Fungal microsomes in a biotransformation perspective: protein nature of membrane-associated reactions.

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.

The use of the fungus Dichomitus squalens for degradation in rotating biological contactor conditions.

Biodegradation potential of Dichomitus squalens in biofilm cultures and rotating biological contactor (RBC) was investigated. The fungus formed thick biofilms on inert and lignocellulosic supports and exhibited stable activities of laccase and manganese peroxidase to reach 40-62 and 25-32% decolorization of anthraquinone Remazol Brilliant Blue R and heterocyclic phthalocyanine dyes, respectively. The decolorization ceased when glucose concentration dropped to 1 mmol l(-1). In RBC reactor, respective decolorizations of Remazol Brilliant Blue R and heterocyclic Methylene Blue and Azure B dyes (50 mg l(-1)) attained 99%, 93%, and 59% within 7, 40 and 200 h. The fungus exhibited tolerance to coliform and non-coliform bacteria on rich organic media, the inhibition occurred only on media containing tryptone and NaCl. The degradation efficiency in RBC reactor, capability to decolorize a wide range of dye structures and tolerance to bacterial stress make D. squalens an organism applicable to remediation of textile wastewaters.