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The naturally occurring ectoparasite salmon lice (Lepeophtherirus salmonis) poses a great challenge for the salmon farming industry, as well as for wild salmonids in the Northern hemisphere. To better control the infestation pressure and protect the production, there is a need to provide fish farmers with sensitive and efficient tools for rapid early detection and monitoring of the parasitic load. This can be achieved by targeting L. salmonis DNA in environmental samples. Here, we developed and tested a new L. salmonis specific DNA-based assay (qPCR assay) for detection and quantification from seawater samples using an analytical pipeline compatible with the Environmental Sample Processor (ESP) for autonomous water sample analysis of gene targets. Specificity of the L. salmonis qPCR assay was demonstrated through in-silico DNA analyses covering sequences of different L. salmonis isolates. Seawater was spiked with known numbers of nauplii and copepodite free-swimming (planktonic) stages of L. salmonis to investigate the relationship with the number of marker gene copies (MGC). Finally, field samples collected at different times of the year in the vicinity of a salmon production farm in Western Norway were analyzed for L. salmonis detection and quantification. The assay specificity was high and a high correlation between MGC and planktonic stages of L. salmonis was established in the laboratory conditions. In the field, L. salmonis DNA was consequently detected, but with MGC number below that expected for one copepodite or nauplii. We concluded that only L. salmonis tissue or eDNA residues were detected. This novel study opens for a fully automatized L. salmonis DNA quantification using ESP robotic to monitor the parasitic load, but challenges remain to exactly transfer information about eDNA quantities to decisions by the farmers and possible interventions. [ABSTRACT FROM AUTHOR]

Cold-water coral (CWC) reefs are numerous and widespread along the Norwegian continental shelf where oil and gas industry operate. Uncertainties exist regarding their impacts from operational discharges to drilling. Effect thresholds obtained from near-realistic exposure of suspended particle concentrations for use in coral risk modeling are particularly needed. Here, nubbins of Desmophyllum pertusum (Lophelia pertusa) were exposed shortly (5 days, 4h repeated pulses) to suspended particles (bentonite BE; barite BA, and drill cuttings DC) in the range of ~ 4 to ~ 60 mg.l-1 (actual concentration). Physiological responses (respiration rate, growth rate, mucus-related particulate organic carbon OC and particulate organic nitrogen ON) and polyp mortality were then measured 2 and 6 weeks post-exposure to assess long-term effects. Respiration and growth rates were not significantly different in any of the treatments tested compared to control. OC production was not affected in any treatment, but a significant increase of OC:ON in mucus produced by BE-exposed (23 and 48 mg.l-1) corals was revealed 2 weeks after exposure. Polyp mortality increased significantly at the two highest DC doses (19 and 49 mg.l-1) 2 and 6 weeks post-exposure but no significant difference was observed in any of the other treatments compared to the control. These findings are adding new knowledge on coral resilience to short realistic exposure of suspended drill particles and indicate overall a risk for long-term effects at a threshold of ~20 mg.l-1. [ABSTRACT FROM AUTHOR]

Knowledge of key species sensitivity for oil spill response (OSR) options is needed to support decision-making and mitigate impact on sensitive life stages of keystone species. Here, Northern shrimp (Pandalus borealis) larvae were exposed for 24 h to a gradient (H-High, M-Medium: 10 times dilution and L-Low: 100 times dilution) of mechanically- (MDO) (H < 6 mg/L total hydrocarbon content) and chemically- (CDO) dispersed oil (Slickgone NS, H < 20 mg/L total hydrocarbon content), followed by a recovery period. Larval mortality, feeding rate and development were evaluated. Overall, the results show that 24 h exposure to field-realistic concentrations of CDO lead to lower survival, reduced feeding rate and slower larval development in P. borealis larvae compared to MDO. These effects persisted during recovery, indicating a higher vulnerability with dispersant use and the need for longer observation periods post-exposure to fully evaluate the consequences for sensitive life-stages from OSR. • 24 h oil exposure with dispersant (CDO) is more detrimental to northern shrimp larvae than oil only (MDO). • Mortality in high CDO at exposure, and in all concentrations of CDO during recovery • Reduced feeding and delayed development predominant in CDO • Inclusion of recovery warranted in environmental risk analysis from oil spill clean-up • Study relevant for prioritization of oil spill response decisions [ABSTRACT FROM AUTHOR]

