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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)
Origin and mechanism of terpene biosynthesis in Pseudopterogorgia spp
Title
Origin and mechanism of terpene biosynthesis in Pseudopterogorgia spp.
Creator
Boehnlein, Jennifer M., Florida Atlantic University, Kerr, Russell G.
Abstract/Description
The goal of this work was to investigate the biosynthetic origins of diterpene natural products (pseudopterosins, kallolides, bipinnatins, and cembrenes) from corals of the genus Pseudopterogorgia as well as the biosynthetic pathways by which they are produced. These studies have shown that the pseudopterosins from Pseudopterogorgia elisabethae are biosynthesized within the algal symbiont (or possibly a bacterium or fungus associated with the symbiont), are not inducible by manipulation of...
Show moreThe goal of this work was to investigate the biosynthetic origins of diterpene natural products (pseudopterosins, kallolides, bipinnatins, and cembrenes) from corals of the genus Pseudopterogorgia as well as the biosynthetic pathways by which they are produced. These studies have shown that the pseudopterosins from Pseudopterogorgia elisabethae are biosynthesized within the algal symbiont (or possibly a bacterium or fungus associated with the symbiont), are not inducible by manipulation of light levels, and do not change as a result of transplantation to new locations. Studies on Pseudopterogorgia bipinnata revealed that only one chemotype is capable of biosynthesizing the kallolide family of diterpenes. The biosynthetic pathway which gives rise to the kallolides has been shown to involve members of another family of diterpenes, the bipinnatins, which coexist within the coral holobiont. Two diterpene cyclase products have been discovered within P. bipinnata chemotype A, cembrene and neocembrene, and it has been shown that neocembrene gives rise to the kallolides. Finally, the enzymatic conversion of bipinnatin J to kallolide A has shown for the first time that these compounds are in fact biogenetically related.
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Date Issued
2006
PURL
http://purl.flvc.org/fcla/dt/12205
Subject Headings
Terpenes--Synthesis, Marine pharmacology, Alcyonacea, Biosynthesis, Anti-inflammatory agents
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)

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