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621. Functions of GSK-3 Signaling in Development of the Nervous System

Title Tesim:
Functions of GSK-3 Signaling in Development of the Nervous System
Creator:
Kim, Woo-Yang and Snider, William D.
Date of publication:
2011
Abstract Tesim:
Glycogen synthase kinase-3 (GSK-3) is central to multiple intracellular pathways including those activated by Wnt/β-catenin, Sonic Hedgehog, Notch, growth factor/RTK, and G protein-coupled receptor signals. All of these signals importantly contribute to neural development. Early attention on GSK-3 signaling in neural development centered on the regulation of neuronal polarity using in vitro paradigms. However, recent creation of appropriate genetic models has demonstrated the importance of GSK-3 to multiple aspects of neural development including neural progenitor self-renewal, neurogenesis, neuronal migration, neural differentiation, and synaptic development.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/533a-sz03
Identifier:
PMID: 22125510, Publisher DOI: https://doi.org/10.3389/fnmol.2011.00044, Onescience id: 148de122fa5f13c3edda080ce19043334e3e005e, and PMCID: PMC3221276
ISSN:
1662-5099
Journal Title:
Frontiers in Molecular Neuroscience
Journal Volume:
4
Keyword:
GSK-3, synaptic development, Neuroscience, neural differentiation, Review Article, neural progenitor, neuronal migration, and Neural progenitor
Language Label:
English
Person:
Kim, Woo-Yang and Snider, William D.
Rights Statement Label:
In Copyright
Source:
rv0431852

622. Role of MRP transporters in regulating antimicrobial drug inefficacy and oxidative stress-induced pathogenesis during HIV-1 and TB infections

Title Tesim:
Role of MRP transporters in regulating antimicrobial drug inefficacy and oxidative stress-induced pathogenesis during HIV-1 and TB infections
Creator:
Tse-Dinh, Yuk-Ching, Nair, Madhavan, Barber, Paul, Mondal, Debasis, Batrakova, Elena V., and Roy, Upal
Date of publication:
2015
Abstract Tesim:
Multi-Drug Resistance Proteins (MRPs) are members of the ATP binding cassette (ABC) drug-efflux transporter superfamily. MRPs are known to regulate the efficacy of a broad range of anti-retroviral drugs (ARV) used in highly active antiretroviral therapy (HAART) and antibacterial agents used in Tuberculus Bacilli (TB) therapy. Due to their role in efflux of glutathione (GSH) conjugated drugs, MRPs can also regulate cellular oxidative stress, which may contribute to both HIV and/or TB pathogenesis. This review focuses on the characteristics, functional expression, and modulation of known members of the MRP family in HIV infected cells exposed to ARV drugs and discusses their known role in drug-inefficacy in HIV/TB-induced dysfunctions. Currently, nine members of the MRP family (MRP1-MRP9) have been identified, with MRP1 and MRP2 being the most extensively studied. Details of the other members of this family have not been known until recently, but differential expression has been documented in inflammatory tissues. Researchers have found that the distribution, function, and reactivity of members of MRP family vary in different types of lymphocytes and macrophages, and are differentially expressed at the basal and apical surfaces of both endothelial and epithelial cells. Therefore, the prime objective of this review is to delineate the role of MRP transporters in HAART and TB therapy and their potential in precipitating cellular dysfunctions manifested in these chronic infectious diseases. We also provide an overview of different available options and novel experimental strategies that are being utilized to overcome the drug resistance and disease pathogenesis mediated by these membrane transporters.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/nt8c-mj53
Identifier:
PMID: 26441882, Onescience id: 52f429bfd5e253ca5326281e903151cc2a1c9380, PMCID: PMC4585023, and Publisher DOI: https://doi.org/10.3389/fmicb.2015.00948
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
6
Keyword:
HIV-1, therapeutic strategy, QR1-502, TB, Drug Resistance, MRP, Microbiology, antimicrobials, Oxidative Stress, and Pathogenesis
Language Label:
English
Person:
Tse-Dinh, Yuk-Ching, Nair, Madhavan, Barber, Paul, Mondal, Debasis, Batrakova, Elena V., and Roy, Upal
Rights Statement Label:
In Copyright
Source:
8w32rc83g

