Microbial Transformations of Azaarenes in Creosote-Contaminated Soil and Ground Water: Laboratory and Field Studies

Azaarenes or aromatic nitrogen heterocycles are a class of compounds found in wood-preservative wastes containing creosote. The fate and movement of these compounds in contaminated aquifers is not well understood. Water-quality studies in an aquifer contaminated with creosote near Pensacola, Florida, indicated that ground water was contaminated with several azaarenes and their oxygenated and alkylated derivatives, suggesting that these oxygenated compounds may be products of microbial transformation reactions. Accordingly, laboratory studies were designed to investigate the fate of these compounds. Under aerobic conditions, soil pseudomonads isolated from creosote-contaminated soil converted quinoline to 2(lH)quinolinone that subsequently was degraded to unknown products. A methanogenic consortium isolated from an anaerobic sewage digestor, in presence of ground-water and creosote-contaminated soil, converted quinoline, isoquinoline, and 4-methylquinoline to their respective oxygenated analogs. In addition, N-, C-, and O-methylated analogs of oxygenated azaarenes were identified by gas chromatography-mass spectrometry (GC-MS) in anaerobic cultures. Under the experimental conditions, 2-methylquinoline was biorefractory. Presence of similar biotransformation products in anaerobic cultures and contaminated ground water from the Pensacola site provided further evidence that these compounds indeed were microbial transformation products. Stable isotope labeling studies indicated that the source of the oxygen atom for this hydroxylation reaction under aerobic and anaerobic conditions was water. A mechanism was proposed for this hydroxylation reaction. Whereas parent azaarenes are biodegradable in both anaerobic and aerobic zones, oxygenated and alkylated analogs are more biorefractory and, hence, persistent in anaerobic zones of contaminated aquifers.

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Ecological Response in the Integrated Process of Biostimulation and Bioaugmentation of Diesel-Contaminated Soil

Applied Sciences ◽

10.3390/app11146305 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6305

Author(s):

Xiaosen Li ◽

Yakui Chen ◽

Xianyuan Du ◽

Jin Zheng ◽

Diannan Lu ◽

...

Keyword(s):

Nitrogen Cycle ◽

Contaminated Soil ◽

Quantitative Polymerase Chain Reaction ◽

Chemical Properties ◽

Gas Chromatography Mass Spectrometry ◽

Functional Genes ◽

Alkane Degradation ◽

Degrading Bacteria ◽

Polycyclic Aromatic ◽

Amine Compounds

The study applied microbial molecular biological techniques to show that 2.5% to 3.0% (w/w) of diesel in the soil reduced the types and number of bacteria in the soil and destroyed the microbial communities responsible for the nitrogen cycle. In the meantime, the alkane degradation gene alkB and polycyclic aromatic hydrocarbons (PAHs) degradation gene nah evolved in the contaminated soil. We evaluated four different remediation procedures, in which the biostimulation-bioaugmentation joint process reached the highest degradation rate of diesel, 59.6 ± 0.25% in 27 days. Miseq sequencing and quantitative polymerase chain reaction (qPCR) showed that compared with uncontaminated soil, repaired soil provides abundant functional genes related to soil nitrogen cycle, and the most significant lifting effect on diesel degrading bacteria γ-proteobacteria. Quantitative analysis of degrading functional genes shows that degrading bacteria can be colonized in the soil. Gas chromatography-mass spectrometry (GC-MS) results show that the components remaining in the soil after diesel degradation are alcohol, lipids and a small amount of fatty amine compounds, which have very low toxicity to plants. In an on-site remediation experiment, the diesel content decreased from 2.7% ± 0.3 to 1.12% ± 0.1 after one month of treatment. The soil physical and chemical properties returned to normal levels, confirming the practicability of the biosimulation-bioaugmentation jointed remediation process.

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Application of Bar Adsorptive Microextraction for the Determination of Levels of Tricyclic Antidepressants in Urine Samples

Molecules ◽

10.3390/molecules26113101 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3101

Author(s):

Mariana N. Oliveira ◽

Oriana C. Gonçalves ◽

Samir M. Ahmad ◽

Jaderson K. Schneider ◽

Laiza C. Krause ◽

...

