scholarly journals Differential Enantioselective Transformation of Atropisomeric Polychlorinated Biphenyls by Multiple Bacterial Strains with Different Inducing Compounds

2002 ◽  
Vol 68 (11) ◽  
pp. 5756-5759 ◽  
Author(s):  
Andrew C. Singer ◽  
Charles S. Wong ◽  
David E. Crowley
Keyword(s):  
Polychlorinated Biphenyls ◽  
Polychlorinated Biphenyl ◽  
Bacterial Strains ◽  
Pcb Congeners ◽  
Degrading Bacteria

ABSTRACT Five polychlorinated biphenyl (PCB)-degrading bacteria were tested for the ability to differentiate between the enantiomers of four atropisomeric PCB congeners (2,2′,3,6-tetra-CB; 2,2′,3,3′,6-penta-CB; 2,2′,3,4′,6-penta-CB; and 2,2′,3,5′,6-penta-CB) after growth in the presence of tryptone-soytone, biphenyl, carvone, or cymene. Enantioselectivity was shown to vary with respect to strain, congener, and cosubstrate.

scholarly journals Psychrotolerant Bacteria Isolated from Arctic Soil That Degrade Polychlorinated Biphenyls at Low Temperatures

1998 ◽  
Vol 64 (12) ◽  
pp. 4823-4829 ◽  
Author(s):  
Emma R. Master ◽  
William W. Mohn
Keyword(s):  
Dna Sequences ◽  
Burkholderia Cepacia ◽  
Polychlorinated Biphenyl ◽  
The Arctic ◽  
Cell Protein ◽  
Total Removal ◽  
Pcb Congeners ◽  
Arctic Soil ◽  
Degrading Bacteria ◽  
Aroclor 1242

ABSTRACT Psychrotolerant polychlorinated biphenyl (PCB)-degrading bacteria were isolated at 7°C from PCB-contaminated Arctic soil by using biphenyl as the sole organic carbon source. These isolates were distinguished from each other by differences in substrates that supported growth and substrates that were oxidized. 16S ribosomal DNA sequences suggest that these isolates are most closely related to the genus Pseudomonas. Total removal of Aroclor 1242, and rates of removal of selected PCB congeners, by cell suspensions of Arctic soil isolates and the mesophile Burkholderia cepacia LB400 were determined at 7, 37, and 50°C. Total removal values of Aroclor 1242 at 7°C by LB400 and most Arctic soil isolates were similar (between 2 and 3.5 μg of PCBs per mg of cell protein). However the rates of removal of some individual PCB congeners by Arctic isolates were up to 10 times higher than corresponding rates of removal by LB400. Total removal of Aroclor 1242 and the rates of removal of individual congeners by the Arctic soil bacteria were higher at 37°C than at 7°C but as much as 90% lower at 50°C than at 37°C. In contrast, rates of PCB removal by LB400 were higher at 50°C than at 37°C. In all cases, temperature did not affect the congener specificity of the bacteria. These observations suggest that the PCB-degrading enzyme systems of the bacteria isolated from Arctic soil are cold adapted.

scholarly journals Aerobic polychlorinated biphenyl-degrading bacteria isolated from the Tohoku region of Japan are not regionally endemic

2022 ◽  
pp. 1-12
Author(s):  
Tomijiro Hara ◽  
Yumiko Takatsuka
Keyword(s):  
Environmental Samples ◽  
Polychlorinated Biphenyl ◽  
Climatic Conditions ◽  
Aerobic Bacteria ◽  
Mountain Forest ◽  
Comamonas Testosteroni ◽  
Bacterial Strains ◽  
Heavy Snowfall ◽  
Degrading Bacteria ◽  
Gene Structures

