Strains of the soil fungus Mortierella show different degradation potentials for the phenylurea herbicide diuron.
Microbial pesticide degradation studies have until now mainly focused on bacteria, although fungi have also been shown to degrade pesticides. In this study we clarify the background for the ability of the common soil fungus Mortierella to degrade the phenylurea herbicide diuron. Diuron degradation potentials of five Mortierella strains were compared, and the role of carbon and nitrogen for the degradation process was investigated. Results showed that the ability to degrade diuron varied greatly among the Mortierella strains tested, and the strains able to degrade diuron were closely related. Degradation of diuron was fastest in carbon and nitrogen rich media while suboptimal nutrient levels restricted degradation, making it unlikely that Mortierella utilize diuron as carbon or nitrogen sources. Degradation kinetics showed that diuron degradation was followed by formation of the metabolites 1-(3,4-dichlorophenyl)-3-methylurea, 1-(3,4-dichlorophenyl)urea and an hitherto unknown metabolite suggested to be 1-(3,4-dichlorophenyl)-3-methylideneurea.
Department of Biology, Copenhagen University, Universitetsparken 15, 2100, Copenhagen Ø, Denmark, leael@bio.ku.dk.
Lea
L
Ellegaard-Jensen
Jens
J
Aamand
Birthe B
BB
Kragelund
Anders H
AH
Johnsen
Søren
S
Rosendahl
D001673:Biodegradation, Environmental / Q000187:drug effects; D018533:Biomass; D002244:Carbon / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D004237:Diuron / Q000737:chemistry / Q000378:metabolism*; D006540:Herbicides / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D016013:Likelihood Functions; D008969:Molecular Sequence Data; D020094:Mortierella / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D009584:Nitrogen / Q000494:pharmacology; D010802:Phylogeny; D012988:Soil Microbiology
D006540:Herbicides; D002244:Carbon; D004237:Diuron; D009584:Nitrogen