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Characterization, biosynthetic studies and subcellular localization of sterols from the marine sponge Teichaxinella morchella
Title
Characterization, biosynthetic studies and subcellular localization of sterols from the marine sponge Teichaxinella morchella.
Creator
Williams, Amanda Joy, Florida Atlantic University, Kerr, Russell G.
Abstract/Description
A-nor sterols have been isolated and characterized from the marine sponge Teichaxinella morchella using High Performance Liquid Chromatography, Nuclear Magnetic Resonance, and Mass Spectrometry. A cell free extract of T. morchella was used to determine the biosynthetic origin of the sterols. Incubation experiments with radiolabled Farnesyl Pyrophosphate and cholesterol showed that the sterols are coming from a dietary source. Subcellular localization studies showed that the sterols are part...
Show moreA-nor sterols have been isolated and characterized from the marine sponge Teichaxinella morchella using High Performance Liquid Chromatography, Nuclear Magnetic Resonance, and Mass Spectrometry. A cell free extract of T. morchella was used to determine the biosynthetic origin of the sterols. Incubation experiments with radiolabled Farnesyl Pyrophosphate and cholesterol showed that the sterols are coming from a dietary source. Subcellular localization studies showed that the sterols are part of the cell membrane.
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Date Issued
2001
PURL
http://purl.flvc.org/fcla/dt/12865
Subject Headings
Sponges, Sterols
Format
Document (PDF)
Chemotaxonomy of the marine sponge Xestospongia muta
Title
Chemotaxonomy of the marine sponge Xestospongia muta.
Creator
Reddy, Manoj Kumar., Florida Atlantic University, Kerr, Russell G.
Abstract/Description
Chemical analysis of large number of specimens of the sponge Xestospongia muta have revealed the existence of three distinct sterol chemotypes. Since sponges are well known to contain a diverse array of all classes of lipids, the utility of fatty acid composition as a chemotaxonomic tool for Xestospongia muta has been addressed. Further the biosynthetic capabilities of the three chemotypes are being evaluated for possible taxonomic use. Further the utility of TLC and NMR as additional...
Show moreChemical analysis of large number of specimens of the sponge Xestospongia muta have revealed the existence of three distinct sterol chemotypes. Since sponges are well known to contain a diverse array of all classes of lipids, the utility of fatty acid composition as a chemotaxonomic tool for Xestospongia muta has been addressed. Further the biosynthetic capabilities of the three chemotypes are being evaluated for possible taxonomic use. Further the utility of TLC and NMR as additional taxonomic tools has also been evaluated.
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Date Issued
1995
PURL
http://purl.flvc.org/fcla/dt/15167
Subject Headings
Chemotaxonomy, Sponges, Sterols
Format
Document (PDF)
Effects of stressors on differential gene expression and secondary metabolites by Axinella corrugata
Title
Effects of stressors on differential gene expression and secondary metabolites by Axinella corrugata.
Creator
Grima, Jennifer., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Sponges are an important source of bioactive marine natural products, or secondary metabolites. The common Caribbean reef sponge, Axinella corrugata, produces an antitumor and antibacterial chemical, stevensine. This study determined whether environmental stressors, such as elevated temperature and exposure to Amphibalanus amphitrite larvae, affect the production of stevensine by A.corrugata and if the stressors caused A.corrugata to exhibit differential gene expression. Temperature stress...
Show moreSponges are an important source of bioactive marine natural products, or secondary metabolites. The common Caribbean reef sponge, Axinella corrugata, produces an antitumor and antibacterial chemical, stevensine. This study determined whether environmental stressors, such as elevated temperature and exposure to Amphibalanus amphitrite larvae, affect the production of stevensine by A.corrugata and if the stressors caused A.corrugata to exhibit differential gene expression. Temperature stress resulted in no significant change in the production of stevensine; only two genes were significantly differentially expressed, including hsp70. Larval stressed resulted in increased production of stevensine and significant differential gene expression (more than seventy genes). This study suggests that A.corrugata may be resilient to elevations in temperature and that one of stevensine's roles in nature is as an antifoulant.