623. Primer and platform effects on 16S rRNA tag sequencing

Title Tesim:
Primer and platform effects on 16S rRNA tag sequencing
Creator:
Fern, Alison, Woyke, Tanja, Tringe, Susannah G., Kirton, Edward S., Lee, Janey, Tremblay, Julien, Dangl, Jeffery L., Chen, Feng, He, Shaomei, and Singh, Kanwar
Date of publication:
2015
Abstract Tesim:
Sequencing of 16S rRNA gene tags is a popular method for profiling and comparing microbial communities. The protocols and methods used, however, vary considerably with regard to amplification primers, sequencing primers, sequencing technologies; as well as quality filtering and clustering. How results are affected by these choices, and whether data produced with different protocols can be meaningfully compared, is often unknown. Here we compare results obtained using three different amplification primer sets (targeting V4, V6–V8, and V7–V8) and two sequencing technologies (454 pyrosequencing and Illumina MiSeq) using DNA from a mock community containing a known number of species as well as complex environmental samples whose PCR-independent profiles were estimated using shotgun sequencing. We find that paired-end MiSeq reads produce higher quality data and enabled the use of more aggressive quality control parameters over 454, resulting in a higher retention rate of high quality reads for downstream data analysis. While primer choice considerably influences quantitative abundance estimations, sequencing platform has relatively minor effects when matched primers are used. Beta diversity metrics are surprisingly robust to both primer and sequencing platform biases.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/wgfs-e050
Identifier:
PMCID: PMC4523815, Publisher DOI: https://doi.org/10.3389/fmicb.2015.00771, PMID: 26300854, and Onescience id: bfea4257013bd0420530c871dd6e810422ca1273
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
6
Keyword:
CISTI, scientific research, electronic documents, technical reports, technology, Ottawa, NRC, scientific information, science, library, Canada Institute for Scientific and Technical Information, technical literature, National Science Library, research, NSL, NRC-CISTI, and National Research Council Canada
Language Label:
English
Person:
Fern, Alison, Woyke, Tanja, Tringe, Susannah G., Kirton, Edward S., Lee, Janey, Tremblay, Julien, Dangl, Jeffery L., Chen, Feng, He, Shaomei, and Singh, Kanwar
Rights Statement Label:
In Copyright
Source:
5138jn124

624. Pichia pastoris-expressed dengue 3 envelope-based virus-like particles elicit predominantly domain III-focused high titer neutralizing antibodies

Title Tesim:
Pichia pastoris-expressed dengue 3 envelope-based virus-like particles elicit predominantly domain III-focused high titer neutralizing antibodies
Creator:
Swaminathan, Sathyamangalam, Arora, Upasana, Mani, Shailendra, Raut, Rajendra, Poddar, Ankur, de Silva, Aravinda, Tyagi, Poornima, Tripathi, Lav, and Khanna, Navin
Date of publication:
2015
Abstract Tesim:
Dengue poses a serious public health risk to nearly half the global population. It causes ~400 million infections annually and is considered to be one of the fastest spreading vector-borne diseases. Four distinct serotypes of dengue viruses (DENV-1, -2, -3, and -4) cause dengue disease, which may be either mild or extremely severe. Antibody-dependent enhancement (ADE), by pre-existing cross-reactive antibodies, is considered to be the major mechanism underlying severe disease. This mandates that a preventive vaccine must confer simultaneous and durable immunity to each of the four prevalent DENV serotypes. Recently, we used Pichia pastoris, to express recombinant DENV-2 E ectodomain, and found that it assembled into virus-like particles (VLPs), in the absence of prM, implicated in the elicitation of ADE-mediating antibodies. These VLPs elicited predominantly type-specific neutralizing antibodies that conferred significant protection against lethal DENV-2 challenge, in a mouse model. The current work is an extension of this approach to develop prM-lacking DENV-3 E VLPs. Our data reveal that P. pastoris-produced DENV-3 E VLPs not only preserve the antigenic integrity of the major neutralizing epitopes, but also elicit potent DENV-3 virus-neutralizing antibodies. Further, these neutralizing antibodies appear to be exclusively directed toward domain III of the DENV-3 E VLPs. Significantly, they also lack discernible ADE potential toward heterotypic DENVs. Taken together with the high productivity of the P. pastoris expression system, this approach could potentially pave the way toward developing a DENV E-based, inexpensive, safe, and efficacious tetravalent sub-unit vaccine, for use in resource-poor dengue endemic countries.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/35bt-dt29
Identifier:
PMCID: PMC4585145, Onescience id: 40b1e02f578a91610fe7954a67f8128401c20e9d, PMID: 26441930, and Publisher DOI: https://doi.org/10.3389/fmicb.2015.01005
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
6
Keyword:
Antibodies, Neutralizing, Dengue vaccine, Epitopes, neutralizing antibody, Mus musculus, Dengue, Risk, Antibody-Dependent Enhancement, Antibodies, Virus-like particle (VLP), Virion, Serogroup, Immunity, Dengue envelope, Vaccines, Infection, Antibody-dependent enhancement (ADE), and Pichia pastoris
Language Label:
English
Person:
Swaminathan, Sathyamangalam, Arora, Upasana, Mani, Shailendra, Raut, Rajendra, Poddar, Ankur, de Silva, Aravinda, Tyagi, Poornima, Tripathi, Lav, and Khanna, Navin
Rights Statement Label:
In Copyright
Source:
8910k173n

