Biotransformation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) by Alcaligenes eutrophus... more Biotransformation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) by Alcaligenes eutrophus A5 was demonstrated by analysis of ethyl acetate-extracted products from resting cell cultures. Gas chromatography-mass spectrometry characterization of the neutral extracts revealed two hydroxy-DDT intermediates (m/z = 370) with retention times at 19.55 and 19.80 min that shared identical mass spectra. This result suggested that the hydroxylations occurred at the ortho and meta positions on the aromatic ring. UV-visible spectrum spectrophotometric analysis of a yellow metabolite in the culture supernatant showed a maximum A402 with, under acidic and basic conditions, spectrophotometric characteristics similar to those of the aromatic ring meta-cleavage products. 4-Chlorobenzoic acid was detected by thin-layer chromatography radiochemical scanning in samples from mineralization experiments by comparison of Rf values of [14C]DDT intermediates with that of an authentic standard. These res...
Archives of Environmental Contamination and Toxicology, 1982
Page 1. Arch. Environm. Contain. Toxicol. 11,577-581 (1982) Archives of Environ mental Contaminat... more Page 1. Arch. Environm. Contain. Toxicol. 11,577-581 (1982) Archives of Environ mental Contamination and Toxicology Evaluation of the Mutagenic Potential of Bacterial Polychlorinated Biphenyl Biodegradation Products GS ...
A multivariate approach was used to evaluate the significance of synthetic oil-induced perturbati... more A multivariate approach was used to evaluate the significance of synthetic oil-induced perturbations in the functional activity of sediment microbial communities. Total viable cell densities, ATP-biomass, alkaline phosphatase and dehydrogenase activity, and mineralization rates of glucose, protein, oleic acid, starch, naphthalene, and phenanthrene were monitored on a periodic basis in microcosms and experimental ponds for 11 months, both before and after exposure to synthetic oil. All variables contributed to significant discrimination between sediment microbial responses in control communities and communities exposed to a gradient of synthetic oil contamination. At high synthetic oil concentrations (4,000 ml/12 m 3 ), a transient reduction in sediment ATP concentrations and increased rates of oleic acid mineralization were demonstrated within 1 week of exposure. These transient effects were followed within 1 month by a significant increase in rates of naphthalene and phenanthrene m...
A rapid Tenax-GC extraction technique has been evaluated for use in conjunction with aqueous biod... more A rapid Tenax-GC extraction technique has been evaluated for use in conjunction with aqueous biodegradation assays for polyaromatic hydrocarbons and polychlorinated biphenyls. The method was quantitatively efficient and reproducible for phenanthrene, but variable and not quantitative for Aroclor 1254 (polychlorinated biphenyls). Aqueous sample volumes and varying concentrations of organic matter influenced polychlorinated biphenyl and polyaromatic hydrocarbon extraction efficiency. Phenanthrene recovery was decreased by soil extract but unaffected by spent bacteriological culture medium. Both types of organic matter caused significant reduction of Aroclor 1254 recovery. Polyaromatic hydrocarbon and polychlorinated biphenyl biodegradation assays, performed with reservoir samples, supported the laboratory evaluation. The study demonstrated the utility of the Tenax-GC extraction technique for phenanthrene analysis in biodegradation assessment; however, Tenax-GC extraction was not appro...
Strains of Alcaligenes and Acinetobacter spp. were isolated from a mixed culture already proven t... more Strains of Alcaligenes and Acinetobacter spp. were isolated from a mixed culture already proven to be proficient at complete mineralization of monohalogenated biphenyls. These strains were shown to harbor a 35 X 10(6)-dalton plasmid mediating a complete pathway for 4-chlorobiphenyl (4CB) oxidation. Subsequent plasmid curing of these bacteria resulted in the abolishment of the 4CB mineralization phenotype and loss of even early 4CB metabolism by Acinetobacter spp. Reestablishment of the Alcaligenes plasmid, denoted pSS50, in the cured Acinetobacter spp. via filter surface mating resulted in the restoration of 4CB mineralization abilities. 4CB mineralization, however, proved to be an unstable characteristic in some subcultured strains. Such loss was not found to coincide with any detectable alteration in plasmid size. Cultures capable of complete mineralization, as well as those limited to partial metabolism of 4CB, produced 4-chlorobenzoate as a metabolite. Demonstration of mineraliz...