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Date Issued
2013
PURL
http://purl.flvc.org/fcla/dt/3360781
Subject Headings
Axinellida, Sponges, Marine pharmacology, Adaptation (Biology), Gene expression, Genetic regulation, Stress (Physiology), Ecophysiology
Format
Document (PDF)
ESTABLISHING A SPONGE HYBRIDOMA FOR THE IN VITRO PRODUCTION OF A MARINE NATURAL PRODUCT
Title
ESTABLISHING A SPONGE HYBRIDOMA FOR THE IN VITRO PRODUCTION OF A MARINE NATURAL PRODUCT.
Creator
Dougan, Cassady, Pomponi, Shirley A., Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
Abstract/Description
Marine sponges are one of the most prolific sources of chemical compounds with pharmaceutical importance. To establish a supply of such compounds large enough for clinical development, in vitro production methodology was investigated. Since all sponge cells do not divide in culture, it was hypothesized that the fusion of rapidly dividing cells of a sponge that does not produce any compounds of interest with cells of a nondividing but compound-producing sponge would result in a hybridoma that...
Show moreMarine sponges are one of the most prolific sources of chemical compounds with pharmaceutical importance. To establish a supply of such compounds large enough for clinical development, in vitro production methodology was investigated. Since all sponge cells do not divide in culture, it was hypothesized that the fusion of rapidly dividing cells of a sponge that does not produce any compounds of interest with cells of a nondividing but compound-producing sponge would result in a hybridoma that produces the compound of interest. In this study, hybridomas have been produced with cells of two marine sponges, Axinella corrugata, which produces the antitumor compound stevensine, and Geodia neptuni, which divides rapidly in a nutrient medium optimized for sponge cell culture. Successful hybridization and subsequent cell division and in vitro stevensine production may unlock the potential for sustainable mass production of other sponge-derived compounds.
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Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00014024
Subject Headings
Marine natural products, Sponges, Hybridomas, In vitro
Format
Document (PDF)
EVALUATION OF 3-D CULTURE METHODS FOR MARINE SPONGES
Title
EVALUATION OF 3-D CULTURE METHODS FOR MARINE SPONGES.
Creator
Urban-Gedamke, Elizabeth, Pomponi, Shirley A., Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
Abstract/Description
Marine sponges are economically and environmentally valuable, but restoration, commercial, and biomedical demands exceed what wild populations and aquaculture can provide. In vitro culture of sponge cells is a promising alternative, but has remained elusive until recent breakthroughs involving improved nutrient medium M1 in two-dimensional culture. The advantages of three-dimensional over two-dimensional cell culture have been increasingly recognized. Here we report the successful 21-day...
Show moreMarine sponges are economically and environmentally valuable, but restoration, commercial, and biomedical demands exceed what wild populations and aquaculture can provide. In vitro culture of sponge cells is a promising alternative, but has remained elusive until recent breakthroughs involving improved nutrient medium M1 in two-dimensional culture. The advantages of three-dimensional over two-dimensional cell culture have been increasingly recognized. Here we report the successful 21-day culture of cells from the marine sponge Geodia neptuni using multiple three-dimensional cell culture methods: FibraCel© disks, thin hydrogel layers, gel micro droplets, and spheroid cell culture. These methods performed comparably to two-dimensional control cultures, and each method offers advantages for restoration or in vitro applications using sponge cells. Further optimization of these methods may lead to the ability to culture fully functioning sponges from dissociated, cryopreserved cells, which will reduce the need for wild harvest of sponge tissues for commercial, restoration, and biomedical purposes.
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Date Issued
2021
PURL
http://purl.flvc.org/fau/fd/FA00013726
Subject Headings
Sponges, Cell Culture--methods
Format
Document (PDF)
extraction optimization and determination of the absolute configuartion of clathric acid
Title
An extraction optimization and determination of the absolute configuartion of clathric acid.
Creator
Rueda de Leon, Rolando, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
Current research in natural products has heavily focused on the identification of potent biologically active compounds, specifically for drug development. The project detailed in this thesis focuses on the extraction of compounds from marine invertebrates as well as defining the absolute configuration for a compound. Utilizing marine invertebrates, the sonications method developed in this thesis provides an alternative approach to rapidly extract compounds for primary screening. This method...