This study aimed at providing confidence in the predictability of the impacts of drill cuttings (DC) discharge on the cold-water coral Lophelia pertusa. L. pertusa was exposed to DC from offshore exploration in the lab with the goal to assess precautionary thresholds of effects. Two exposure scenarios with DC were tested: a long-term (LT) pulsed exposure (12 weeks, peak concentrations: 2-50 mg/L, mean concentrations: 1-25 mg/L) and a short-term (ST) continuous exposure (2.5 weeks, mean concentrations: 4-42 mg/L). After exposure, a recovery period of 16 and 4 weeks was maintained in LT and ST, respectively. While there was an assumption that DC might result in an increase in respiration, decrease in growth, enhanced mucus production, reduced fatty acid content, only a significant rise was noted in skeleton growth at DC 4 mg/L and a significant increase of mucus particulate organic carbon at 25 mg/L at end of the exposure. DC did not markedly reduce prey capture rate consecutive to DC exposure. However, the effect of DC produced an increase of coral polyp activity during exposure and a return to pre-exposure conditions after cessation of DC, and coenosarc was smothered from DC even after a long recovery period (4 weeks). Overall, a DC concentration of 10 mg/L seems to represent a threshold above which changes in coral conditions were observed however with no apparent physiological consequences for the coral within the experimental time scale. [ABSTRACT FROM AUTHOR]

Despite the importance of the cold-water coralLophelia pertusato deep-sea reef ecosystem functioning, current knowledge of key physiological responses to available food resources is scarce. Scenarios with varying food density may help to understand how corals deal with seasonal variations in the dark ocean and might be used to study consequences of anthropogenic activities potentially affecting food availability. Thus, the physiological responses ofL. pertusato varying food (Artemia salinanauplii) concentration, ranging from 20% to 300% of carbon equivalent turned over by basal coral respiration, were investigated. A starvation group was also included. Measurements of respiration, growth, mucus production, and energy reserves (storage fatty acids) were performed at several time intervals over 26 weeks. In general, data showed a stronger effect of experimental time on measured responses, but no significant influence of food density treatment. In starved corals, respiration rate declined to 52% of initial respiration, while skeleton growth rate was maintained at the same rate asArtemia-fed corals throughout the investigation. Mucus production measured as the sum of dissolved organic carbon (DOC) and particulate organic carbon (POC) was also similar across food treatments, but POC production exceeded that of DOC at the highest food density. No marked effect was observed on storage fatty acids. These results confirm thatL. pertusais highly resilient to environmental conditions with suboptimal food densities over a time scale of months. Regulation of several physiological processes, including respiration and mucus production, possibly in combination with an opportunistic feeding strategy, contributed to this tolerance to maintain viable corals. Thus, it appears thatL. pertusais well adapted to life in the deep sea. [ABSTRACT FROM AUTHOR]

For the environmental monitoring of coral, mucus appears to be an appropriate biological matrix due to its array of functions in coral biology and the non-intrusive manner in which it can be collected. The aim of the present study was to evaluate the feasibility of using mucus of the stony coralLophelia pertusa (L. pertusa)as an analytical matrix for discovery of biomarkers used for environmental monitoring. More specifically, to assess whether a mass-spectrometry-based proteomic approach can be applied to characterize the protein composition of coral mucus and changes related to petroleum discharges at the seafloor. Surface-enhanced laser desorption/ionization–time of flight mass spectrometry (SELDI-TOF MS) screening analyses of orange and whiteL. pertusashowed that the mucosal protein composition varies significantly with color phenotype, a pattern not reported prior to this study. Hence, to reduce variability from phenotype difference,L. pertusawhite individuals only were selected to characterize in more detail the basal protein composition in mucus using liquid chromatography, mass spectrometry, mass spectrometry (LC-MS/MS). In total, 297 proteins were identified inL. pertusamucus of unexposed coral individuals. Individuals exposed to drill cuttings in the range 2 to 12 mg/L showed modifications in coral mucus protein composition compared to unexposed corals. Although the results were somewhat inconsistent between individuals and require further validation in both the lab and the field, this study demonstrated preliminary encouraging results for discovery of protein markers in coral mucus that might provide more comprehensive insight into potential consequences attributed to anthropogenic stressors and may be used in future monitoring of coral health. [ABSTRACT FROM PUBLISHER]