Keyword(s):

Tricyclic Antidepressants ◽

Matrix Effects ◽

Activated Carbons ◽

Process Efficiency ◽

Gas Chromatography Mass Spectrometry ◽

Selected Ion Monitoring ◽

Experimental Conditions ◽

Analytical Methodology ◽

Low Efficiency

This work entailed the development, optimization, validation, and application of a novel analytical approach, using the bar adsorptive microextraction technique (BAμE), for the determination of the six most common tricyclic antidepressants (TCAs; amitriptyline, mianserin, trimipramine, imipramine, mirtazapine and dosulepin) in urine matrices. To achieve this goal, we employed, for the first time, new generation microextraction devices coated with convenient sorbent phases, polymers and novel activated carbons prepared from biomaterial waste, in combination with large-volume-injection gas chromatography-mass spectrometry operating in selected-ion monitoring mode (LVI-GC-MS(SIM)). Preliminary assays on sorbent coatings, showed that the polymeric phases present a much more effective performance, as the tested biosorbents exhibited low efficiency for application in microextraction techniques. By using BAμE coated with C18 polymer, under optimized experimental conditions, the detection limits achieved for the six TCAs ranged from 0.2 to 1.6 μg L−1 and, weighted linear regressions resulted in remarkable linearity (r2 > 0.9960) between 10.0 and 1000.0 μg L−1. The developed analytical methodology (BAμE(C18)/LVI-GC-MS(SIM)) provided suitable matrix effects (90.2–112.9%, RSD ≤ 13.9%), high recovery yields (92.3–111.5%, RSD ≤ 12.3%) and a remarkable overall process efficiency (ranging from 84.9% to 124.3%, RSD ≤ 13.9%). The developed and validated methodology was successfully applied for screening the six TCAs in real urine matrices. The proposed analytical methodology proved to be an eco-user-friendly approach to monitor trace levels of TCAs in complex urine matrices and an outstanding analytical alternative in comparison with other microextraction-based techniques.

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The effect of experimental conditions on the levels of oxidatively modified bases in DNA as measured by gas chromatography-mass spectrometry:

Free Radical Biology and Medicine ◽

10.1016/s0891-5849(99)00069-6 ◽

1999 ◽

Vol 27 (3-4) ◽

pp. 370-380 ◽

Cited By ~ 41

Author(s):

Sema Sentürker ◽

Miral Dizdaroglu

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Gas Chromatography Mass Spectrometry ◽

Experimental Conditions ◽

Chromatography Mass Spectrometry ◽

Oxidatively Modified

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TCE Removal from Contaminated Soil and Ground Water 1

Epa Environmental Engineering Sourcebook ◽

10.1201/9780203756720-6 ◽

2019 ◽

pp. 87-99 ◽

Cited By ~ 2

Author(s):

Hugh H. Russell ◽

John E. Matthews ◽

Guy W. Sewell

Keyword(s):

Ground Water ◽

Contaminated Soil

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Microbial Transformation of Isosteviol Lactone and Evaluation of the Transformation Products on Androgen Response Element

Journal of Natural Products ◽

10.1021/np070585b ◽

2008 ◽

Vol 71 (4) ◽

pp. 602-607 ◽

Cited By ~ 10

Author(s):

Bo-Hon Chou ◽

Li-Ming Yang ◽

Shwu-Fen Chang ◽

Feng-Lin Hsu ◽

Chia-Hsin Lo ◽

...

Keyword(s):

Microbial Transformation ◽

Transformation Products ◽

Response Element ◽

Androgen Response Element

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High-Throughput Identification of Microbial Transformation Products of Organic Micropollutants

Environmental Science & Technology ◽

10.1021/es100970m ◽

2010 ◽

Vol 44 (17) ◽

pp. 6621-6627 ◽

Cited By ~ 172

Author(s):

Damian E. Helbling ◽

Juliane Hollender ◽

Hans-Peter E. Kohler ◽

Heinz Singer ◽

Kathrin Fenner

Keyword(s):

High Throughput ◽

Microbial Transformation ◽

Transformation Products ◽

Organic Micropollutants

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First evidence of terrestrial ambrein formation in human adipocere

Scientific Reports ◽

10.1038/s41598-019-54730-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Barbara von der Lühe ◽

Robert W. Mayes ◽

Volker Thiel ◽

Lorna A. Dawson ◽

Matthias Graw ◽

...

