Activity and phylogenetic diversity of bacterial cells with high and low nucleic acid content and electron transport system activity in an upwelling ecosystem

We evaluated whether bacteria with higher cell-specific nucleic acid content (HNA) or an active electron transport system, i.e., positive for reduction of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), were responsible for the bulk of bacterioplankton metabolic activity. We also examined whether the phylogenetic diversity of HNA and CTC-positive cells differed from the diversity of Bacteria with low nucleic acid content (LNA). Bacterial assemblages were sampled both in eutrophic shelf waters and in mesotrophic offshore waters in the Oregon coastal upwelling region. Cytometrically sorted HNA, LNA, and CTC-positive cells were assayed for their cell-specific [³H]leucine incorporation rates. Phylogenetic diversity in sorted non-radioactively labeled samples was assayed using denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA genes. Cell-specific rates of leucine incorporation of HNA and CTC-positive cells were on average only slightly greater than the cell-specific rates of LNA cells. HNA cells accounted for most bacterioplankton substrate incorporation due to high abundances, while the low abundances of CTC-positive cells resulted in only a small contribution by these cells to total bacterial activity. The proportion of the total bacterial leucine incorporation attributable to LNA cells was higher in offshore regions than in shelf waters. Sequence data obtained from DGGE bands showed broadly similar phylogenetic diversity across HNA, LNA, and CTC-positive cells, with between-sample and between-region variability in the distribution of phylotypes. Our results suggest that LNA bacteria are not substantially different from HNA bacteria in either cell-specific rates of substrate incorporation or phylogenetic composition and that they can be significant contributors to bacterial metabolism in the sea

Fate of dispersants associated with the Deepwater Horizon oil spill

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of American Chemical Society for personal use, not for redistribution. The definitive version was published in Environmental Science & Technology 45 (2011):1298–1306, doi:10.1021/es103838p.Response actions to the Deepwater Horizon oil spill included the injection of ~771,000 gallons (2,900,000 L) of chemical dispersant into the flow of oil near the seafloor. Prior to this incident, no deepwater applications of dispersant had been conducted and thus no data exists on the environmental fate of dispersants in deepwater. We used ultrahigh resolution mass spectrometry and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to identify and quantify one key ingredient of the dispersant, the anionic surfactant DOSS (dioctyl sodium sulfosuccinate), in the Gulf of Mexico deepwater during active flow and again after flow had ceased. Here we show that DOSS was sequestered in deepwater hydrocarbon plumes at 1000-1200m water depth and did not intermingle with surface dispersant applications. Further, its concentration distribution was consistent with conservative transport and dilution at depth and it persisted up to 300 km from the well, 64 days after deepwater dispersant applications ceased. We conclude that DOSS was selectively associated with the oil and gas phases in the deepwater plume, yet underwent negligible, or slow, rates of biodegradation in the affected waters. These results provide important constraints on accurate modeling of the deepwater plume and critical geochemical contexts for future toxicological studies.The authors gratefully acknowledge funding from the National Science Foundation’s RAPID program (OCE-1045811 to EBK, OCE-1042097 to DLV, OCE-1042650 to J. D. Kessler for R/V Cape Hatteras cruise) and from the WHOI Director of Research. Instrumentation in the WHOI FT-MS facility was funded by the National Science Foundation MRI program (OCE-0619608) and by the Gordon and Betty T. Moore Foundation. Stipend support for A. Boysen was provided by the WHOI Summer Student Fellow Program

An approach to assessment of endocrine disruption in the National Children's Study.

In this article we consider the importance of assessing endocrine disruption in a large new cohort that has been proposed, the National Children's Study (NCS). We briefly review evidence that endocrine disruption is a potentially important hypothesis for human studies and weigh the need to assess endocrine disruption in the NCS. We note the salient features of earlier, similar cohort studies that serve as reference points for the design of the NCS. Finally, we discuss features of the NCS that would allow or enhance assessment of endocrine disruption, even if endocrine disruption were not a primary hypothesis motivating the study. At this time, the evidence supporting endocrine disruption in humans with background-level exposures is not strong. Thus, a compelling rationale for the NCS will probably need to be based on core hypotheses that focus on other issues. Nonetheless, if properly designed, the NCS could serve as an excellent resource for investigating future hypotheses regarding endocrine disruption

Pathway-centric analysis of microbial metabolic potential and expression along nutrient and energy gradients in the western Atlantic Ocean