The effects of polychlorinated biphenyl (PCB) and phenanthrene stress on glucose uptake by natura... more The effects of polychlorinated biphenyl (PCB) and phenanthrene stress on glucose uptake by natural microbial populations were examined by the heterotrophic potential technique. Temporal and spatial distributions in glucose uptake velocities were examined for natural samples as well as PCB- and phenanthrene-stressed samples. Statistical analysis indicated significant variability among the various samples. It was demonstrated that the environmental variables contributed significantly to the variability in uptake kinetics. Although general trends indicated a PCB-induced stimulation in uptake velocities, these trends were in part masked by sample variability. Data analysis indicated no statistically significant PCB or phenanthrene effect on either total glucose uptake velocities or the proportion of 14CO2 evolved, as compared to natural unstressed samples.
SummaryActivated sludge was successful in reducing the levels of dissolved organic carbon (DOC) i... more SummaryActivated sludge was successful in reducing the levels of dissolved organic carbon (DOC) in coal slurry wastewaters. DOC removal by the activated sludge ranged from 61% to 97% with a large percentage (21–41%) of this DOC being completely metabolized to CO2. Second order kinetic constants (k2) developed for DOC removal ranged from 1.39·10−4 to 2.30·10−1 liter·day−1·(mg of sludge)−1, providing evidence that biological treatment was an effective mechanism for reducing the pollution potential of the slurry wastewaters. After treatment with activated sludge a residual DOC remained in the wastewater and data from ultrafiltration studies indicated that this residual carbon was of MW>1000. The activated sludge preferentially removed the lower (MW<1000) molecular weight compounds and the higher molecular weight DOC was more resistant to biological attack. However, extended acclimation (greater than 1 month) enabled the activated sludge to remove the higher molecular weight DOC from the slurry wastewaters.
ABSTRACT The Endocrine Disrupter Screening and Testing Advisory Committee (EDSTAC) created by the... more ABSTRACT The Endocrine Disrupter Screening and Testing Advisory Committee (EDSTAC) created by the Environmental Protection Agency (EPA) was mandated with developing methods to screen approximately 87,000 chemicals for biological effects on estrogen, androgen, and thyroid hormone systems. As part of this mandate, EDSTAC proposed that EPA develop rapid, high throughput screening systems to assess a compound&#39;s effects on hormonal systems. Recently, two yeast strains, S. cerevisiae BLYES and S. cerevisiae BLYAS, were developed that produce a rapid, measurable bioluminescent signal in response to either an estrogenic or androgenic compound, respectively. The BLYES assay produced a 17β-estradiol standard curve with an EC 50 value of 7.3 ± 3.1 x 10 -10 M (n = 20) and lower and upper limits of detection of 4.5 x 10 -11 to 2.8 x 10 -9 M. In the BLYAS assay using dihydrotestosterone as a standard, the lower limit of detection and the EC 50 values were 2.5 x 10 -9 M and (9.7 ± 4.6) x 10 -9 M (n = 17), respectively. In both assays, bioluminescence was observed in as little as 1 hour and data was collected in 3 – 4 hours. A third strain, S. cerevisiae BLYR which produces constant bioluminescence has also been developed to measure toxicity of each chemical, demonstrated by a decrease in bioluminescence. The primary advantages of these bioluminescent assays over colorimetric-based reporter assays include ease of use, efficiency of gathering data, and potential for use of multiple assays per microtiter plate. Further, when combined with appropriate photodetection technology, they may be used for rapid, remote monitoring of industrial and municipal waste effluents carrying hormonal active agents.
Additional file 3: Fig. S3. Tetracycline repressible autobioluminescent iPSC cells differentiated... more Additional file 3: Fig. S3. Tetracycline repressible autobioluminescent iPSC cells differentiated into cardiomyocytes and challenged with increasing concentrations of known cardiomodulators. PDF file demonstrating the use of autobioluminescent cardiomyocytes for cardiotoxicity screening. Similar to constitutively autobioluminescent iPSCs and iPSC-derived cardiomyocytes, the cells were capable of reporting changes in viability due to chemical challenge via corresponding changes in autobioluminescent output. Values are representative of N = 3 replicates. Error bars represent standard error of the means. p/s/cm2/sr; photons/second/cm2/steradian. Data is available at https://osf.io/h5qzj/ [15].