In the Tohoku region of Japan, 72% of the land comprises mountain forest zones. During winter, severe climatic conditions include heavy snowfall. In such an environment, which is considered high in biodiversity, we assumed that aerobic bacteria would be diverse and would possess the ability to degrade polychlorinated biphenyls (PCBs). In this study, 78 environmental samples were collected from the Tohoku region and 56 aerobic PCB-degrading bacterial strains were isolated. They belonged to the genera Achromobacter, Rhodococcus, Pseudomonas, Stenotrophomonas, Comamonas, Pigmentiphaga, Xenophilus, Acinetobacter, and Pandoraea. Previously reported aerobic PCB-degrading bacterial strains isolated in Japan belonged to the same genera, except that the genera Acidovorax and Bacillus were not identified in the present study. In particular, the isolated Comamonas testosteroni strains YAZ2 and YU14-111 had high PCB-degrading abilities. Analysis of the sequences of the YAZ2 and YU14-111 strains showed that the gene structures of the bph operon, which encode enzymes associated with PCB degradation, were the same as those of the Acidovorax sp. KKS102 strain. Moreover, 2,3-biphenyl dioxygenase activity was responsible for the degradation characteristics of all the isolated strains. Overall, this study suggests that aerobic PCB-degrading bacteria are not specifically endemic to the Tohoku region but distributed across Japan.

scholarly journals Establishment of a Polychlorinated Biphenyl-Dechlorinating Microbial Consortium, Specific for Doubly Flanked Chlorines, in a Defined, Sediment-Free Medium

2000 ◽  
Vol 66 (1) ◽  
pp. 49-53 ◽  
Author(s):  
Qingzhong Wu ◽  
Kevin R. Sowers ◽  
Harold D. May
Keyword(s):  
South Carolina ◽  
Polychlorinated Biphenyls ◽  
Polychlorinated Biphenyl ◽  
Microbial Consortium ◽  
Enrichment Culture ◽  
Estuarine Sediment ◽  
The Other ◽  
Free Medium ◽  
Pcb Congeners ◽  
Carbon Bonds

ABSTRACT Estuarine sediment from Charleston Harbor, South Carolina, was used as inoculum for the development of an anaerobic enrichment culture that specifically dechlorinates doubly flanked chlorines (i.e., chlorines bound to carbon that are flanked on both sides by other chlorine-carbon bonds) of polychlorinated biphenyls (PCBs). Dechlorination was restricted to the para chlorine in cultures enriched with 10 mM fumarate, 50 ppm (173 μM) 2,3,4,5-tetrachlorobiphenyl, and no sediment. Initially the rate of dechlorination decreased upon the removal of sediment from the medium. However, the dechlorinating activity was sustainable, and following sequential transfer in a defined, sediment-free estuarine medium, the activity increased to levels near that observed with sediment. The culture was nonmethanogenic, and molybdate, ampicillin, chloramphenicol, neomycin, and streptomycin inhibited dechlorination activity; bromoethanesulfonate and vancomycin did not. Addition of 17 PCB congeners indicated that the culture specifically removes double flanked chlorines, preferably in the para position, and does not attack ortho chlorines. This is the first microbial consortium shown to para or metadechlorinate a PCB congener in a defined sediment-free medium. It is the second PCB-dechlorinating enrichment culture to be sustained in the absence of sediment, but its dechlorinating capabilities are entirely different from those of the other sediment-free PCB-dechlorinating culture, an ortho-dechlorinating consortium, and do not match any previously published Aroclor-dechlorinating patterns.

Studies on the transformation of selected polychlorinated biphenyl congeners by Pseudomonas strain LB 400

1997 ◽  
Vol 43 (8) ◽  
pp. 782-788 ◽  
Author(s):  
K. A. Billingsley ◽  
O. P. Ward ◽  
S. M. Backus
Keyword(s):  
Carbon Source ◽  
Polychlorinated Biphenyls ◽  
Incubation Period ◽  
Polychlorinated Biphenyl ◽  
Carbon Sources ◽  
Lag Phase ◽  
Resting Cells ◽  
Major Objective ◽  
Pcb Congeners ◽  
Degradation Medium

