Biodegradation of a biocide (Cu-N-cyclohexyldiazenium dioxide) component of a wood preservative by a defined soil bacterial community.
The wood protection industry has refined their products from chrome-, copper-, and arsenate-based wood preservatives toward solely copper-based preservatives in combination with organic biocides. One of these is Cu-HDO, containing the chelation product of copper and N-cyclohexyldiazenium dioxide (HDO). In this study, the fate of isotope-labeled ((13)C) and nonlabeled ((12)C) Cu-HDO incorporated in wood sawdust mixed with soil was investigated. HDO concentration was monitored by high-pressure liquid chromatography. The total carbon and the δ(13)C content of respired CO(2), as well as of the soil-wood-sawdust mixture, were determined with an elemental analyzer-isotopic ratio mass spectrometer. The concentration of HDO decreased significantly after 105 days of incubation, and after 24 days the (13)CO(2) concentration respired from soil increased steadily to a maximum after 64 days of incubation. Phospholipid fatty acid-stable isotope probing (PFA-SIP) analysis revealed that the dominant PFAs C(19:0)d8,9, C(18:0), C(18:1)ω7, C(18:2)ω6,9, C(17:1)d7,8, C(16:0), and C(16:1)ω7 were highly enriched in their δ(13)C content. Moreover, RNA-SIP identified members of the phylum Acidobacteria and the genera Phenylobacterium and Comamonas that were assimilating carbon from HDO exclusively. Cu-HDO as part of a wood preservative effectively decreased fungal wood decay and overall microbial respiration from soil. In turn, a defined bacterial community was stimulated that was able to metabolize HDO completely.
Jakobs-Schönwandt
Désirée
D
BAM, Federal Institute for Materials Research and Testing, IV.1, Biology in Materials Protection and Environmental Issues, Unter den Eichen 87, DE-12205 Berlin, Germany.
Mathies
Helena
H
Abraham
Wolf-Rainer
WR
Pritzkow
Wolfgang
W
Stephan
Ina
I
Noll
Matthias
M
D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D001711:Biotransformation; D002247:Carbon Isotopes / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D016000:Cluster Analysis; D003300:Copper / Q000378:metabolism*; D003510:Cyclohexanes / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004202:Disinfectants / Q000378:metabolism*; D007094:Imides / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013194:Staining and Labeling / Q000379:methods
D002247:Carbon Isotopes; D003510:Cyclohexanes; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D004202:Disinfectants; D007094:Imides; C469872:N-cyclohexyl-diazeniumdioxide; D012336:RNA, Ribosomal, 16S; D003300:Copper