Biotransformation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) by Alcaligenes eutrophus... more Biotransformation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) by Alcaligenes eutrophus A5 was demonstrated by analysis of ethyl acetate-extracted products from resting cell cultures. Gas chromatography-mass spectrometry characterization of the neutral extracts revealed two hydroxy-DDT intermediates (m/z = 370) with retention times at 19.55 and 19.80 min that shared identical mass spectra. This result suggested that the hydroxylations occurred at the ortho and meta positions on the aromatic ring. UV-visible spectrum spectrophotometric analysis of a yellow metabolite in the culture supernatant showed a maximum A402 with, under acidic and basic conditions, spectrophotometric characteristics similar to those of the aromatic ring meta-cleavage products. 4-Chlorobenzoic acid was detected by thin-layer chromatography radiochemical scanning in samples from mineralization experiments by comparison of Rf values of [14C]DDT intermediates with that of an authentic standard. These res...
Archives of Environmental Contamination and Toxicology, 1982
Page 1. Arch. Environm. Contain. Toxicol. 11,577-581 (1982) Archives of Environ mental Contaminat... more Page 1. Arch. Environm. Contain. Toxicol. 11,577-581 (1982) Archives of Environ mental Contamination and Toxicology Evaluation of the Mutagenic Potential of Bacterial Polychlorinated Biphenyl Biodegradation Products GS ...
A multivariate approach was used to evaluate the significance of synthetic oil-induced perturbati... more A multivariate approach was used to evaluate the significance of synthetic oil-induced perturbations in the functional activity of sediment microbial communities. Total viable cell densities, ATP-biomass, alkaline phosphatase and dehydrogenase activity, and mineralization rates of glucose, protein, oleic acid, starch, naphthalene, and phenanthrene were monitored on a periodic basis in microcosms and experimental ponds for 11 months, both before and after exposure to synthetic oil. All variables contributed to significant discrimination between sediment microbial responses in control communities and communities exposed to a gradient of synthetic oil contamination. At high synthetic oil concentrations (4,000 ml/12 m 3 ), a transient reduction in sediment ATP concentrations and increased rates of oleic acid mineralization were demonstrated within 1 week of exposure. These transient effects were followed within 1 month by a significant increase in rates of naphthalene and phenanthrene m...
A rapid Tenax-GC extraction technique has been evaluated for use in conjunction with aqueous biod... more A rapid Tenax-GC extraction technique has been evaluated for use in conjunction with aqueous biodegradation assays for polyaromatic hydrocarbons and polychlorinated biphenyls. The method was quantitatively efficient and reproducible for phenanthrene, but variable and not quantitative for Aroclor 1254 (polychlorinated biphenyls). Aqueous sample volumes and varying concentrations of organic matter influenced polychlorinated biphenyl and polyaromatic hydrocarbon extraction efficiency. Phenanthrene recovery was decreased by soil extract but unaffected by spent bacteriological culture medium. Both types of organic matter caused significant reduction of Aroclor 1254 recovery. Polyaromatic hydrocarbon and polychlorinated biphenyl biodegradation assays, performed with reservoir samples, supported the laboratory evaluation. The study demonstrated the utility of the Tenax-GC extraction technique for phenanthrene analysis in biodegradation assessment; however, Tenax-GC extraction was not appro...
Strains of Alcaligenes and Acinetobacter spp. were isolated from a mixed culture already proven t... more Strains of Alcaligenes and Acinetobacter spp. were isolated from a mixed culture already proven to be proficient at complete mineralization of monohalogenated biphenyls. These strains were shown to harbor a 35 X 10(6)-dalton plasmid mediating a complete pathway for 4-chlorobiphenyl (4CB) oxidation. Subsequent plasmid curing of these bacteria resulted in the abolishment of the 4CB mineralization phenotype and loss of even early 4CB metabolism by Acinetobacter spp. Reestablishment of the Alcaligenes plasmid, denoted pSS50, in the cured Acinetobacter spp. via filter surface mating resulted in the restoration of 4CB mineralization abilities. 4CB mineralization, however, proved to be an unstable characteristic in some subcultured strains. Such loss was not found to coincide with any detectable alteration in plasmid size. Cultures capable of complete mineralization, as well as those limited to partial metabolism of 4CB, produced 4-chlorobenzoate as a metabolite. Demonstration of mineraliz...