Lophelia pertusa is the dominant reef-building organism of cold-water coral reefs, and is known to produce significant amounts of mucus, which could involve an important metabolic cost. Mucus is involved in particle removal and feeding processes, yet the triggers and dynamics of mucus production are currently still poorly described because the existing tools to study these processes are not appropriate. Using a novel microscopic technique—digital holographic microscopy (DHM)–we studied the mucus release of L. pertusa under various experimental conditions. DHM technology permits μm-scale observations and allows the visualization of transparent mucoid substances in real time without staining. Fragments of L. pertusa were first maintained in flow-through chambers without stressors and imaged with DHM, then exposed to various stressors (suspended particles, particulate food and air exposure) and re-imaged. Under non-stressed conditions no release of mucus was observed, whilst mucus strings and sheaths were produced in response to suspended particles (activated charcoal and drill cuttings sediment) i.e. in a stressed condition. Mucus strings and so-called ‘string balls’ were also observed in response to exposure to particulate food (brine shrimp Artemia salina). Upon air-exposure, mucus production was clearly visible once the fragments were returned to the flow chamber. Distinct optical properties such as optical path length difference (OPD) were measured with DHM in response to the various stimuli suggesting that different mucus types are produced by L. pertusa. Mucus produced to reject particles is similar in refractive index to the surrounding seawater, suggesting that the energy content of this mucus is low. In contrast, mucus produced in response to either food particle addition or air exposure had a higher refractive index, suggesting a higher metabolic investment in the production of these mucoid substances. This paper shows for the first time the potential of DHM technology for the detection, characterization and quantification of mucus production through OPD measurements in L. pertusa. [ABSTRACT FROM AUTHOR]

Oil spill clean-up measures using in situ burning can potentially result in seafloor contamination affecting benthic organisms. To mimic realistic exposure and measure effects, ovigerous Northern shrimp were continuously exposed for two weeks to the water-soluble fraction of oil coated on gravel followed by two weeks in clean seawater. North Sea crude oil (NSC) and field generated in situ burn residue (ISBR) of NSC were used (Low: 3 g/kg gravel, Medium: 6 g/kg gravel and High: 12 g/kg gravel). The concentrations of polyaromatic hydrocarbons (PAHs) in the water resulting from NSC were higher compared to ISBR. No mortality was observed in any treatment and overall moderate sublethal effects were found, mostly after exposure to NSC. Feeding was temporarily reduced at higher concentrations of NSC. PAH levels in hepatopancreas tissue were significantly elevated following exposure and still significantly higher at the end of the experiment in NSC High and ISBR High compared to control. Mild inflammatory response reactions and tissue ultrastructural alterations in gill tissue were observed in both treatments. Signs of necrosis occurred in ISBR High. No change in shrimp locomotory activity was noted from NSC exposure. However, ISBR exposure increased activity temporarily. Larvae exposed as pleopod-attached embryos showed significant delay in development from stage I to stage II after exposure to NSC High. Based on this study, oil-contaminated seafloor resulting from in situ burning clean-up actions does not appear to cause serious effects on bottom-living shrimp. [Display omitted] • Comparative toxicity of crude oil and field generated in situ burn residue (ISBR). • Oil and ISBR: No mortality, but minor gill damage also 2 weeks post-exposure. • Oil and ISBR: Elevated tissue levels of PAHs, also 2 weeks post-exposure. • Oil only: Transient reduction of adult feeding rate and delayed larval development. • ISBR less adverse effects than crude oil. [ABSTRACT FROM AUTHOR]

Ocean acidification (OA) resulting from anthropogenic emissions of carbon dioxide (CO2) has already lowered and is predicted to further lower surface ocean pH. There is a particular need to study effects of OA on organisms living in cold-water environments due to the higher solubility of CO2 at lower temperatures. Mussel larvae (Mytilus edulis) and shrimp larvae (Pandalus borealis) were kept under an ocean acidification scenario predicted for the year 2100 (pH 7.6) and compared against identical batches of organisms held under the current oceanic pH of 8.1, which acted as a control. The temperature was held at a constant 10°C in the mussel experiment and at 5°C in the shrimp experiment. There was no marked effect on fertilization success, development time, or abnormality to the D-shell stage, or on feeding of mussel larvae in the low-pH (pH 7.6) treatment. Mytilus edulis larvae were still able to develop a shell in seawater undersaturated with respect to aragonite (a mineral form of CaCO3), but the size of low-pH larvae was significantly smaller than in the control. After 2 mo of exposure the mussels were 28% smaller in the pH 7.6 treatment than in the control. The experiment with Pandalus borealis larvae ran from 1 through 35 days post hatch. Survival of shrimp larvae was not reduced after 5 wk of exposure to pH 7.6, but a significant delay in zoeal progression (development time) was observed. [ABSTRACT FROM AUTHOR]