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Cavaco, M. A., Bhatia, M. P., Hawley, A. K., Torres-Beltran, M., Johnson, W. M., Longnecker, K., Konwar, K., Kujawinski, E. B., & Hallam, S. J. Pathway-centric analysis of microbial metabolic potential and expression along nutrient and energy gradients in the western Atlantic Ocean. Frontiers in Marine Science, 9, (2022): 867310, https://doi.org/10.3389/fmars.2022.867310.Microbial communities play integral roles in driving nutrient and energy transformations in the ocean, collectively contributing to fundamental biogeochemical cycles. Although it is well known that these communities are stratified within the water column, there remains limited knowledge of how metabolic pathways are distributed and expressed. Here, we investigate pathway distribution and expression patterns from surface (5 m) to deep dark ocean (4000 m) at three stations along a 2765 km transect in the western South Atlantic Ocean. This study is based on new data, consisting of 43 samples for 16S rRNA gene sequencing, 20 samples for metagenomics and 19 samples for metatranscriptomics. Consistent with previous observations, we observed vertical zonation of microbial community structure largely partitioned between light and dark ocean waters. The metabolic pathways inferred from genomic sequence information and gene expression stratified with depth. For example, expression of photosynthetic pathways increased in sunlit waters. Conversely, expression of pathways related to carbon conversion processes, particularly those involving recalcitrant and organic carbon degradation pathways (i.e., oxidation of formaldehyde) increased in dark ocean waters. We also observed correlations between indicator taxa for specific depths with the selective expression of metabolic pathways. For example, SAR202, prevalent in deep waters, was strongly correlated with expression of the methanol oxidation pathway. From a biogeographic perspective, microbial communities along the transect encoded similar metabolic potential with some latitudinal stratification in gene expression. For example, at a station influenced by input from the Amazon River, expression of pathways related to oxidative stress was increased. Finally, when pairing distinct correlations between specific particulate metabolites (e.g., DMSP, AMP and MTA) and both the taxonomic microbial community and metatranscriptomic pathways across depth and space, we were able to observe how changes in the marine metabolite pool may be influenced by microbial function and vice versa. Taken together, these results indicate that marine microbial communities encode a core repertoire of widely distributed metabolic pathways that are differentially regulated along nutrient and energy gradients. Such pathway distribution patterns are consistent with robustness in microbial food webs and indicate a high degree of functional redundancy.This work was funded by the NSF Division of Ocean Sciences (Grant no. OCE-1154320 to EK and KL) and a small (“Microbial controls on marine organic carbon cycling”) and large (“Marine microbial communities from the Southern Atlantic Ocean transect to study dissolved organic matter and carbon cycling”) community sequencing grants from the Joint Genome Institute (US Department of Energy, Walnut Creek, CA) to SH and MB. MB was supported by an NSERC post-doctoral fellowship and a CIFAR Global Scholars fellowship. MC was supported by a Campus Alberta Innovates Program (CAIP) chair to MB

Longitudinal assessment of PCBs and chlorinated pesticides in pregnant women from Western Canada

BACKGROUND: Maternal exposures to organochlorines prior to pregnancy are considered a risk to neonatal welfare, specifically in relation to neurocognitive functions. There is growing interest in the evaluation of maternal blood testing as a marker for fetal exposure as well as the variable geographic distribution of these priority chemicals. METHODS: Three hundred and twenty-three women in the second trimester of pregnancy entered the study at a prenatal clinic providing genetic counselling information. Subjects who had an indication for genetic amniocentesis based on late maternal age were eligible to participate. Two hundred and thirty-eight completed an environmental questionnaire. A sample of amniotic fluid was taken for karyotype analysis in 323 women and blood samples during pregnancy (209), at birth (105) and from the umbilical cord (97) and breast milk (47) were also collected. These samples were tested for 29 PCB congeners and organochlorine pesticides. RESULTS: The concentrations of PCB 153 in these media were relatively low in relation to other studies. Σ PCBs measurements in samples taken during the second trimester of pregnancy, at birth and in the umbilical cord were strongly correlated. Specific measurements of PCB 153 and PCB 180 among those subjects with completed sampling of blood samples from mothers and cord samples were significantly correlated. The concentrations of PCBs and pesticides did not differ in relation to prior spontaneous abortion history. There were no organochlorines present in the amniotic fluid at the current level of quantification. CONCLUSION: Pregnant women from the Western Canada region of Calgary, Alberta are exposed to relatively low concentrations of organochlorines. Measurement of maternal blood during the second trimester of pregnancy can reliably estimate the fetal exposure to PCBs. This estimate is reliable for Group 2 and 3 PCBs as well as PCB 153 and PCB 180. The amniotic fluid does not contain measurable concentrations of pesticides and PCBs under the conditions of the levels of quantification

Serum α-Tocopherol Concentration in Relation to Subsequent Colorectal Cancer: Pooled Data From Five Cohorts