625. Phylogeography, Salinity Adaptations and Metabolic Potential of the Candidate Division KB1 Bacteria Based on a Partial Single Cell Genome

Title Tesim:
Phylogeography, Salinity Adaptations and Metabolic Potential of the Candidate Division KB1 Bacteria Based on a Partial Single Cell Genome
Creator:
Nigro, Lisa M., Hyde, Andrew S., MacGregor, Barbara J., and Teske, Andreas
Date of publication:
2015
Abstract Tesim:
Deep-sea hypersaline anoxic basins (DHABs) and other hypersaline environments contain abundant and diverse microbial life that has adapted to these extreme conditions. The bacterial Candidate Division KB1 represents one of several uncultured groups that has been consistently observed in hypersaline microbial diversity studies. Here we report the phylogeography of KB1, its phylogenetic relationships to Candidate Division OP1 Bacteria, and its potential metabolic and osmotic stress adaptations based on a partial single cell amplified genome (SAG) of KB1 from Orca Basin, the largest hypersaline seafloor brine basin in the Gulf of Mexico. Our results are consistent with the hypothesis – previously developed based on 14C incorporation experiments with mixed-species enrichments from Mediterranean seafloor brines - that KB1 has adapted its proteins to elevated intracellular salinity, but at the same time KB1 apparently imports glycine betaine; this compatible solute is potentially not limited to osmoregulation but could also serve as a carbon and energy source.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/v3va-mn98
Identifier:
PMCID: PMC4993014, Onescience id: f5cb12da65856337d7ab3aa85ccd730e95737bf4, Publisher DOI: https://doi.org/10.3389/fmicb.2016.01266, and PMID: 27597842
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
7
Keyword:
Orca Basin, Genome, Phylogeography, hypersaline, and Candidate Division KB1
Language Label:
English
Person:
Nigro, Lisa M., Hyde, Andrew S., MacGregor, Barbara J., and Teske, Andreas
Rights Statement Label:
In Copyright
Source:
41687q66k