Biomarkers are widely used to measure environmental impacts on marine species. For many biomarkers, it is not clear how the signal levels relate to effects on the whole organism. This paper shows how species sensitivity distributions (SSDs) can be applied to evaluate multiple biomarker responses in species assemblages. To our knowledge, the present study compared for the first time SSDs based on biomarker response levels for marine species to a SSD for whole-organism responses. The comparison indicates that for exposure to dispersed oil in the marine environment, the selected biomarkers were, on average, 35- to 50-fold more sensitive than the whole-organism effect. At the 5% hazardous concentration derived from the SSD for whole-organism effects, which is a conservative threshold level, the potentially affected fraction of species showing biomarker response corresponds to approximately 80%. Variation in species sensitivity, expressed either as biomarker or as whole-organism response levels, were similar. Although uncertainties exist, the link between biomarkers and risk assessment presented here provides a preliminary guideline for deciding when biomarker responses likely are hazardous and, therefore, require further investigation. [ABSTRACT FROM AUTHOR]

The sensitivity of different tissues for assessment of chronic low-dose environmental exposure of fish to alkylphenols (APs) was investigated. We exposed Atlantic cod (Gadus morhua) in the laboratory to tritium labelled 4-tert-butylphenol, 4n-pentylphenol, 4n-hexylphenol, and 4n-heptylphenol via seawater (8ng/l) and via contaminated feed (5μg/kg fish per day). Measurements of different fish tissues during eight days of exposure and eight subsequent days of recovery revealed that APs administered via spiked seawater were readily taken up whereas the uptake was far less efficient when APs were administered in spiked feed. AP residues were mainly located in the bile fluid whereas the concentrations in liver were very low, indicating a rapid excretion and the liver–bile axis to be the major route of elimination. The biological half-life of APs in the exposed cod was short, between 10 and 20h. Our study shows that in connection with biomonitoring of AP exposure in fish, assessment of AP metabolites in bile fluid is a more sensitive tool than detection of parent AP levels in liver or other internal tissues. [Copyright &y& Elsevier]

This article deals with the development and novel application of an amperometric peroxidase biosensor for monitoring fish exposure to petroleum-related discharges, in particular, to alkyl phenols (AP) using fish bile as the main sample material. The biosensor consisted of a screen-printed electrode coupled with peroxidase immobilized by glutaraldehyde cross-linking. The sensor was optimized with regards to factors such as immobilization procedures, substrate selectivity, and matrix effects. The biosensor was used for the analysis of fish bile samples from Atlantic cod (Gadus morhua L.) exposed in the laboratory during a 2 week period to different petroleum related compounds. The biosensor could distinguish between bile samples of fish exposed to water containing high concentrations (a mixture of C4–C7) to moderate levels (mainly C0–C5) of alkylphenols and that of the control group. [ABSTRACT FROM AUTHOR]

The scientific goal of the present work is the development of a new molecular biomarker as a biomonitoring tool for early assessment of the biological effect of complex mixtures of pollutants (especially polycyclic aromatic hydrocarbons) and validation of the approach by comparison with standard methodologies. Hence, a DNA‐based biosensor, which is able to detect the presence of compounds with affinity for DNA to measure their effect on the guanine base, was used in this research. [ABSTRACT FROM AUTHOR]