Keyword(s):

Organic Molecule ◽

Soft Tissues ◽

Transformation Products ◽

Gas Chromatography Mass Spectrometry ◽

Post Mortem ◽

Sperm Whales ◽

Geological Samples ◽

Microbial Decomposition ◽

Chemical Indicators ◽

Waxy Substance

AbstractTo date, the only known occurrence of ambrein, an important perfumery organic molecule, is in coproliths found in about one in a hundred sperm whales. Jetsam ambergris coproliths from the whale are also found occasionally on beaches worldwide. Here we report on the surprising occurrence of ambrein in human adipocere. Adipocere is a waxy substance formed post-mortem during incomplete anaerobic decomposition of soft tissues. Adipocere samples obtained from grave exhumations were analysed using gas chromatography-mass spectrometry (GC-MS). In addition to the typical fatty acids of adipocere, lesser amounts of ambrein were identified in the samples, in abundances similar to those of the major accompanying faecal steroids. The distribution of these compounds suggests that ambrein was produced post-mortem during the microbial decomposition of faecal residues and tissues. It is assumed that the adipocere matrix of saturated fatty acidsaided the preservation of ambrein over extended periods of time, because adipocere is stable against degradation. The association of ambrein formation in ageing faecal material, under moist, oxygen-depleted conditions, now requires more attention in studies of other mammalian and geological samples. Indeed, ambrein and its transformation products may be useful novel chemical indicators of aged faecal matter and decomposed bodies.

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Quantitative proteomics of MDCK cells identify unrecognized roles of clathrin adaptor AP-1 in polarized distribution of surface proteins

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1821076116 ◽

2019 ◽

pp. 201821076 ◽

Cited By ~ 4

Author(s):

Paulo S. Caceres ◽

Diego Gravotta ◽

Patrick J. Zager ◽

Noah Dephoure ◽

Enrique Rodriguez-Boulan

Keyword(s):

Plasma Membrane ◽

Isotope Labeling ◽

Mdck Cells ◽

Current Model ◽

Large Population ◽

Adaptor Proteins ◽

Surface Proteins ◽

Experimental Conditions ◽

Large Populations ◽

Clathrin Adaptor

The current model of polarized plasma membrane protein sorting in epithelial cells has been largely generated on the basis of experiments characterizing the polarized distribution of a relatively small number of overexpressed model proteins under various experimental conditions. Thus, the possibility exists that alternative roles of various types of sorting machinery may have been underestimated or missed. Here, we utilize domain-selective surface biotinylation combined with stable isotope labeling with amino acids in cell culture (SILAC) and mass spectrometry to quantitatively define large populations of apical and basolateral surface proteins in Madin-Darby canine kidney (MDCK) cells. We identified 313 plasma membrane proteins, of which 38% were apical, 51% were basolateral, and 11% were nonpolar. Silencing of clathrin adaptor proteins (AP) AP-1A, AP-1B, or both caused redistribution of basolateral proteins as expected but also, of a large population of apical proteins. Consistent with their previously reported ability to compensate for one another, the strongest loss of polarity was observed when we silenced AP-1A and AP-1B simultaneously. We found stronger evidence of compensation in the apical pathway compared with the basolateral pathway. Surprisingly, we also found subgroups of proteins that were affected after silencing just one adaptor, indicating previously unrecognized independent roles for AP-1A and AP-1B. While AP-1B silencing mainly affected basolateral polarity, AP-1A silencing seemed to cause comparable loss of apical and basolateral polarity. Our results uncover previously overlooked roles of AP-1 in polarized distribution of apical and basolateral proteins and introduce surface proteomics as a method to examine mechanisms of polarization with a depth not possible until now.

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