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Isolation, Analysis and Origin of Bioactive Diterpenes in Pseudopterogorgia acerosa.
Title
Isolation, Analysis and Origin of Bioactive Diterpenes in Pseudopterogorgia acerosa.
Creator
Kate, Abhijeet S., Florida Atlantic University, Kerr, Russell G., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
Nature has served human kind m many ways, one of which is a source of medicines. Natural products from marine sources represent a relatively new area of research and have shown tremendous potential as a source of new chemical entities in drug discovery. Caribbean gorgomans corals of the genus Pseudopterogorgia have been shown to produce a variety of chemically interesting and biologically significant secondary metabolites. ln this dissertation, the Caribbean coral Pseudopterogorgia acerosa...
Show moreNature has served human kind m many ways, one of which is a source of medicines. Natural products from marine sources represent a relatively new area of research and have shown tremendous potential as a source of new chemical entities in drug discovery. Caribbean gorgomans corals of the genus Pseudopterogorgia have been shown to produce a variety of chemically interesting and biologically significant secondary metabolites. ln this dissertation, the Caribbean coral Pseudopterogorgia acerosa has been investigated for the presence of novel diterpenes and these compounds were found to belong to three different classes: pseudopteranoids, bis-pseudopteranoids and lipidyl pseudopteranes. Nine of these were new compounds. The structural elucidation of these compounds was performed using spectroscopic means such as l D and 20 NMR, and mass spectroscopy. There is growing evidence that secondary metabolites isolated from manne invertebrates may actually be produced by a bacterial symbiont. The research studies in our laboratory regarding the source of diterpenes in the selected gorgonian corals suggested a bacterial origin. The hypothesis that coral associated bacteria are the source of diterpenes in the coral P. acerosa, was evaluated using the series of experiments and evidence supported this biosynthetic origin. A study comparing the "gall" tissue and healthy coral tissue in terms of diterpene content and culturable bacterial communities showed that different groups of diterpenes were concentrated in different coral tissue types. It was also observed that the bacterial populations associated with the "gall" and healthy tissues were considerably different. Furthermore, observed specificity in antimicrobial activity of certain groups of compounds against bacteria isolated from the same coral suggested the ecological role of these compounds. This work with "gall" tissue supports the hypothesis that diseased coral tissue represents an excellent source of bioactive natural products for drug discovery. Additionaly, a simple LC-MS method was developed for the analysis of anticancer drug carmustine in plasma.
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Date Issued
2008
PURL
http://purl.flvc.org/fau/fd/FA00000864
Subject Headings
Marine pharmacology, Coral reef ecology--Caribbean Area, Natural products--Synthesis
Format
Document (PDF)
Isolation of the fatty acid synthetase from the marine invertebrate Bugula neritina
Title
Isolation of the fatty acid synthetase from the marine invertebrate Bugula neritina.
Creator
Koh, Francis H., Florida Atlantic University, Kerr, Russell G., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
The fatty acid synthetase (FAS) from the marine invertebrate Bugula neritina was isolated using cold ethanol precipitation followed by the sequence of G-100 and G-200 size exclusion columns. Native gel analysis indicates the isolation of the FAS and the elution volume from the G-100 column suggests the FAS to be ~282kd. One band with a molecular weight of 66 kDa appeared on the SDS gel of the G-200 sample (F17-30) that eluted at 52.5 mL. The G-200 sample that eluted at 19.2 mL (F1-6)...
Show moreThe fatty acid synthetase (FAS) from the marine invertebrate Bugula neritina was isolated using cold ethanol precipitation followed by the sequence of G-100 and G-200 size exclusion columns. Native gel analysis indicates the isolation of the FAS and the elution volume from the G-100 column suggests the FAS to be ~282kd. One band with a molecular weight of 66 kDa appeared on the SDS gel of the G-200 sample (F17-30) that eluted at 52.5 mL. The G-200 sample that eluted at 19.2 mL (F1-6) displayed two predominant bands on the SDS gel corresponding to molecular weights 66 kDa and 97 kDa. Both F1-6 and F17-30 showed FAS activity displaying de novo production of myristic and palmitic acids. From the sequence of purification starting from the cell-free extract (CFE) to the F17-30 sample, a 240 fold increase in specific activity was observed. The Type II FAS experiments showed no substantial evidence of activity, namely of the beta-Hydroxybutyryl acyl-dehydrase and the enoyl reductase enzymes.
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Date Issued
1998
PURL
http://purl.flvc.org/fcla/dt/15546
Subject Headings
Fatty acids--Synthesis, Marine pharmacology, Bryozoa
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)
Biosynthetic Studies of the Bryostatins, Anticancer Agents from the Marine Bryozoan Bugu/a neritina
Title
Biosynthetic Studies of the Bryostatins, Anticancer Agents from the Marine Bryozoan Bugu/a neritina.
Creator
Lawry, Joseph, Kerr, Russell G., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
The bryostatins are a family of macrolide lactones isolated from the marine bryozoan Bugu/a neritina. Since its detection in 1968, bryostatin 1 has demonstrated remarkable anticancer, immunopotentiating, biomodulatory and radioprotective effects which result mainly from its ability to activate protein kinase C, a family of isozymes involved in cellular signal transduction. It is currently being tested in several phase I and phase II clinical trials as a potential anticancer drug for leukemia,...
Show moreThe bryostatins are a family of macrolide lactones isolated from the marine bryozoan Bugu/a neritina. Since its detection in 1968, bryostatin 1 has demonstrated remarkable anticancer, immunopotentiating, biomodulatory and radioprotective effects which result mainly from its ability to activate protein kinase C, a family of isozymes involved in cellular signal transduction. It is currently being tested in several phase I and phase II clinical trials as a potential anticancer drug for leukemia, melanoma and nephrotoma. A series of experiments was undertaken to elucidate the biosynthetic origins of bryostatin, using a fortified crude cell-free enzyme preparation and radiolabelled precursors. A regional characterization of Bugula neritina from Sicily, Italy and Daytona Beach, Florida is also described.
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Date Issued
1997
PURL
http://purl.flvc.org/fau/fd/FA00000787
Subject Headings
Macrolide antibiotics, Bryozoa, Marine pharmacology
Format
Document (PDF)