626. Nitric oxide as a regulator of B. anthracis pathogenicity

Title Tesim:
Nitric oxide as a regulator of B. anthracis pathogenicity
Creator:
Espina, Virginia, Vaseghi, Haley, Popov, Serguei G., Liotta, Lance A., Popova, Taissia G., Teunis, Allison, and Zhou, Weidong
Date of publication:
2015
Abstract Tesim:
Nitric oxide (NO) is a key physiological regulator in eukaryotic and prokaryotic organisms. It can cause a variety of biological effects by reacting with its targets or/and indirectly inducing oxidative stress. NO can also be produced by bacteria including the pathogenic Bacillus anthracis; however, its role in the infectious process only begins to emerge. NO incapacitates macrophages by S-nitrosylating the intracellular proteins and protects B. anthracis from oxidative stress. It is also implicated in the formation of toxic peroxynitrite. In this study we further assessed the effects of B. anthracis NO produced by the NO synthase (bNOS) on bacterial metabolism and host cells in experiments with the bNOS knockout Sterne strain. The mutation abrogated accumulation of nitrite and nitrate as tracer products of NO in the culture medium and markedly attenuated growth in both aerobic and microaerobic conditions. The regulatory role of NO was also suggested by the abnormally high rate of nitrate denitrification by the mutant in the presence of oxygen. Anaerobic regulation mediated by NO was reflected in reduced fermentation of glucose by the mutant correlating with the reduced toxicity of bacteria toward host cells in culture. The toxic effect of NO required permeabilization of the target cells as well as the activity of fermentation-derived metabolite in the conditions of reduced pH. The host cells demonstrated increased phosphorylation of major survivor protein kinase AKT correlating with reduced toxicity of the mutant in comparison with Sterne. Our global proteomic analysis of lymph from the lymph nodes of infected mice harboring bacteria revealed numerous changes in the pattern and levels of proteins associated with the activity of bNOS influencing key cell physiological processes relevant to energy metabolism, growth, signal transduction, stress response, septic shock, and homeostasis. This is the first in vivo observation of the bacterial NO effect on the lymphatic system.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/knkh-v073
Identifier:
PMID: 26388860, Onescience id: 30b3177c87119a67a5cada3a614032841990abd3, Publisher DOI: https://doi.org/10.3389/fmicb.2015.00921, and PMCID: PMC4557104
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
6
Keyword:
lymph node, proteome, nitric oxide, anthrax, and nitric oxide synthase
Language Label:
English
Person:
Espina, Virginia, Vaseghi, Haley, Popov, Serguei G., Liotta, Lance A., Popova, Taissia G., Teunis, Allison, and Zhou, Weidong
Rights Statement Label:
In Copyright
Source:
kw52jf955

627. Cultivation-dependent and cultivation-independent characterization of hydrocarbon-degrading bacteria in Guaymas Basin sediments

Title Tesim:
Cultivation-dependent and cultivation-independent characterization of hydrocarbon-degrading bacteria in Guaymas Basin sediments
Creator:
Aitken, Michael D., Gutierrez, Tony, Teske, Andreas, and Biddle, Jennifer F.
Date of publication:
2015
Abstract Tesim:
Marine hydrocarbon-degrading bacteria perform a fundamental role in the biodegradation of crude oil and its petrochemical derivatives in coastal and open ocean environments. However, there is a paucity of knowledge on the diversity and function of these organisms in deep-sea sediment. Here we used stable-isotope probing (SIP), a valuable tool to link the phylogeny and function of targeted microbial groups, to investigate polycyclic aromatic hydrocarbon (PAH)-degrading bacteria under aerobic conditions in sediments from Guaymas Basin with uniformly labeled [13C]-phenanthrene (PHE). The dominant sequences in clone libraries constructed from 13C-enriched bacterial DNA (from PHE enrichments) were identified to belong to the genus Cycloclasticus. We used quantitative PCR primers targeting the 16S rRNA gene of the SIP-identified Cycloclasticus to determine their abundance in sediment incubations amended with unlabeled PHE and showed substantial increases in gene abundance during the experiments. We also isolated a strain, BG-2, representing the SIP-identified Cycloclasticus sequence (99.9% 16S rRNA gene sequence identity), and used this strain to provide direct evidence of PHE degradation and mineralization. In addition, we isolated Halomonas, Thalassospira, and Lutibacterium sp. with demonstrable PHE-degrading capacity from Guaymas Basin sediment. This study demonstrates the value of coupling SIP with cultivation methods to identify and expand on the known diversity of PAH-degrading bacteria in the deep-sea.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/3031-zs72
Identifier:
PMCID: PMC4493657, PMID: 26217326, Publisher DOI: https://doi.org/10.3389/fmicb.2015.00695, and Onescience id: a90685d5b3fff817b2fc8876c4282e7800280056
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
6
Keyword:
Cycloclasticus, hydrocarbon degradation, marine environment, Microbiology, deep sea, QR1-502, Guaymas basin, polycyclic aromatic hydrocarbons (PAHs), and stable isotope probing
Language Label:
English
Person:
Aitken, Michael D., Gutierrez, Tony, Teske, Andreas, and Biddle, Jennifer F.
Rights Statement Label:
In Copyright
Source:
wm117v70f

