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Microbial Ecology May 1996Phenanthrene-degrading bacteria were isolated from enrichment cultures of soils contaminated with creosote and jet fuel. The isolates from the creosote enrichments were...
Phenanthrene-degrading bacteria were isolated from enrichment cultures of soils contaminated with creosote and jet fuel. The isolates from the creosote enrichments were classified by fatty acid methyl ester profiles as Acidovorax delafieldii and Sphingomonas paucimobilis; the bacterium from the jet fuel-contaminated soil was not identified and was designated strain JFD11. All three isolates used phenanthrene as a sole carbon and energy source, and two of the isolates used fluoranthene as a sole carbon and energy source. Anthracene and fluorene were cometabolized by all three strains, but pyrene was not transformed. Naphthalene inhibited all of the strains, and 28-h cultures of A. delafieldii were inhibited by naphthalene concentrations as low as 5 ppm. Short-term degradation experiments were undertaken with center-well flasks and concentrations of phenanthrene ranging from 1.2 to 12.0 &mgr;M. Since initial degradation rates were not a function of phenanthrene concentration, it was inferred that the half-saturation constants were less than the lowest phenanthrene concentration tested.
PubMed: 8661535
DOI: No ID Found -
FEMS Microbiology Letters Jun 1992Ribosomal rRNA gene fragments (rDNA) encompassing the 16S rDNA, the 16S-23S rDNA spacer region and part of the 23S rDNA of 95 strains belonging to 13 well-described taxa... (Comparative Study)
Comparative Study
Ribosomal rRNA gene fragments (rDNA) encompassing the 16S rDNA, the 16S-23S rDNA spacer region and part of the 23S rDNA of 95 strains belonging to 13 well-described taxa of the eubacterial family Comamonadaceae (beta subclass of the Proteobacteria or rRNA superfamily III) were enzymatically amplified using conserved primers. The fragments of approximately 2400 base pairs were subjected to restriction analysis. Restriction fragment length patterns obtained with HinfI enabled us to distinguish 9 of the 13 taxa studied. Restriction with CfoI was necessary to differentiate Acidovorax delafieldii from A. temperans and Hydrogenophaga flava from H. pseudoflava. The results indicate that amplified rDNA restriction analysis is a simple and reliable tool for the identification of bacterial species.
Topics: Base Sequence; DNA Restriction Enzymes; DNA, Bacterial; DNA, Ribosomal; Gram-Negative Aerobic Bacteria; Molecular Sequence Data; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length
PubMed: 1354195
DOI: 10.1111/j.1574-6968.1992.tb05102.x -
FEMS Microbiology Letters Aug 2000Various microorganisms were screened for their ability to degrade poly(tetramethylene succinate)-co-(tetramethylene adipate) (PBSA). Strain BS-3, which was newly...
Various microorganisms were screened for their ability to degrade poly(tetramethylene succinate)-co-(tetramethylene adipate) (PBSA). Strain BS-3, which was newly isolated from a soil sample, was selected as the best strain. From taxonomical studies, the strain was tentatively ascribed to belong to the genus Acidovorax, most probably to the species A. delafieldii. Strain BS-3 could degrade both solid and emulsified PBSA, and also emulsified poly(tetramethylene succinate). During the degradation, a lipase activity was observed in the culture broth. This lipase activity was induced more strongly by PBSA than by tributyrin or triolein which are typical substrates of lipase. These observations strongly suggest that this lipase was involved in the PBSA biodegradation in strain BS-3.
Topics: Adipates; Biodegradation, Environmental; Culture Media; Detergents; Gram-Negative Aerobic Rods and Cocci; Lipase; Plastics; Polyesters; Soil Microbiology; Substrate Specificity
PubMed: 10913861
DOI: 10.1111/j.1574-6968.2000.tb09201.x -
Chemosphere May 2018The potential of simultaneous removal of nitrate and phosphate from wastewater by a single anaerobic Fe(II) oxidizing denitrifiers (the strain PXL1) was assessed using...
The potential of simultaneous removal of nitrate and phosphate from wastewater by a single anaerobic Fe(II) oxidizing denitrifiers (the strain PXL1) was assessed using siderite biofilters under different influent TOC concentrations and hydraulic retention times (HRTs) over a 160-day trial. Higher TOC concentrations promoted NO removal, while there was no significant influence on PO removal. Lowering down HRT from 10 h to 5 h did not significantly influence NO and PO removal. The NO removal performance and microbial community structure in the biofilters indicated that NO was reduced to N by both strain PXL1 and heterotrophic Acidovorax delafieldii. Iron content analysis of the used siderite along the biofilters showed that PO removal was improved by the bio-oxidation of Fe(II) in siderite to Fe(III) via the strain PXL1. The coexistence of the strain PXL1 and natural siderite in nitrate-contaminated aquifers provides a practical technology for in situ remediation of nutrient contaminated waterbodies.