The effects of polychlorinated biphenyl (PCB) and phenanthrene stress on glucose uptake by natura... more The effects of polychlorinated biphenyl (PCB) and phenanthrene stress on glucose uptake by natural microbial populations were examined by the heterotrophic potential technique. Temporal and spatial distributions in glucose uptake velocities were examined for natural samples as well as PCB- and phenanthrene-stressed samples. Statistical analysis indicated significant variability among the various samples. It was demonstrated that the environmental variables contributed significantly to the variability in uptake kinetics. Although general trends indicated a PCB-induced stimulation in uptake velocities, these trends were in part masked by sample variability. Data analysis indicated no statistically significant PCB or phenanthrene effect on either total glucose uptake velocities or the proportion of 14CO2 evolved, as compared to natural unstressed samples.
SummaryActivated sludge was successful in reducing the levels of dissolved organic carbon (DOC) i... more SummaryActivated sludge was successful in reducing the levels of dissolved organic carbon (DOC) in coal slurry wastewaters. DOC removal by the activated sludge ranged from 61% to 97% with a large percentage (21–41%) of this DOC being completely metabolized to CO2. Second order kinetic constants (k2) developed for DOC removal ranged from 1.39·10−4 to 2.30·10−1 liter·day−1·(mg of sludge)−1, providing evidence that biological treatment was an effective mechanism for reducing the pollution potential of the slurry wastewaters. After treatment with activated sludge a residual DOC remained in the wastewater and data from ultrafiltration studies indicated that this residual carbon was of MW>1000. The activated sludge preferentially removed the lower (MW<1000) molecular weight compounds and the higher molecular weight DOC was more resistant to biological attack. However, extended acclimation (greater than 1 month) enabled the activated sludge to remove the higher molecular weight DOC from the slurry wastewaters.
ABSTRACT The Endocrine Disrupter Screening and Testing Advisory Committee (EDSTAC) created by the... more ABSTRACT The Endocrine Disrupter Screening and Testing Advisory Committee (EDSTAC) created by the Environmental Protection Agency (EPA) was mandated with developing methods to screen approximately 87,000 chemicals for biological effects on estrogen, androgen, and thyroid hormone systems. As part of this mandate, EDSTAC proposed that EPA develop rapid, high throughput screening systems to assess a compound&#39;s effects on hormonal systems. Recently, two yeast strains, S. cerevisiae BLYES and S. cerevisiae BLYAS, were developed that produce a rapid, measurable bioluminescent signal in response to either an estrogenic or androgenic compound, respectively. The BLYES assay produced a 17β-estradiol standard curve with an EC 50 value of 7.3 ± 3.1 x 10 -10 M (n = 20) and lower and upper limits of detection of 4.5 x 10 -11 to 2.8 x 10 -9 M. In the BLYAS assay using dihydrotestosterone as a standard, the lower limit of detection and the EC 50 values were 2.5 x 10 -9 M and (9.7 ± 4.6) x 10 -9 M (n = 17), respectively. In both assays, bioluminescence was observed in as little as 1 hour and data was collected in 3 – 4 hours. A third strain, S. cerevisiae BLYR which produces constant bioluminescence has also been developed to measure toxicity of each chemical, demonstrated by a decrease in bioluminescence. The primary advantages of these bioluminescent assays over colorimetric-based reporter assays include ease of use, efficiency of gathering data, and potential for use of multiple assays per microtiter plate. Further, when combined with appropriate photodetection technology, they may be used for rapid, remote monitoring of industrial and municipal waste effluents carrying hormonal active agents.
Additional file 3: Fig. S3. Tetracycline repressible autobioluminescent iPSC cells differentiated... more Additional file 3: Fig. S3. Tetracycline repressible autobioluminescent iPSC cells differentiated into cardiomyocytes and challenged with increasing concentrations of known cardiomodulators. PDF file demonstrating the use of autobioluminescent cardiomyocytes for cardiotoxicity screening. Similar to constitutively autobioluminescent iPSCs and iPSC-derived cardiomyocytes, the cells were capable of reporting changes in viability due to chemical challenge via corresponding changes in autobioluminescent output. Values are representative of N = 3 replicates. Error bars represent standard error of the means. p/s/cm2/sr; photons/second/cm2/steradian. Data is available at https://osf.io/h5qzj/ [15].
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