628. Abundant Intergenic TAACTGA Direct Repeats and Putative Alternate RNA Polymerase β′ Subunits in Marine Beggiatoaceae Genomes: Possible Regulatory Roles and Origins

Title Tesim:
Abundant Intergenic TAACTGA Direct Repeats and Putative Alternate RNA Polymerase β′ Subunits in Marine Beggiatoaceae Genomes: Possible Regulatory Roles and Origins
Creator:
MacGregor, Barbara J.
Date of publication:
2015
Abstract Tesim:
The genome sequences of several giant marine sulfur-oxidizing bacteria present evidence of a possible post-transcriptional regulatory network that may have been transmitted to or from two distantly related bacteria lineages. The draft genome of a Cand. “Maribeggiatoa” filament from the Guaymas Basin (Gulf of California, Mexico) seafloor contains 169 sets of TAACTGA direct repeats and one indirect repeat, with two to six copies per set. Related heptamers are rarely or never found as direct repeats. TAACTGA direct repeats are also found in some other Beggiatoaceae, Thiocystis violascens, a range of Cyanobacteria, and five Bacteroidetes. This phylogenetic distribution suggests they may have been transmitted horizontally, but no mechanism is evident. There is no correlation between total TAACTGA occurrences and repeats per genome. In most species the repeat units are relatively short, but longer arrays of up to 43 copies are found in several Bacteroidetes and Cyanobacteria. The majority of TAACTGA repeats in the Cand. “Maribeggiatoa” Orange Guaymas (BOGUAY) genome are within several nucleotides upstream of a putative start codon, suggesting they may be binding sites for a post-transcriptional regulator. Candidates include members of the ribosomal protein S1, Csp (cold shock protein), and Csr (carbon storage regulator) families. No pattern was evident in the predicted functions of the open reading frames (ORFs) downstream of repeats, but some encode presumably essential products such as ribosomal proteins. Among these is an ORF encoding a possible alternate or modified RNA polymerase beta prime subunit, predicted to have the expected subunit interaction domains but lacking most catalytic residues. A similar ORF was found in the Thioploca ingrica draft genome, but in no others. In both species they are immediately upstream of putative sensor kinase genes with nearly identical domain structures. In the marine Beggiatoaceae, a role for the TAACTGA repeats in translational regulation is suggested. More speculatively, the putative alternate RNA polymerase subunit could be a negative transcriptional regulator.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/qp4c-xd42
Identifier:
PMCID: PMC4679880, PMID: 26733950, Onescience id: 37b461e79f82e7b96fcc8bc64e149a6d9475c4ef, and Publisher DOI: https://doi.org/10.3389/fmicb.2015.01397
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
6
Keyword:
Gene Regulatory Networks, heptamer repeats, Cold Shock Proteins and Peptides, Genome, beta prime subunit, Orange Guaymas "Maribeggiatoa", Carbon, DNA-Directed RNA Polymerases, Binding Sites, DNAJC5, Cyanobacteria, Bacteroidetes, Codon, Initiator, DNA-directed RNA polymerase, Sulfur, Nucleotides, Ribosomal Proteins, Beggiatoaceae, Open Reading Frames, Phosphotransferases, PSMD1, Genes, Repetitive Sequences, Nucleic Acid, and post-transcriptional regulation
Language Label:
English
Person:
MacGregor, Barbara J.
Rights Statement Label:
In Copyright
Source:
vm40z001m