Topics: Autotrophic Processes; Bioreactors; Denitrification; Ferric Compounds; Filtration; Groundwater; Nitrates; Phosphates; Wastewater; Water Purification
PubMed: 29433026
DOI: 10.1016/j.chemosphere.2018.02.014 -
Applied Microbiology and Biotechnology Dec 1999Four polycyclic aromatic hydrocarbon (PAH)-degrading bacteria, namely Arthrobacter sulphureus RKJ4, Acidovorax delafieldii P4-1, Brevibacterium sp. HL4 and Pseudomonas...
Four polycyclic aromatic hydrocarbon (PAH)-degrading bacteria, namely Arthrobacter sulphureus RKJ4, Acidovorax delafieldii P4-1, Brevibacterium sp. HL4 and Pseudomonas sp. DLC-P11, capable of utilizing phenanthrene as the sole source of carbon and energy, were tested for its degradation using radiolabelled phenanthrene. [9-14C]Phenanthrene was incubated with microorganisms containing 100 mg/l unlabelled phenanthrene and the evolution of 14CO2 was monitored: within 18 h of incubation, 30.1, 35.6, 26.5 and 2.1% of the recovered radiolabelled carbon was degraded to 14CO2 by RKJ4, P4-1, HL4 and DLC-P11, respectively. When mixtures of other PAHs such as fluorene, fluoranthene and pyrene, in addition to phenanthrene, were added as additional carbon sources, there was a 36.1 and 20.6% increase in 14CO2 production from [9-14C]phenanthrene in the cases of RKJ4 and HL4, respectively, whereas P4-1 and DLC-P11 did not show any enhancement in 14CO2 production. Although, a combination of many bacteria enhances the degradation of organic compounds, no enhancement in the degradation of [9-14C]phenanthrene was observed in mixed culture involving all four microorganisms together. However, when different PAHs, as indicated above, were used in mixed culture, there was a 68.2% increase in 14CO2 production. In another experiment, the overall growth rate of P4-1 on phenanthrene could be enhanced by adding the non-ionic surfactant Triton X-100, whereas RKJ4, HL4 and DLC-P11 did not show any enhancement in growth. Pathways for phenanthrene degradation were also analysed by thin-layer chromatography, gas chromatography and gas chromatography-mass spectrometry. Common intermediates such as o-phthalic acid and protocatechuic acid were detected in the case of RKJ4 and o-phthalic acid was detected in the case of P4-1. A new intermediate, 1-naphthol, was detected in the cases of HL4 and DLC-P11. HL4 degrades phenanthrene via 1-hydroxy-2-naphthoic acid, 1-naphthol and salicylic acid, whereas DLC-P11 degrades phenanthrene via the formation of 1-hydroxy-2-naphthoic acid, 1-naphthol and o-phthalic acid. Both transformation sequences are novel and have not been previously reported in the literature. Mega plasmids were found to be present in RKJ4, HL4 and DLC-P11, but their involvement in phenanthrene degradation could not be established.
Topics: Bacteria; Biodegradation, Environmental; Biotransformation; Naphthols; Phenanthrenes; Plasmids; Surface-Active Agents
PubMed: 10645629
DOI: 10.1007/s002530051621 -
Canadian Journal of Microbiology May 1999Using a mixture of three mono nitrophenols as sole carbon, nitrogen and energy sources, mixed cultures were enriched from municipal activated sludge to degrade both...
Using a mixture of three mono nitrophenols as sole carbon, nitrogen and energy sources, mixed cultures were enriched from municipal activated sludge to degrade both nitrophenols and nitrobenzene. Bacterial growth and degradation rate could be increased by supplementing the medium with 0.1% YE. Microorganisms were isolated from the nitrophenols enrichment, and they were identified as strains of Comamonas testosteroni and Acidovorax delafieldii. These strains showed broad degradation ability toward nitrophenols and nitrobenzene.
Topics: Biodegradation, Environmental; Gram-Negative Aerobic Rods and Cocci; Nitrobenzenes; Nitrophenols; Sewage
PubMed: 10446720
DOI: No ID Found -
Analytical and Bioanalytical Chemistry Mar 1996A rapid and inexpensive test has been developed to investigate the influence of elevated heavy metal concentrations on the degradation of biodegradable plastics. Using...
A rapid and inexpensive test has been developed to investigate the influence of elevated heavy metal concentrations on the degradation of biodegradable plastics. Using an overlay agar technique it could be demonstrated that copper concentrations above 8 to 14 mg/L inhibit the degradation of powdered poly(3-hydroxybutyrate), (PHB), by Acidovorax delafieldii. This is the first study demonstrating the inhibiting influence of metals on the biodegradation of PHB.
PubMed: 15067488
DOI: 10.1007/s0021663540760