Background Numerous monoclonal antibodies (MAbs) have been produced to antigens found in human melanomas. Three of the best characterized melanoma antigens include the melanoma-associated glycoproteins (MAGs) defined by two reagent families—the ME491 family (including ME491, 8-1H, and 8-2A) and the NKI/C-3 family (including NKI/C-3 and NKI/black-13)—as well as the neuroglandular antigen (NGA) defined by MAbs LS59, LS62, and LS140. These three antigens have significant similarities in tissue distribution, biosynthesis, and structure. The ME491 MAG has been cloned, mapped, and sequenced. Numerous non-melanoma-associated proteins (Sm23, CO-029, R2, TAPA-1, CD9, CD37, CD53, and CD63) have recently been shown to have significant homology to this sequence. Purpose We conducted this study to investigate the similarity between the two MAG antigens and NGA. Methods Several reagents defining the three different melanoma antigens were compared, using competition immunoprecipitation, immunoas-say, and inhibition radioimmunoassay techniques. Results Immunoassay experiments show that MAbs defining the three melanoma antigens bind to affinity-purified ME491 antigen and inhibit each other from binding in an inhibition radioimmunoassay. Competition immunoprecipitation ex-periments demonstrate that the ME491 and NKI/C-3 antibodies bind to NGA. Rabbit anti-ME491 idiotype serum recognizes determinants shared by NKI/C-3 and the anti-NGA MAbs. A competition immunoprecipitation experiment also confirms the identity of CD63, as defined by MAb RUU-SP 2.28, with the three melanoma antigens. Conclusion These data indicate that the MAGs defined by ME491 and NKI/C-3 as well as the anti-NGA antibodies are epitopes of the same molecule, which is identical to CD63 by both immunochemical and molecular genetic investigations. Implications Our results indicate that the data obtained in studies of these three melanoma antigens may be pooled, and we propose that the molecule recognized by these reagents be classified as CD63. [J Natl Cancer Inst 84:422-429, 1992

Association of maternal serum concentrations of 2,2', 4,4'5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE) levels with birth weight, gestational age and preterm births in Inuit and European populations

<p>Abstract</p> <p>Background</p> <p>Epidemiological studies on the association between maternal exposure to persistent organic pollutants (POPs) and fetal growth alteration report inconsistent findings which weights in favor of additional studies.</p> <p>Methods</p> <p>Blood samples were collected from interviewed pregnant women in Greenland (572), Kharkiv (611) and Warsaw (258) and were analyzed for CB-153 and p,p'-DDE by gas chromatography-mass spectrometry. Data on birth weight, gestational age and preterm birth were obtained for 1322 singleton live births. We examined the association between natural log-transformed serum POPs concentration and birth weight and gestational age using multiple linear regression and the association with prematurity using logistic regression controlling for potential confounding factors.</p> <p>Results</p> <p>The median serum concentrations of CB-153 and p,p'-DDE were for Inuit mothers 105.6 and 298.9, for Kharkiv mothers 27.0 and 645.4 and for Warsaw mothers 10.7 and 365.2 ng/g lipids, respectively. Increase in CB-153 concentration by one unit on the log scale in Inuit mothers serum was associated with significant decrease in infant birth weight of -59 g and gestational age by -0.2 week. Decreases observed in the cohorts in Kharkiv (-10 g and -0.1 week) and in Warsaw (-49 g and -0.2 week) were not statistically significant. Increase in p,p'-DDE concentration by one unit on the log scale was associated with a statistically significant decrease in infant birth weight of -39.4 g and -104.3 g and shortening of gestational age of -0.2 week and -0.6 week in the Inuit and Warsaw cohorts, respectively. In the Kharkiv cohort decrease in birth weight (-30.5 g) was not significant, however a shortening of gestational age of -0.2 week per increase in p,p'-DDE concentration by one unit on the log scale was of the borderline significance. There was no significant association between CB-153 and p,p'-DDE concentrations and risk of preterm birth however, in all cohorts the odds ratio was above 1.</p> <p>Conclusions</p> <p><it>In utero </it>exposure to POPs may reduce birth weight and gestational age of newborns however, new insights as to why results vary across studies were not apparent.</p

In Utero Exposure to Maternal Tobacco Smoke and Subsequent Obesity, Hypertension, and Gestational Diabetes Among Women in The MoBa Cohort

Background: Environmental factors influencing the developmental origins of health and disease need to be identified and investigated. In utero exposure to tobacco smoke has been associated with obesity and a small increase in blood pressure in children; however, whether there is a corresponding increased risk of conditions such as diabetes and hypertension during adulthood remains unclear

In vivo growth of Epstein-Barr virus transformed B cells with mutations in latent membrane protein 2 (LMP2)

 Epstein-Barr virus (EBV) causes infectious mononucleosis in adolescents and is associated with malignant B lymphocyte proliferation in AIDS patients, patients undergoing immune suppression for organ transplantation, and SCID mice. In vitro, EBV transformed, latently infected lymphoblastoid B cell lines (LCLs) contain EBV episomes and express nine virus encoded proteins. Six are nuclear proteins (EBNAs) and three are the integral membrane proteins, LMP1, LMP2A, and LMP2B. To determine if LMP2 was essential for in vivo growth, SCID mice were injected with LCLs containing wild-type EBV (LMP2 + ) or with LCLs transformed with EBV containing mutations in either LMP2A or LMP2B (LMP2 − ). SCID mice injected with the LMP2 + or LMP2 − LCLs were monitored for tumor development, length of time to tumor development, and phenotypic characterization of the resulting tumors. No difference was observed in any of the above parameters between LMP2 + and LMP2 − LCLs demonstrating that LMP2 is not essential for the in vivo growth of EBV transformed B lymphocytes in SCID mice.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42458/1/705-142-4-707_71420707.pd