytic and transcriptional properties, these five species are most likely to play major roles in anthracene metabolic processes in vivo. Thus, the combination of functional screening and a microarray system may provide a novel strategy for obtaining a thorough understanding of the catalytic functions and biological impacts of PcCYPs.

0 Bookmarks
 · 
54 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Microsomal fraction of fungal cells grabs the attention of many researchers for it contains enzymes that play a role in biotechnologically relevant processes. Microsomal enzymes, namely, CYP450s, were shown to metabolize a wide range of xenobiotic compounds, including PAHs, PCBs, dioxins, and endocrine disruptors, and take part in other fungal biotransformation reactions. However, little is known about the nature and regulation of these membrane-associated reactions. Advanced proteomic and post-genomic techniques make it possible to identify larger numbers of microsomal proteins and thus add to a deeper study of fungal intracellular processes. In this work, proteins that were identified through a shotgun proteomic approach in fungal microsomes under various culture conditions are reviewed. However, further research is still needed to fully understand the role of microsomes in fungal biodegradation and biotransformation reactions.
    Applied Microbiology and Biotechnology 11/2013; · 3.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The metabolic peculiarities of anthracene and pyrene by Pycnoporus sanguineus H1 were investigated. The fungus H1 could grow on the plate with anthracene and anthraquinone as the sole carbon source. In liquid medium, the strain degraded 8.5% of anthracene as the sole carbon source, with no ligninolytic enzymes was detected, indicating intracellular catabolic enzymes might be responsible for the initial oxidation of anthracene. When bran was added to media, the degradation rate of anthracene and pyrene increased to 71.3% and 30.2%, and laccase activities increased to a maximal value of 501.2 and 587.6 U/l, respectively. By GC-MS analysis, anthraquinone was detected as the unique intermediate product of anthracene oxidation, with yield molar ratio of 0.3. In vitro experiments showed that the extracellular culture fluid containing laccase transformed anthracene to anthraquinone with yield molar ratio of 1.0, which was less than that of in vivo experiment, indicating that anthraquinone could be further metabolized by the strain. Pyrene could not be oxidized by culture fluid. These results showed that both extracellular laccase and intracellular catabolic enzymes might play an important role in initial oxidation of anthracene while pyrene could be only oxidized by intracellular catabolic enzymes through co-metabolism. This article is protected by copyright. All rights reserved.
    Biotechnology and Applied Biochemistry 12/2013; · 1.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Genome sequencing of basidiomycetes, a group of fungi capable of degrading/mineralizing plant material, revealed the presence of numerous cytochrome P450 monooxygenases (P450s) in their genomes, with some exceptions. Considering the large repertoire of P450s found in fungi, it is difficult to identify P450s that play an important role in fungal metabolism and the adaptation of fungi to diverse ecological niches. In this study, we followed Sir Charles Darwin's theory of natural selection to identify such P450s in model basidiomycete fungi showing a preference for different types of plant components degradation. Any P450 family comprising a large number of member P450s compared to other P450 families indicates its natural selection over other P450 families by its important role in fungal physiology. Genome-wide comparative P450 analysis in the basidiomycete species, Phanerochaete chrysosporium, Phanerochaete carnosa, Agaricus bisporus, Postia placenta, Ganoderma sp. and Serpula lacrymans, revealed enrichment of 11 P450 families (out of 68 P450 families), CYP63, CYP512, CYP5035, CYP5037, CYP5136, CYP5141, CYP5144, CYP5146, CYP5150, CYP5348 and CYP5359. Phylogenetic analysis of the P450 family showed species-specific alignment of P450s across the P450 families with the exception of P450s of Phanerochaete chrysosporium and Phanerochaete carnosa, suggesting paralogous evolution of P450s in model basidiomycetes. P450 gene-structure analysis revealed high conservation in the size of exons and the location of introns. P450s with the same gene structure were found tandemly arranged in the genomes of selected fungi. This clearly suggests that extensive gene duplications, particularly tandem gene duplications, led to the enrichment of selective P450 families in basidiomycetes. Functional analysis and gene expression profiling data suggest that members of the P450 families are catalytically versatile and possibly involved in fungal colonization of plant material. To our knowledge, this is the first report on the identification and comparative-evolutionary analysis of P450 families enriched in model basidiomycetes.
    PLoS ONE 01/2014; 9(1):e86683. · 3.73 Impact Factor