Show moreCurrent research in natural products has heavily focused on the identification of potent biologically active compounds, specifically for drug development. The project detailed in this thesis focuses on the extraction of compounds from marine invertebrates as well as defining the absolute configuration for a compound. Utilizing marine invertebrates, the sonications method developed in this thesis provides an alternative approach to rapidly extract compounds for primary screening. This method is viable compared to a traditional overnight extraction method, without suffering compound degredation... Previously, clathric acid was isolated from an unknown Clathria sp. This compound is a bibyblic C-21 terpenoid shown to have mild antimicrobial activity against gram positive bacteria. With only its relative configuration established, additional amounts of clathric acid were required to define the overall absolute configuration. Identifying the Clathria sp. to be Clathria compressa, through spicule analysis, additional sponge tissues were then collected off the coast of Boca Raton, Florida to isolate additional quatities of clathric acid. The absolulte configuration was determined through circular dichroism and the octant rule to establish a final configuration for clathric acid's four carbon stereocenters to be: (3S, 7S, 8R, and 12S).
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Date Issued
2012
PURL
http://purl.flvc.org/FAU/3355874
Subject Headings
Organic compounds, Analysis, Extraction (Chemistry), Natural products, Therapeutic use, Marine biotechology, Marine resources, Research, Sponges, Ecology
Format
Document (PDF)
In vitro biosynthetic studies of stevensine, a natural product from the sponge Teichaxinella morchella
Title
In vitro biosynthetic studies of stevensine, a natural product from the sponge Teichaxinella morchella.
Creator
Andrade, Paul., Florida Atlantic University, Kerr, Russell G.
Abstract/Description
Stevensine is a biologically active secondary metabolite produced by several marine sponges, including Teichaxinella morchella. Two in vitro methods were used to investigate the biosynthetic origin of stevensine in the sponge T. morchella. A cell-free enzyme extract was developed to test for the incorporation of the potential radiolabeled metabolic precursors histidine, arginine, ornithine, and proline. Secondly, cell cultures of T. morchella were used to determine the biosynthetic origin of...
Show moreStevensine is a biologically active secondary metabolite produced by several marine sponges, including Teichaxinella morchella. Two in vitro methods were used to investigate the biosynthetic origin of stevensine in the sponge T. morchella. A cell-free enzyme extract was developed to test for the incorporation of the potential radiolabeled metabolic precursors histidine, arginine, ornithine, and proline. Secondly, cell cultures of T. morchella were used to determine the biosynthetic origin of stevensine from the radiolabeled amino acids histidine, arginine, ornithine, and proline. Histidine and ornithine/proline were converted to stevensine in the cell culture system. This represents the first study involving the use of cell cultures of a marine invertebrate to investigate the biosynthesis of a biologically active natural product. An understanding of the biosynthetic process leading to the production of this compound in the source organism could lead to the development of more efficient and environmentally safer production methods.
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Date Issued
1999
PURL
http://purl.flvc.org/fcla/dt/15620
Subject Headings
Sponges, Marine biotechnology, Marine pharmacology
Format
Document (PDF)
Isolation and structure elucidation of novel compounds from marine cyanobacteria
Title
Isolation and structure elucidation of novel compounds from marine cyanobacteria.
Creator
Meickle, Theresa, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
The work of this dissertation examined the secondary metabolites of several blooms of the marine cyanobacterium Lyngbya collected in Guam and Florida with an emphasis on the isolation and structure elucidation of novel biologically active compounds. The introduction in Chapter One provides a brief history of marine natural products, a description of cyanobacteria and a summary of peptides isolated from Lyngbya collected in the Caribbean. In Chapter Two, a bioassay-guided fractionation of a...