Sheepshead minnows (Cyprinodon variegatus) were continuously exposed to two concentrations of polycyclic aromatic hydrocarbons (PAHs) dissolved in seawater (Σ PAH 5 7.57 and 72.31 µg/L) for 36 d, followed by 8 d of depuration. The PAHs studied were naphthalene (NPH or C0-NPH), phenanthrene (PHE or C0-PHE), pyrene (PYR), 2-methylnaphthalene (C1-NPH), 1,3-dimethylnaphthalene (C2-NPH), 2-isopropylnaphthalene (C3-NPH), 9-methylphenanthrene (C1-PHE), and 9-ethylphenanthrene (C2-PHE). Uptake rate constants (k1 ) for NPHs increased with increasing degree of alkylation and log value of the octanol/water partition coefficient (Kow), whereas k1 values for three- and four-ring PAHs were lower despite their high log Kow values. Elimination rate constants (k2) for the homologue series of NPHs and PHEs generally increased with decreasing degree of alkylation and log Kow values. However, the depuration time did not directly correlate with the molecular size for nonalkylated PAHs. Bioconcentration factors (BCFs) were estimated from the ratio of k1 to k2 and also directly from PAH concentrations in fish tissue and water samples, and the factors generated by the two methods were very similar. A significant positive correlation was determined between log BCFs and log Kow values for the series of C0 - through C3-NPH at both low (r² = 0.985, p = 0.0077) and high (r² = 0.956, p = 0.022) exposures, although this correlation was not determined for all the PAHs studied. As a result of increased metabolism and/ or reduced bioavailability with increasing lipophilic character, the estimated BCFs for C0 - through C2-PHE and PYR were generally lower than those for C0- through C3-NPH. The two exposure levels revealed minor variations... [ABSTRACT FROM AUTHOR]

Within the frame of a large environmental study, we report on a research program that investigated the potential for bioaccumulation and subsequent effect responses in several marine organisms exposed to chronic levels of dispersed crude oil. Body burden can be estimated from kinetic parameters (rate constants for uptake and elimination), and appropriate body burden--effect relationships may improve assessments of environmental risks or the potential for such outcomes following chronic discharges at sea. We conducted a series of experiments in a flow-through system to describe the bioaccumulation kinetics of polycyclic aromatic hydrocarbons (PAH) at low concentrations of dispersed crude oils. Mussels (Mytilus edulis) and juvenile turbot (Scophthalmus maximus) were exposed for periods ranging from 8 to 21 d. Postexposure, the organisms were kept for a period of 9 to 10 d in running seawater to study elimination processes. Rate constants of uptake (k1) and elimination (k2) of the PAHs during and following exposure were calculated using a first-order kinetic model that assumed a decrease of the substances in the environment over time. The estimated bioconcentration factor was calculated from the ratio of k1/k2. The kinetic parameters of two-, three-, and four-ring PAHs in mussel and fish are compared with estimates based on hydrophobicity alone, expressed by the octanol-water partition coefficient, Kow (partitioning theory). A combination of reduced bioavailability of PAHs from oil droplets and degradation processes of PAHs in body tissues seems to explain discrepancies between kinetic rates based on Kow and actual kinetic rates measured in fish. Mussels showed a pattern more in compliance with the partitioning theory. [ABSTRACT FROM AUTHOR]

Assessing the fate in marine biota of hydrocarbons derived from oil particles that are discharged during exploration and production is of relevant environmental concern. However, a rather complex experimental setup is required to carry out such investigations. In this study, a sophisticated tool, the continuous-flow system (CFS), was used to mimic dispersed oil exposure to marine biota. Polycyclic aromatic hydrocarbon (PAH) uptake was studied in two species, the blue mussel Mytilus edulis and juvenile of the turbot Scophthalmus maximus, and in semipermeable membrane devices (SPMD) exposed to crude oil dispersed in a flow-through system. After an exposure period of 8 to 21 d, elimination in organisms and devices was analyzed for 9 to 10 d following transfer to PAH-free seawater. Principal component analysis (PCA) revealed different PAH patterns. In mussel and SPMD, the PAH profiles were very close to that analyzed in seawater. Slight differences were, however, indicated for large molecules with log Kow above six. Nonachievement of steady-state concentration and bioavailability of PAH in oil droplets may account for these differences. The PAH composition in fish revealed only congeners with two to three aromatic rings. A combination of bioavailability and efficient metabolism of the larger PAH molecules may explain this pattern. The CFS made possible a better understanding of some critical factors governing bioconcentration in marine biota from dispersed oil. Yet the results illustrate that uptake of PAH from exposure to oil particles is complex and that different species may bioconcentrate different molecules depending on factors like life style and metabolic capability to degrade the potential harmful substances. Hence, risk assessment of the actual impact of discharges to marine biota should consider these essential biological and ecological factors. [ABSTRACT FROM AUTHOR]