Resting cells of Pseudomonas strain LB400 are known to transform polychlorinated biphenyls (PCBs) when the cells are previously grown on biphenyl. In this study, PCB transformation was also observed in resting cells grown on other substrates such as glucose and glycerol. The presence of PCB congeners in the growth medium increased the lag phase for the growth of cells on a biphenyl substrate but not on a glycerol substrate. Supplementation of the degradation medium with biphenyl dramatically decreased the rate of PCB congener transformation, while the presence of glycerol or glucose had little or no effect on PCB transformation rates. Removal rates with biphenyl-grown cells in the standard degradation medium for 2,4,2′,4′-tetrachlorobiphenyl, 2,4,5,2′,5′-pentachlorobiphenyl, and 2,3-dichlorobiphenyl were 1.06, 1.66, and 224 μmol/(L∙h), respectively. Relative rates of transformation of 2,3-dichlorobiphenyl by biphenyl-, glucose-, and glycerol-grown cells were 100:36:36 and were similar to the relative rates of transformation of 2,4,5,2′,5′-pentachlorobiphenyl (100:33:42). The presence of PCBs adversely affected cell viability of biphenyl-grown cells over a 48-h incubation period and may explain the decline observed in PCB conversion capacity over the same incubation period. A major objective of this study was to investigate the significance of using biphenyl as the carbon source for growth of Pseudomonas strain LB400 cells capable of PCB transformation. Our findings indicate that, whereas higher rates of transformation of PCBs are observed with biphenyl-grown cells, cells grown on other carbon sources retain PCB-transforming enzymes. In addition, it has been demonstrated that biphenyl inhibits transformation of PCBs by the organism, whereas glycerol or glucose does not.Key words: Pseudomonas strain LB400, polychlorinated biphenyls, degradation, biphenyl.

scholarly journals Remediation potential of bacterial mixed cultures for polychlorinated biphenyls (PCBs) biodegradation

2019 ◽  
Vol 12 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Hana Horváthová ◽  
Katarína Lászlová ◽  
Katarína Dercová
Keyword(s):  
Polychlorinated Biphenyls ◽  
Mineral Water ◽  
Mixed Cultures ◽  
Contaminated Sediment ◽  
Bacterial Strains ◽  
Pcb Congeners ◽  
Naturally Occurring ◽  
Water Media ◽  
The Individual ◽  
Pcb Biodegradation

Abstract Remediation of polychlorinated biphenyls (PCBs) in minimal mineral water media in the presence of bacterial mixed cultures consisting of several individual strains is proposed. Starting from the fact that the properties and features of bacterial strains in mixed cultures can be supplemented and compensated, two-, three- and seven-membered mixed cultures (MC) were performed. The strains used for the construction of the MC were isolated from the waste canal of a former PCB producer. The highest biodegradation of 70 % of the sum of seven defined PCB congeners was achieved by two-membered MC containing the strains Rhodococcus sp. and Stenotrophomonas maltophilia added in the biomass ratio of 1 : 3 and 3 : 1. PCB biodegradation by a seven-membered MC was lower (58 %) but provided several benefits over the less-membered mixed cultures or the individual strains: similarity to naturally occurring microflora, easier preparation of the inocula, certain and repeatable results. Periodical reinoculation of the water media resulted to PCB biodegradation increase to 65 %. Seven-membered MC was applied to the historically PCB contaminated sediment as well, where a 59 % degradation of the sum of seven PCB congeners was determined.

Polychlorinated biphenyl induced hepatocyte alterations

1987 ◽  
Vol 45 ◽  
pp. 716-717
Author(s):  
D.N. Collins ◽  
J.N. Turner ◽  
K.O. Brosch ◽  
R.F. Seegal
Keyword(s):  
Lipid Droplets ◽  
Wistar Rats ◽  
Homovanillic Acid ◽  
Polychlorinated Biphenyl ◽  
Corn Oil ◽  
Environmental Pollutants ◽  
Short Term ◽  
Pcb Congeners ◽  
Urinary Levels ◽  
The Brain