Show moreThe work of this dissertation examined the secondary metabolites of several blooms of the marine cyanobacterium Lyngbya collected in Guam and Florida with an emphasis on the isolation and structure elucidation of novel biologically active compounds. The introduction in Chapter One provides a brief history of marine natural products, a description of cyanobacteria and a summary of peptides isolated from Lyngbya collected in the Caribbean. In Chapter Two, a bioassay-guided fractionation of a Floridian collection of Lyngbya polychroa led to the isolation and structural determination of the cytotoxin desacetylmicrocolin B and the known compounds microcolins A and B. The structures were established by nuclear magnetic resonance (NMR) spectroscopic analysis. All three compounds inhibited the growth of cancer cell lines HT-29 and IMR-32 at nanomolar concentrations. Microcolins A and B were found to have little activity in the ecological assay against the marine fungus Dendryphiella salina. Chapter Three describes the isolation and structure elucidation of the glycosidic, acyl proline derivative tumonoic acid J from a sample Lyngbya sp. collected in Guam. The planar structure was determined by 1D and 2D NMR spectroscopy in conjunction with high resolution-mass spectrometry (HR-MS) data. Tumonoic acid J showed moderate activity in the ecological assay against the marine fungus D. salina. In Chapter Four, NMR-guided fractionation of a Floridian sample of Lyngbya majuscula led to the isolation of two novel cyclic peptides porpoisamides A and B. The planar structures were determined by 1D and 2D NMR spectroscopy with HR-MS data. The absolute configurations of these two compounds were defined through chiral chromatographic methods and derivatization techniques., The porpoisamides showed only moderate activity in cytotoxicity assays against cancer cell lines HCT-116 and U2OS. Finally, Chapter Five examines a potential ecological role of compounds isolated from marine cyanobacte ria. These secondary metabolites may function as chemical defenses against competing microorganisms within marine environments. Compounds isolated from cyanobacteria were tested for anti-fungal activity against the saprophytic marine fungus D. salina. Three of the six compounds tested produced inhibitory activity at or below their natural concentration.
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Date Issued
2010
PURL
http://purl.flvc.org/FAU/2978991
Subject Headings
Sponges, Ecology, Cyanobacteria, Biological control, Aquatic ecology
Format
Document (PDF)
Therapeutic potential, mechanism of action, and ecology of novel marine natural products
Title
Therapeutic potential, mechanism of action, and ecology of novel marine natural products.
Creator
Winder, Priscilla L., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
The projects described in this dissertation are focused on compounds derived from the marine environment. Chapter 1 gives an introduction to the study of marine natural products to treat human ailments and a thorough review on compounds from lithistid sponges that have been isolated or synthesized since 2000. Chapter 2 describes the isolation and structure elucidation of two sesquiterpene substituted benzoquinone derivatives, petrosiquinones A and B, from a deep-water marine sponge from the...
Show moreThe projects described in this dissertation are focused on compounds derived from the marine environment. Chapter 1 gives an introduction to the study of marine natural products to treat human ailments and a thorough review on compounds from lithistid sponges that have been isolated or synthesized since 2000. Chapter 2 describes the isolation and structure elucidation of two sesquiterpene substituted benzoquinone derivatives, petrosiquinones A and B, from a deep-water marine sponge from the Family Petrosiidae. Although initially purified following activity in a (Sb(B-catenin/Tcf4 assay they were later followed using tumor cell line cytotoxicity assays. Petrosiquinone A was the more active of the two compounds with moderate cytotoxicity in the DLD-1, PANC-1, and AsPC-1 cell lines. In Chapter 3, the isolation and structure elucidation of two new marine-derived macrolides, madeirolide A and B, isolated from a deep-water lithistid sponge of the genus Leiodermatium is described., They were isolated using numerous chromatographic techniques and the structures were elucidated on the basis of 1D and 2D NMR spectra coupled with high resolution-mass spectrometry (HR-MS) data. Madeirolide A and B inhibited the growth of the fungal pathogen Candida albicans with minimum inhibitory concentrations (MIC) of 12.5 and 25 (So(Bg/mL, respectively, but were not cytotoxic in tumor cell assays under the conditions tested. Chapter 4 describes work performed to determine the molecular target of lasonolide A using affinity chromatography. The target of lasonolide A is of interest since lasonolide A is known to kill cancer cells in vitro through a unique mechanism., This chapter highlights the research performed to create an affinity matrix with immobilized lasonolide. A target has not been confirmed but there are a number of interesting hits that are being pursued. In Chapter 5, a liquid chromatography-mass spectrometry (LC-MS) screening method was established in order to rapidly identify the metabolites from numerous collections of Lyngbya spp. obtained from Broward and Lee County, Florida sites that may help marine ecologists assess the effects of Lyngbya spp. blooms on the environment. A link between the metabolites produced and nutrients from both the algal tissue and water column was also explored.
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Date Issued
2009
PURL
http://purl.flvc.org/FAU/369392
Subject Headings
Natural products, Therapeutic use, Sponges, Ecology, Marine resources, Research, Marine biotechnology
Format
Document (PDF)