We analyzed the interaction between a bacterial cell wall protein and dendritic cells (DCs). Outer membrane protein A from Klebsiella pneumoniae (kpOmpA) specifically bound to professional antigen presenting cells and was endocytosed by immature DCs via a receptor-dependent mechanism. kpOmpA signaled through Toll-like receptor 2, induced DCs to produce interleukin 12 and induced maturation of DCs. Whole antigen that was coupled to kpOmpA and injected into mice was taken up by DCs and delivered to the conventional cytosolic MHC class I presentation pathway. kpOmpA also primed antigen-specific CD8+ CTLs in the absence of CD4+ T cell help or adjuvant and elicited therapeutic immunity to antigen-expressing tumors. Thus, OmpA belongs to a class of proteins that are able to elicit CTL responses to exogenous antigen. [ABSTRACT FROM AUTHOR]

A mixture of sialylglycoasparagines and sialylglycopeptides was successively incubated with lysosomal extracts. at two pH values, first at pH 7.5 and then at pH 4. The ¹H-NMR analysis of the sialyloligosaccharides released during the enzymatic digestion demonstrates the sequential action of aspartylgiucosaminidase and an endo-N- acetyl-β-D-glucosaminidase which release sialyloligosaccharides identical to the reference sugars isolated from the urine of patients suffering from sialidosis. This process represents a new catabolic pathway for N-glycosyl-proteins which may account for the appearance of the oligosaccharides stored in tissues and urine of patients suffering from lysosomal diseases. [ABSTRACT FROM AUTHOR]

Characterizes an endo-N-acetyl-beta-D-glucosaminidase, active towards oligosaccharides, in rat liver. Determination of reaction product's primary structure through nuclear magnetic resonance spectroscopy; Location of enzyme in the lysomal fraction; Absence of enzyme reaction to conjugated glycans; Evidence of alternative pathways for the degradation of glycoprotein glycans inside lysosomes; Speculation of enzymic activity as oligosaccharide origin.

Klebsiella pneumoniae OmpA, the 40-kDa major protein of the outer membrane, was cloned and expressed in Escherichia coli. The recombinant protein was produced intracellularly in E. coli as inclusion bodies. Fusion of a short peptide to the N-terminus of native P40 facilitated high-level expression of the recombinant protein. Purified recombinant P40 was analyzed to verify purity and structural integrity. The molecular mass of purified recombinant P40 determined by electrospray mass spectrometry was 37 061 Da, in agreement with the theoretical mass deduced from the DNA sequence. Specific proliferation of recombinant-P40-primed murine lymph node cells in response to recombinant P40 stimulation in vitro indicated the presence of a T-cell epitope on recombinant P40. The induction of high serum antibody titers to a synthetic peptide derived from the attachment protein G of the respiratory syncytial virus when chemically coupled to recombinant P40 indicated that the protein had potent carrier properties. [ABSTRACT FROM AUTHOR]

A panel of 16 monoclonal antibodies (mAb) were produced against rat T-kininogen to characterize this family of proteins. These mAbs bound 125I-T-kininogen by radioimmunoassay as well as reacting strongly with immobilized T-kininogen in an enzyme-linked immunosorbent assay (ELISA). The reactivity of these antibodies with proteolytic fragments of T-kininogen demonstrated the recognition of several different epitopes. One antibody was specific for the domain I of the heavy chain and/or the light chain, twelve antibodies were specific for domain 2 and three antibodies were specific for domain 3. All monoclonal antibodies recognized the two forms of T-kininogen encoded by the two different T-kininogen genes. T1 and TII kininogen, except antibody TK 16-3.1 which uniquely reacted with TII kininogen. Two antibodies recognizing domain 2 cross-reacted with the high-molecular-mass kininogen (H-kininogen), whereas all the other monoclonal antibodies were specific to T-kininogen and did not recognize the heavy chain of H-kininogen. None of the antibodies tested altered the thiol protease inhibitory activity of T-kininogen, its partial proteolysis by rat mast cell chymase or the hydrolysis of H-kininogen by rat urinary kallikrein. The use of these antibodies in the development of sensitive ELISA to measure T-kininogen levels in plasma, urine, liver microsomes and hepatocytes is described. Two different forms of T-kininogen were distinguished by these monoclonal antibodies in Western blotting using rat plasma. The localization of T-kininogen was defined using these monoclonal antibodies by immunohistochemistry in rat liver hepatocytes and rat kidney. [ABSTRACT FROM AUTHOR]

