Dibenzofuran degradation

Hammer E, D Krpowas, A Schafer, M Specht, W Erancke, E Schauer (1998) Isolation and characterization of a dibenzofuran-degrading yeast identification of oxidation and ring clavage products. Appl Environ Microbiol 64 2215-2219. 

Strubel V, K-H Engesser, P Fischer, H-J Knackmuss (1991) 3-(2-hydroxyphenyl)catechol as substrate for proximal meta ring cleavage in dibenzofuran degradation by Brevibacterium sp. strain DPO 1361. J Bacterial 173 1932-1937. 

The principal difference between adsorbed and solid substrates is that the latter are adsorbed to molecules of their own kind. With respect to their bioavailability, multilayer-sorbed molecules should behave like a solid substrate. A calculation shows that the direct uptake of truly adsorbed molecules is probably neither advantageous to bacteria nor can it be shown experimentally. Cells of the dibenzofuran-degrading Sphingomonas sp. HH19k consume at maximum 100 000 molecules per second [14], Assuming that an adhered cell touches a sorbent with 1% of its cell surface at a time, as was proposed by van Loosdrecht et al. [60], it would contact about 100000 sorbed molecules at a time, representing substrate for only one second. This does not contradict the possibility of direct uptake of truly adsorbed molecules, but it illustrates that such an uptake-mechanism would be relatively unimportant. 

Photolysis of all brominated dibenzodioxins investigated occurs very fast in n-hexane. The rate of degradation of all compounds follows a good first-order kinetic scheme. In Table 4 the calculated first order rate constants k are summarised along with the quantum-yields. The corresponding results for three brominated dibenzofurans are also included. 

Marine roseobacters that contain bacteriochlorophyll a have been described (Oz et al. 2005), and the bacteriochlorophyll a-containing marine bacterium Porphyrobacter sanguineus was able to degrade biphenyl and dibenzofuran, though unable to use them as sole substrates for growth (Hiraishi et al. 2002). 

The genus Staphylococcus is traditionally associated with disease in humans. The demonstration (Monna et al. 1993) that a strain of Staphylococcus auriculans—isolated by enrichment with dibenzofuran and with no obvions clinical association—could degrade this substrate and carry out limited biotransformation of hnorene and dibenzo[l,4]dioxin serves to illustrate the unsuspected metabolic potential of facultatively anaerobic Gram-positive organisms. 

Hiraishi A, Y Yonemitsu, M Matsushita, YK Shin, H Kuraishi, K Kawahara (2002) Characterization of Porphybacter sanguineus sp. nov., an aerobic bacteriochlorophyll-containing bacterium capable of degrading biphenyl and dibenzofuran. Arch Microbiol 178 45-52. 

Monna L, T Omori, T Kodama (1993) Microbial degradation of dibenzofuran, fluorene, and dibenzo-p-dioxin by Staphylococcus auriculans DBF63. Appl Environ Microbiol 59 285-289. 

Whereas the degradation of the carboxylates of the monocyclic furan, thiophene, and pyrrole is initiated by hydroxylation, degradation of their benzo analogs is generally carried out by dioxygenation. The degradation of the analogs dibenzofuran and dibenzo-[l,4]-dioxin is discussed in Part 2 of this chapter. 

Habe H, J-S Chung, J-H Lee, K Kasuga, T Yoshida, H Nojiri, T Omori (2001) Degradation of chlorinated dibenzofurans and dibenzo-/)-dioxins by two types of bacteria having angular dioxygenases with different features. Appl Environ Microbiol 67 3610-3617. 

Happe B, ED Eltis, H Poth, R Hedderich, KN Tunmis (1993) Characterization of 2,2, 3-trihydroxybiphenyl dioxygenase, an extradiol dioxygenase from the dibenzofuran- and dibenzo-/ -dioxin-degrading bacterium Sphingomonas sp. strain KWl. J Bacteriol 175 7313-7320. 

Takada S, M Nakamura, T Matsueda, R Kondo, K Sakai (1996) Degradation of polychlorinated dibenzo-/ -dioxins and polychlorinated dibenzofurans by the white rot fnngns Phanerochaete sordida YK-624. Appl Environ Microbiol 62 4323-4328. 

PLE pressurized liquid extraction, SPE solid phase extraction, UE ultrasonic extraction, DSPE dispersive solid phase extraction, SBSE stir bar sorptive extraction, TD-GC-MS thermal desorption-gas chromatography-mass spectrometry, LAS linear alkylbenzene sulfonates, CDEAs coconut diethanol amides, NPEOs nonylphenol ethoxylates, DP degradation products, SPC sulphenyl carboxylates, PCDD dibenzo-p-dioxins (PCDD), PCDF dibenzofurans, PCBs biphenyls... 

Carbazole, A-methylcarbazole, IV-ethylcarbazole, dibenzofuran, dibenzothiophene, fluorene, dibenzo-p-dioxin, phenoxathiin, phenoxazine, phenothiazine, xanthene, biphenyl, naphthalene, phenanthrene, anthracene, and fluoranthene could be transformed by E. coli, [314] which was transformed using a plasmid bearing the carAa, Ac, and Ad genes, and expressing only the carA-encoded proteins. Further work is needed to develop a final biocatalyst and to prove the advantages that this degradative pathway would incorporate in a refining bioprocess. 

Harms, H. and Zehnder, A. J. B. (1994). Influence of substrate diffusion on degradation of dibenzofuran and 3-chlorodibenzofuran by attached and suspended bacteria, Appl. Environ. Microbiol., 60, 2736-2745. 

Crosby, D.G., Moilanen, K.W., and Wong, A.S. Environmental generation and degradation of dibenzodioxins and dibenzofurans. Environ. Health Perspect., 5 259-266, 1973. 

That the traits of B. m aterium can be transferred to B. subtilis by plasmid transfer techniques has been established. These traits are increased resistance to naphthalene, parachlorbiphenyl, and dibenzofuran, and increased ability to degrade C-naphthalene. The transformants increased degradative abilities were demonstrated by the accumulation of greater quantitites of water soluble metabolite and the presence of a unique solvent soluble metabolite. 

It would be helpful to develop data determining the accuracy of PBDE determinations (e.g., percent recovery) in environmental samples. Methods for determining degradation products and metabolites of PBDE are needed. There is no information in the literature of detectable biodegradation of PBDEs in the environment under aerobic or anaerobic conditions. The analysis of PBDE pyrolysis degradation products, such as polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), is often disturbed by the presence of PBDEs. Ebert et al. (1999) demonstrated that by using a Florisil column ina sample clean-up process, almost complete separation of PBDEs and PBDD/Fs is achieved before analysis by GC-MS. 

Vollmuth, S. and Niessner R., Degradation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans during the UV/ozone treatment of pentachlo-rophenol-containing water, Toxicol. Environ. Chem., 61, 27-41, 1997. 

---