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Exploration of Methods to Identify Biosynthetic Genes and the Origin of Biosynthesis in Marine Octocorals
Title
Exploration of Methods to Identify Biosynthetic Genes and the Origin of Biosynthesis in Marine Octocorals.
Creator
Ranzer, Llanie Karen, Florida Atlantic University, Kerr, Russell G., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
The overall goal of this research was to isolate key genes involved in the diterpene biosynthesis from Euniceafusca and Erythropodium caribaeorum using molecular biology techniques. The initial goal was to use fuscol induced cell cultures of Symbiodinium sp. isolated from E. fusca and to develop an approach based on differential display of mRNA-reverse transcription-PeR. Together with inverse PCR, these techniques ultimately provided a full-length farnesyl diphosphate synthase sequence....
Show moreThe overall goal of this research was to isolate key genes involved in the diterpene biosynthesis from Euniceafusca and Erythropodium caribaeorum using molecular biology techniques. The initial goal was to use fuscol induced cell cultures of Symbiodinium sp. isolated from E. fusca and to develop an approach based on differential display of mRNA-reverse transcription-PeR. Together with inverse PCR, these techniques ultimately provided a full-length farnesyl diphosphate synthase sequence. Functional expression of this enzyme was demonstrated with the addition of appropriate substrates and confirmed by chromatography. From this data, degenerate primer based PCR was used to isolate putative geranylgeranyl diphosphate biosynthetic genes from E. caribaeorum. Both chemical and genetic examinations of Pseudopterogorgia elisabethae eggs and their associated Symbiodinium sp. were employed to identify the biosynthetic origin of their diterpenes. Terpene content and biosynthetic capabilities of azooxanthellae eggs demonstrated the presence of pseudopterosins but also indicated that the eggs were not capable of producing these compounds. Likewise, no correlation could be observed for the phylogenetic relationships inferred for the Symbiodinium sp., with that of the terpene chemistry present in P. elisabethae. This finding leads us to speculate about an additional source of terpene production within this coral. Based on these and other recent findings suggesting symbiotic bacteria as the source of secondary metabolites from marine invertebrates, bacterial assemblages from E. caribaeorum were examined. This study revealed considerable phylogenetic bacterial diversity within this coral and the identification of several bacteria known to produce terpenes in other organisms.
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Date Issued
2006
PURL
http://purl.flvc.org/fau/fd/FA00000874
Subject Headings
Coral reef ecology, Diterpenes, Biosynthesis, Terpenes--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)
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, Characterization and Synthesis of New Diterpenes from Pseudopterogorgia elisabethae
Title
Isolation, Characterization and Synthesis of New Diterpenes from Pseudopterogorgia elisabethae.
Creator
Wan, Zhongliang, Florida Atlantic University, Kerr, Russell G., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
Pseudopterogorgia elisabethae is a known source of structurally interesting bioactive metabolites. A detailed search for new, related compounds was undertaken in this study which resulted in the isolation and characterization of more than ten new diterpenes with serrulatane and ileabethane skeletons. Some of the new compounds isolated are closely related terpenes with significant biological activity and others are likely to be key biosynthetic intermediates. As a component of the development...
Show morePseudopterogorgia elisabethae is a known source of structurally interesting bioactive metabolites. A detailed search for new, related compounds was undertaken in this study which resulted in the isolation and characterization of more than ten new diterpenes with serrulatane and ileabethane skeletons. Some of the new compounds isolated are closely related terpenes with significant biological activity and others are likely to be key biosynthetic intermediates. As a component of the development of a production method of anti-inflammatory compounds such as seco-pseudopterosin and elisabethadione, a synthesis of a seco-pseudoperosin aglycone from elisabethatriene was developed.
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Date Issued
2006
PURL
http://purl.flvc.org/fau/fd/FA00000883
Subject Headings
Biosynthesis, Diterpenes--Synthesis, Marine invertebrates, Anti-inflammatory agents
Format
Document (PDF)

Pages