629. Picky, hungry eaters in the cold: persistent substrate selectivity among polar pelagic microbial communities

Title Tesim:
Picky, hungry eaters in the cold: persistent substrate selectivity among polar pelagic microbial communities
Creator:
Steen, Andrew D. and Arnosti, Carol
Date of publication:
2014
Abstract Tesim:
Polar pelagic microbial communities access a narrower range of polysaccharide substrates than communities at lower latitudes. For example, the glucose-containing polysaccharide pullulan is typically not hydrolyzed in fjord waters of Svalbard, even though pullulan is rapidly hydrolyzed in sediments from Svalbard fjords, other polysaccharides are hydrolyzed rapidly in Svalbard waters, and pullulan is hydrolyzed rapidly in temperate waters. The purpose of this study was to investigate potential factors preventing hydrolysis of pullulan in Svalbard fjord waters. To this end, in two separate years, water from Isfjorden, Svalbard, was amended with different carbon sources and/or additional nutrients in order to determine whether increasing the concentration of these potentially-limiting factors would lead to measurable enzymatic activity. Addition of nitrate, phosphate, glucose, or amino acids did not yield detectable pullulan hydrolysis. The only treatment that led to detectable pullulan hydrolysis was extended incubation after the addition of maltotriose (a subunit of pullulan, and potential inducer of pullulanase). In these fjords, the ability to enzymatically access pullulan is likely confined to numerically minor members of the pelagic microbial community. These results are consistent with the hypothesis that pelagic microbial communities at high latitudes exhibit streamlined functionality, focused on a narrower range of substrates, than their temperate counterparts.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/cmen-1075
Identifier:
Onescience id: 574525cd1f493d4a4cf3de1bf4cf75735fecf391, Publisher DOI: https://doi.org/10.3389/fmicb.2014.00527, PMCID: PMC4189390, and PMID: 25339946
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
5
Keyword:
Arctic Ocean, microbial loop, heterotrophic bacteria, latitudinal gradient, and extracellular enzymes
Language Label:
English
Person:
Steen, Andrew D. and Arnosti, Carol
Rights Statement Label:
In Copyright
Source:
gt54kv280

630. Natural oil slicks fuel surface water microbial activities in the northern Gulf of Mexico

Title Tesim:
Natural oil slicks fuel surface water microbial activities in the northern Gulf of Mexico
Creator:
Sweet, Julia, Ziervogel, Kai, Yan, Beizhan, D'Souza, Nigel, and Passow, Uta
Date of publication:
2014
Abstract Tesim:
We conducted a series of roller tank incubations with surface seawater from the Green Canyon oil reservoir, northern Gulf of Mexico, amended with either a natural oil slick (GCS-oil) or pristine oil. The goal was to test whether bacterial activities of natural surface water communities facilitate the formation of oil-rich marine snow (oil snow). Although oil snow did not form during any of our experiments, we found specific bacterial metabolic responses to the addition of GCS-oil that profoundly affected carbon cycling within our 4-days incubations. Peptidase and β-glucosidase activities indicative of bacterial enzymatic hydrolysis of peptides and carbohydrates, respectively, were suppressed upon the addition of GCS-oil relative to the non-oil treatment, suggesting that ascending oil and gas initially inhibits bacterial metabolism in surface water. Biodegradation of physically dispersed GCS-oil components, indicated by the degradation of lower molecular weight n-alkanes as well as the rapid transformation of particulate oil-carbon (C: N >40) into the DOC pool, led to the production of carbohydrate- and peptide-rich degradation byproducts and bacterial metabolites such as transparent exopolymer particles (TEP). TEP formation was highest at day 4 in the presence of GCS-oil; in contrast, TEP levels in the non-oil treatment already peaked at day 2. Cell-specific enzymatic activities closely followed TEP concentrations in the presence and absence of GCS-oil. These results demonstrate that the formation of oil slicks and activities of oil-degrading bacteria result in a temporal offset of microbial cycling of organic matter, affecting food web interactions and carbon cycling in surface waters over cold seeps.
Resource type:
Article
Deposit Record:
http://windsor.libint.unc.edu:8181/fcrepo/rest/prod/f8/ca/d5/63/f8cad563-9b67-4053-a6f6-f544764d92b7
Type:
http://purl.org/dc/dcmitype/Text
DOI:
https://doi.org/10.17615/yvyy-d542
Identifier:
Onescience id: f49ad1d278b7c0ae2c460b0c305eca62f57e141c, PMCID: PMC4021148, PMID: 24847314, and Publisher DOI: https://doi.org/10.3389/fmicb.2014.00188
ISSN:
1664-302X
Journal Title:
Frontiers in Microbiology
Journal Volume:
5
Keyword:
enzyme activities, carbon cycle, GC600, Gulf of Mexico, oil snow, TEP, and oil slick
Language Label:
English
Person:
Sweet, Julia, Ziervogel, Kai, Yan, Beizhan, D'Souza, Nigel, and Passow, Uta
Rights Statement Label:
In Copyright
Source:
fx719t59c