Submaxillary gland extracts have been fractionated to characterize the enzyme responsible for the T-kininogenase activity previously reported in this tissue [Damas, J. & Adam, A. (1985) Mol. Physiol 8, 307316] and to know whether this activity could be of physiological relevance, since no enzyme reacting in catalytic amounts has been described so far to be able to release a vasoactive peptide from T-kininogen. The purified enzyme, provisionally called endopeptidase K, has an apparent Mr of 27 000 when not reduced prior to analysis but 21 000 after reduction and an acidic pi of 4.3 ± 0.1. Antigenically, it is not related to tissue kallikrein. Upon incubation with purified T-kininogen it may induce a complete liberation of T-kinin from the precursor provided it is added in stoichiometric amounts. However, in parallel with the liberation of immunoreactive kinin, a proteolysis of T-kininogen is observed which is not restricted to the site of insertion of T-kinin as would be expected using a specific kininogenase. In agree-ment with these results, no change of the mean blood pressure was observed upon injection of endopeptidase K into the circulation of normal rats even if the amount of injected enzyme was up to ten times that required for tissue kallikrein to induce a significant fall in blood pressure. However, in spite of the large proteolysis induced by incubation with stoichiometric amounts of endopeptidase K, the total papain inhibiting capacity of T-kininogen as well as the value of the apparent inhi-bition constant, Ki, with this proteinase remained unchanged. Prote-olytic fragments which retain cysteine-proteinase-inhibiting activity may therefore be released from T-kininogen by endopeptidase K more easily than immunoreactive kinin, thus emphasizing a prominent function of proteinase inhibitor or of proteinase inhibitor precursor for this molecule. [ABSTRACT FROM AUTHOR]

The use of natural marine bacteria as "oil sensors" for the detection of pollution events can be suggested as a novel way of monitoring oil occurrence at sea. Nucleic acid-based devices generically called genosensors are emerging as potentially promising tools for in situ detection of specific microbial marker genes suited for that purpose. Functional marker genes are particularly interesting as targets for oil-related genosensing but their identification remains a challenge. Here, seawater samples, collected in tanks with oil addition mimicking a realistic oil spill scenario, were filtered and archived by the Environmental Sample Processor (ESP), a fully robotized genosensor, and the samples were then used for post-retrieval metatranscriptomic analysis. After extraction, RNA from ESP-archived samples at start, Day 4 and Day 7 of the experiment was used for sequencing. Metatranscriptomics revealed that several KEGG pathways were significantly enriched in samples exposed to oil. However, these pathways were highly expressed also in the non-oil-exposed water samples, most likely as a result of the release of natural organic matter from decaying phytoplankton. Temporary peaks of aliphatic alcohol and aldehyde dehydrogenases and monoaromatic ring-degrading enzymes (e.g., ben, box, and dmp clusters) were observed on Day 4 in both control and oil-exposed and non-exposed tanks. Few alkane 1-monooxygenase genes were upregulated on oil, mostly transcribed by families Porticoccaceae and Rhodobacteraceae, together with aromatic ring-hydroxylating dioxygenases, mostly transcribed by Rhodobacteraceae. Few transcripts from obligate hydrocarbonoclastic genera of Alcanivorax, Oleispira and Cycloclasticus were significantly enriched in the oil-treated exposed tank in comparison to control the non-exposed tank, and these were mostly transporters and genes involved in nitrogen and phosphorous acquisition. This study highlights the importance of seasonality, i.e., phytoplankton occurrence and senescence leading to organic compound release which can be used preferentially by bacteria over oil compounds, delaying the latter process. As a result, such seasonal effect can reduce the sensitivity of genosensing tools employing bacterial functional genes to sense oil. A better understanding of the use of natural organic matter by bacteria involved in oil-biodegradation is needed to develop an array of functional markers enabling the rapid and specific in situ detection of anthropogenic pollution. [ABSTRACT FROM AUTHOR]