Polychlorinated biphenyls (PCBs) are a ubiquitous class of environmental pollutants with toxic and hepatocellular effects, including accumulation of fat, proliferated smooth endoplasmic recticulum (SER), and concentric membrane arrays (CMAs) (1-3). The CMAs appear to be a membrane storage and degeneration organelle composed of a large number of concentric membrane layers usually surrounding one or more lipid droplets often with internalized membrane fragments (3). The present study documents liver alteration after a short term single dose exposure to PCBs with high chlorine content, and correlates them with reported animal weights and central nervous system (CNS) measures. In the brain PCB congeners were concentrated in particular regions (4) while catecholamine concentrations were decreased (4-6). Urinary levels of homovanillic acid a dopamine metabolite were evaluated (7).Wistar rats were gavaged with corn oil (6 controls), or with a 1:1 mixture of Aroclor 1254 and 1260 in corn oil at 500 or 1000 mg total PCB/kg (6 at each level).

Biodegradation of organophosphorus Pollutants by Soil Bacteria: Biochemical Aspects and Unsolved Problems

2020 ◽  
Vol 36 (4) ◽  
pp. 126-135
Author(s):  
T.V. Shushkova ◽  
D.O. Epiktetov ◽  
S.V. Tarlachkov ◽  
I.T. Ermakova ◽  
A.A. Leontievskii
Keyword(s):  
Genome Sequencing ◽  
Soil Bacteria ◽  
Activity Regulation ◽  
Bacterial Isolates ◽  
Bacterial Strains ◽  
Russian Science ◽  
Degrading Bacteria ◽  
Phosphorus Source ◽  
Glyphosate Herbicide ◽  
Enzymatic Pathways

The degradation of persistent organophosphorus pollutants have been studied in 6 soil bacterial isolates and in 3 bacterial strains adapted for utilization of glyphosate herbicide (GP) under laboratory conditions. Significant differences in the uptake of organophosphonates were found in taxonomically close strains possessing similar enzymatic pathways of catabolism of these compounds, which indicates the existence of unknown mechanisms of activity regulation of these enzymes. The effect of adaptation for GP utilization as a sole phosphorus source on assimilation rates of several other phosphonates was observed in studied bacteria. The newly found efficient stains provided up to 56% of GP decomposition after application to the soil in the laboratory. The unresolved problems of microbial GP metabolism and the trends for further research on the creation of reliable biologicals capable of decomposing organophosphonates in the environment are discussed. organophosphonates, glyphosate, biodegradation, bioremediation, C-P lyase, phosphonatase, degrading bacteria Investigation of phosphonatase and genome sequencing were supported by Russian Science Foundation Grant no. 18-074-00021.

scholarly journals Polychlorinated biphenyls and risk of hepatocellular carcinoma in the population living in a highly polluted area in Italy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Francesco Donato ◽  
Marco Moneda ◽  
Nazario Portolani ◽  
Angelo Rossini ◽  
Sarah Molfino ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Polychlorinated Biphenyls ◽  
Serum Levels ◽  
Polluted Area ◽  
Sufficient Evidence ◽  
Pcb Congeners ◽  
Non Hodgkin Lymphoma ◽  
And Gender ◽  
Few Data ◽  
Incident Cases

AbstractPolychlorinated biphenyls (PCBs) are human carcinogens, based on sufficient evidence for melanoma and limited evidence for non-Hodgkin lymphoma and breast cancer. Few data are available for liver cancer, although PCBs cause it in rats and determined liver damage in poisoned people. We investigated the association between PCB serum levels and hepatocellular carcinoma (HCC) with a case–control study in a PCB-polluted area in North Italy. We enrolled prospectively 102 HCC incident cases and 102 age and gender-matched hospital controls. Serum concentrations of 33 PCB congeners were determined by a gas chromatograph coupled to mass spectrometry. Of 102 HCC cases, 62 who had lost < 3 kg of body weight in past 3 years were included in the analysis (67.7% males, mean age 68 years). The odds ratio (OR) for HCC for 3rd compared to 1st tertile of PCB distribution was 1.76 (95% confidence interval 0.62–5.03) for total PCB, adjusting for socio-demographic variables and risk factors for HCC by logistic regression. For most PCB congeners, ORs > 1.5 or 2 were found, although the 95% CIs included the null value for almost all of them. This preliminary study suggests that PCBs might play a role in HCC development.

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