Current Search: Nuclear magnetic resonance spectroscopy (x)
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- Title
- Influence of nitrogen availability on agar-polysaccharides from Gracilaria verrucosa strain G-16: structural analysis by NMR spectroscopy.
- Creator
- Chiles, Thomas C., Bird, Kimon T., Koehn, F. E., Harbor Branch Oceanographic Institute
- Date Issued
- 1989
- PURL
- http://purl.flvc.org/FCLA/DT/3333140
- Subject Headings
- Gracilaria verrucosa, Agar, Polysaccharides, Nitrogen, Nuclear magnetic resonance spectroscopy
- Format
- Document (PDF)
- Title
- Dihydroxyaerothionin and aerophobin I. Two brominated tyrosine metabolites from the deep water marine sponge Verongula rigida.
- Creator
- Gunasekera, M., Harbor Branch Oceanographic Institute
- Date Issued
- 1989
- PURL
- http://purl.flvc.org/FCLA/DT/3332958
- Subject Headings
- Sponges, Tyrosine, Demospongiae, Marine metabolites, Nuclear magnetic resonance spectroscopy
- Format
- Document (PDF)
- Title
- Discorhabdins S, T, and U, New Cytotoxic Pyrroloiminoquinones from a Deep‐Water Caribbean Sponge of the Genus Batzella.
- Creator
- Gunasekera, Sarath P., Zuleta, Ignacio A., Longley, Ross E, Wright, Amy E., Pomponi, Shirley A.
- Date Issued
- 2003
- PURL
- http://purl.flvc.org/FCLA/DT/3164103
- Subject Headings
- Sponges, Nuclear magnetic resonance spectroscopy, Antineoplastic agents, Mass spectrometry, Pharmacognosy
- Format
- Document (PDF)
- Title
- PHOSPHORUS SEQUESTRATION AND BIOREMEDIATION: PHOSPHORUS-31 NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY.
- Creator
- Duersch, Bobby G., Louda, J. William, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
- Abstract/Description
-
Eutrophication is an increase in primary plant nutrients (Nitrogen [N] and Phosphorus [P]) in oceans, estuaries and lakes. The consequences of eutrophication are harmful algal blooms (HABs), resulting in algal toxin production and the depletion of oxygen as the extensive biomass decays. P is often the limiting nutrient and is viewed as a significant environmental problem. Most of the excess P that enters aquatic ecosystems originates from anthropogenic sources such as fertilizers, sewage,...
Show moreEutrophication is an increase in primary plant nutrients (Nitrogen [N] and Phosphorus [P]) in oceans, estuaries and lakes. The consequences of eutrophication are harmful algal blooms (HABs), resulting in algal toxin production and the depletion of oxygen as the extensive biomass decays. P is often the limiting nutrient and is viewed as a significant environmental problem. Most of the excess P that enters aquatic ecosystems originates from anthropogenic sources such as fertilizers, sewage, animal wastes, compost, crop residues, and wastewater. Over time, one of the main reservoirs of P becomes organic P (Po). We investigated the chemical nature and dynamics of P in cyanobacteria, horse manure, stormwater treatment areas, and rice fields. To better understand the chemical nature of P, the identification of specific P compounds was required, which was achieved through 31P nuclear magnetic resonance (NMR) spectroscopy. We investigated how paramagnetic metals and quadrupolar nuclei cause severe line broadening, peak shifts, and decreased the signal to noise ratio. Results revealed that certain Po forms are readily bioavailable to Microcystis aeruginosa. Additionally, the potential heterotrophic use of the organic portion (e.g., glucose, glycerol) of these P compounds are indicated for the growth and persistence of Microcystis aeruginosa. We showed that the cultivation of rice (Oryza sativa L.) had been found to effectively reduce P from agrarian soil and water through plant uptake and, therefore, minimizing downstream eutrophication. Soil, water, sugarcane, and rice plants at two different stages were analyzed for twelve different elements. Finally, we examined how a “relic” agrarian ditch in Stormwater Treatment Area 1 East (STA-1E) can be used for the retention and sequestration of P and other nutrients. The STAs were established to capture P from agricultural and other sources before reaching the Everglades. Retained P is primarily stored in the wetland soils and sediments, generated through a collection of interrelated physical, chemical, and biological processes.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013594
- Subject Headings
- Nuclear magnetic resonance spectroscopy, Eutrophication, Phosphorus--Environmental aspects, Bioremediation
- Format
- Document (PDF)
- Title
- Three-dimensional structure of the alpha-conotoxin EI determined by proton NMR spectroscopy.
- Creator
- Franco, Aldo, Florida Atlantic University, Mari, Frank
- Abstract/Description
-
The alpha-conotoxin EI is an 18-residue peptide (RDOCCYHPTCNMSNPQIC; 4-10, 5-18) isolated from the venom of Conus ermineus. This peptide targets the nicotinic acetylcholine receptor (nAChR) found in mammalian skeletal muscle and the electric organ of Torpedo. 2D-NMR methods and dynamical simulated annealing protocols have been used to determine the 3D structure of EI. 133 NOE-derived distances were used to produce 13 structures with minimum energy that complied with the NOE restraints. The...
Show moreThe alpha-conotoxin EI is an 18-residue peptide (RDOCCYHPTCNMSNPQIC; 4-10, 5-18) isolated from the venom of Conus ermineus. This peptide targets the nicotinic acetylcholine receptor (nAChR) found in mammalian skeletal muscle and the electric organ of Torpedo. 2D-NMR methods and dynamical simulated annealing protocols have been used to determine the 3D structure of EI. 133 NOE-derived distances were used to produce 13 structures with minimum energy that complied with the NOE restraints. The structure of EI is characterized by a helical loop between T9 and M12 that is stabilized by the C4-C10 disulfide bond and turns involving C4-C5 and N14-P15. The overall fold of EI is similar to that of other alpha4/7 conotoxins (PnIA/B, MII, EpI). However, unlike these other alpha4/7 conotoxins, EI targets the muscular type nAChR. The differences in selectivity can be attributed to the surface charge distribution among these alpha4/7 conotoxins.
Show less - Date Issued
- 1998
- PURL
- http://purl.flvc.org/fcla/dt/15609
- Subject Headings
- Conus--Venom, Peptides--Structure, Nuclear magnetic resonance spectroscopy
- Format
- Document (PDF)
- Title
- Revised stereochemistry for the structures of eudistomins C, K, E, F and L.
- Creator
- Blunt, J. W., Lake, R. J., Munro, M. H. G., Harbor Branch Oceanographic Institute
- Date Issued
- 1987
- PURL
- http://purl.flvc.org/FCLA/DT/3353801
- Subject Headings
- Carbolines, Stereochemistry, Ascidians, Nuclear magnetic resonance spectroscopy, Sea urchins--New Zealand
- Format
- Document (PDF)
- Title
- Plakolide A, a New γ‐Lactone from the Marine Sponge Plakortis sp.
- Creator
- Gunasekera, Sarath P., Isbrucker, Richard A., Longley, Ross E., Wright, Amy E., Pomponi, Shirley A., Reed, John K.
- Date Issued
- 2004
- PURL
- http://purl.flvc.org/FCLA/DT/3164104
- Subject Headings
- Sponges, Lactones, Acids, Nitric-oxide synthase, Nuclear magnetic resonance spectroscopy
- Format
- Document (PDF)