The application of chemical dispersants is one option of oil spill response (OSR). Here, Northern shrimp (Pandalus borealis) larvae were experimentally exposed for short periods (6 h and 1 h) to a realistic concentration of chemically dispersed oil (CDO) (~10 mg L−1 THC), mechanically dispersed oil (MDO) (~7 mg L−1 THC), and dispersant only (D). A control (C) with seawater served as reference. Short-term effects on survival and feeding were examined right after exposure and longer-term consequences on survival, feeding, growth and development following 30 days of recovery. Both exposure durations provoked long lasting effects on larval fitness, with 1 h exposure leading to minor effects on most of the selected endpoints. The 6 h exposure affected all endpoints with more adverse impacts after exposure to CDO. This study provides important data for assessing the best OSR option relevant to NEBA (Net Environmental Benefit Analysis). • Short- and long-term effects of oil spill response on shrimp larvae • Field-realistic concentrations of oil and chemical dispersant • Long lasting effects of short exposure (6 h and 1 h) on larvae fitness parameters • Addition of chemical dispersant increases short- and long-term adverse effects of oil. • Contribution to NEBA decision-frameworks for reaction and mitigation [ABSTRACT FROM AUTHOR]

A portable surface plasmon resonance (SPR) instrument was tested for the first time for the detection of oligonucleotide sequences derived from the 16S rRNA gene of Oleispira antarctica RB-8, a bioindicator species of marine oil contamination, using morpholino-functionalized sensor surfaces. We evaluated the stability and specificity of morpholino coated sensor surfaces and tested two signal amplification regimes: (1) sequential injection of sample followed by magnetic bead amplifier and (2) a single injection of magnetic bead captured oligo. We found that the sensor surfaces could be regenerated for at least 85 consecutive sample injections without significant loss of signal intensity. Regarding specificity, the assay clearly differentiated analytes with only one or two mismatches. Signal intensities of mismatch oligos were lower than the exact match target at identical concentrations down to 200 nM, in standard phosphate buffered saline with 0.1 % Tween-20 added. Signal amplification was achieved with both strategies; however, significantly higher response was observed with the sequential approach (up to 16-fold), where first the binding of biotin-probe-labeled target oligo took place on the sensor surface, followed by the binding of the streptavidin magnetic beads onto the immobilized targets. Our experiments so far indicate that a simple coating procedure in combination with a relatively cost-efficient magnetic-bead-based signal amplification will provide robust SPR based nucleic acid sensing down to 0.5 nM of a 45-nucleotide long oligo target (7.2 ng/mL). [ABSTRACT FROM AUTHOR]

Today's benthic offshore biological monitoring of oil & gas (O&G) activities relies on macrofauna taxa enumeration. For the future, analysis of DNA isolated directly from sediments holds great potential for multi-trophic biodiversity surveys and the monitoring of a larger spectrum of benthic taxa, including micro-fauna. Here, we evaluate more specifically the potential of microfauna-specific gene quantification in relation to both petroleum-related discharge compounds and other seafloor environmental properties. We carried out this evaluation using sediment samples collected at drilling Region III on the Norwegian continental shelf where DNA metabarcoding of eukaryotic diversity was already performed. Generally, the quantification of microfauna indicator taxa related well to the gradient of contamination on the seafloor. Contrary to eukaryotic Euplotida , metabarcoding data and qPCR numbers for indicative prokaryotic taxa showed the same relationship to offshore contaminants (both showed positive relationship). We found absolute numbers of SSU rRNA gene copies of (1) Dinophyceae , Bacillariophyceae and Alcanivorax were correlated with the level of petroleum-related compounds but not with other environmental variables, (2) bacteria closely related to Shewanella were correlated with the concentration of Ba, PAH, as well to percent of gravel, (3) Desulfobacteriales correlated with petroleum-related contaminants, but as well with percent of gravel and grain size. Findings from our study suggest that biomonitoring surveys of O&G activities on benthos could benefit from quantification of specific micro-fauna indicators that is simpler and faster than the methods currently used for impact assessment of benthos. Unlabelled Image • Metabarcoding provides a useful matrix for targeted qPCR assay design. • PCR inhibition should be particularly emphasized for offshore environmental samples. • Contrary to eukaryotes, metabarcoding and qPCR for prokaryotes showed the same relationship to offshore contaminants. • Dinophyceae , Bacillariophyceae, and Alcanivorax abundances were correlated with only oil-related contaminants. • Beta-diversity of Foraminifera did not reflect the concentration of contaminants. [ABSTRACT FROM AUTHOR]