Valerie Paul - Academia.edu (original) (raw)

Papers by Valerie Paul

Marine Drugs, Oct 24, 2023

ACS Chemical Biology, Mar 3, 2016

Journal of Natural Products, 2007

Bioorganic & Medicinal Chemistry, Jun 1, 2002

Two collections of the marine cyanobacterium Lyngbya sp. from Guam and Palau that both afforded t... more Two collections of the marine cyanobacterium Lyngbya sp. from Guam and Palau that both afforded the potent cytotoxin apratoxin A (1) each yielded different structural analogues with lower degrees of methylation. The new apratoxins, termed apratoxins B (2) and C (3), were evaluated for their in vitro cytotoxicity along with semisynthetic E-dehydroapratoxin A (4) to identify key structural elements responsible for the cytotoxicity and to initiate SAR studies on this novel family of depsipeptides. All analogues 2-4 displayed weaker cytotoxicity than 1, but to different extents. While compound 3 closely approached the cytotoxicity of 1, compounds 2 and 4 exhibited significantly reduced activity, possibly also related to a conformational change. The 16S rRNA genes of the different apratoxin producers have partially been sequenced and compared, and other genetic differences are currently being revealed.

Marine Ecology Progress Series, Sep 10, 2020

Biotic interactions have critical effects on the structure of ecological communities, and the var... more Biotic interactions have critical effects on the structure of ecological communities, and the variation in the strength of these interactions over space and time contributes to biogeographic variation in communities. Predation shapes community composition in a variety of habitats, although there have been comparatively few experimental studies of these effects across latitudinal scales. We tested the impact of predator exclusion on the development of epifaunal communities across 3 sites (Florida [USA], Belize, and Panama) in seagrass habitats dominated by Thalassia testudinum using caged and uncaged settlement panels. We found that predators altered composition and slowed development of epifaunal communities. The nature and magnitude of these effects, however, were complex, site-dependent, and tightly coupled to community development. Fast-growing, soft-bodied species dominated space when predators were excluded, while more resistant calcifying species were dominant in communities exposed to predators. In Panama, non-native ascidians dominated communities in cages, while ascidians were consumed when exposed to predators, indicating the importance of biotic resistance at that site. Predators also reduced the abundance of associated small mobile fauna, and the positive correlation between mobile faunal abundances and sessile biomass in our study suggests a potential indirect effect of predator-mediated habitat modification. Overall, prey characteristics were important in explaining the site-specific effects of predators on communities, indicating that taxonomic resolution can influence the results of multi-regional studies examining the mechanisms affecting community structure.

Tetrahedron, 1990

... Rolf Herb, Anthony R. Carroll, Wesley Y. Yoshida and Paul J. Scheuer, *. Valerie J. Paul, *. ... more ... Rolf Herb, Anthony R. Carroll, Wesley Y. Yoshida and Paul J. Scheuer, *. Valerie J. Paul, *. ... All three herblndoles are cytotoxic against KB cells at NIC of 5 pg mL for A(l); 10 ug oL for B(2) and 10 Mg mL for C(3). 1 ROb 2 R'CHiCH) 3R. ...

Environmental Science & Technology, Jan 21, 2015

Journal of Natural Products, Nov 1, 2002

A Palauan collection of the marine cyanobacterium Lyngbya sp., which had already afforded diverse... more A Palauan collection of the marine cyanobacterium Lyngbya sp., which had already afforded diverse peptide-based cytotoxins, also yielded a new glycoside macrolide exhibiting slight cytotoxicity. The compound was termed lyngbyaloside B (1) due to its structural analogy to the previously isolated lyngbyaloside (2). Lyngbyaloside B (1) appears to be only the third glycoside macrolide and second brominated compound of its kind from a marine cyanobacterium. Its gross structure was determined by a combination of NMR spectroscopy and mass spectrometric techniques. The relative stereochemistry for the 12 stereocenters is proposed on the basis of proton-proton spin-coupling constants and ROESY data.

Frontiers in Marine Science, Oct 27, 2021

BMC Genomics, Nov 13, 2019

Journal of Natural Products, Oct 1, 2007

Three new analogues of dolastatin 13, termed lyngbyastatins 5-7 ( 1- 3), were isolated from two d... more Three new analogues of dolastatin 13, termed lyngbyastatins 5-7 ( 1- 3), were isolated from two different collections of marine cyanobacteria, Lyngbya spp., from South Florida. Their planar structures were deduced by a combination of NMR techniques, and the absolute configurations were established by modified Marfey's analysis of the acid hydrolyzates. The related cyclodepsipeptide somamide B ( 4), previously reported from a Fijian cyanobacterium, has also been found in one of the extracts, and its absolute stereochemistry was unambiguously assigned for the first time. Compounds 1- 4 were found to selectively inhibit elastase over several other serine proteases, with IC50 values for porcine pancreatic elastase ranging from 3 to 10 nM.

Journal of Organic Chemistry, Jul 1, 1988

... Other grant support was from Syntex Inc. We thank Mr. Jim Loo (UCSC) for assistance with NMR ... more ... Other grant support was from Syntex Inc. We thank Mr. Jim Loo (UCSC) for assistance with NMR measurements, Dr. Julie Leary (UCB MS lab) for the FABMS data, and Dr. Tom Matthews (Syntex) for bioactivity data. Registry No. ...

Journal of the American Chemical Society, May 15, 2001

Anthropogenic activities increase sediment suspended in the water column and deposition on reefs ... more Anthropogenic activities increase sediment suspended in the water column and deposition on reefs can be largely dependent on colony morphology. Massive and plating corals have a high capacity to trap sediments, and active removal mechanisms can be energetically costly. Branching corals trap less sediment, but are more susceptible to light limitation caused by suspended sediment. Despite deleterious effects of sediments on corals, few studies have examined the molecular response of corals with different morphological characteristics to sediment stress. To address this knowledge gap, this study assessed the transcriptomic responses of branching and massive corals in Florida and Hawai□i to varying levels of sediment exposure. Gene expression analysis revealed a molecular responsiveness to sediments across species and sites. Differentially Gene Expression (DEG) followed by Gene Ontology (GO) enrichment analysis identified that branching corals had the largest transcriptomic response to ...

Light data collected from loggers deployed at the Thalassia Experimental Network (TEN) sites in t... more Light data collected from loggers deployed at the Thalassia Experimental Network (TEN) sites in the Western Atlantic from 2018-2019.

Additional file 17: Figure S15. BLASTp report for ORF7, ORF8, and ORF9.

Marine Drugs, Oct 24, 2023

ACS Chemical Biology, Mar 3, 2016

Journal of Natural Products, 2007

Bioorganic & Medicinal Chemistry, Jun 1, 2002

Two collections of the marine cyanobacterium Lyngbya sp. from Guam and Palau that both afforded t... more Two collections of the marine cyanobacterium Lyngbya sp. from Guam and Palau that both afforded the potent cytotoxin apratoxin A (1) each yielded different structural analogues with lower degrees of methylation. The new apratoxins, termed apratoxins B (2) and C (3), were evaluated for their in vitro cytotoxicity along with semisynthetic E-dehydroapratoxin A (4) to identify key structural elements responsible for the cytotoxicity and to initiate SAR studies on this novel family of depsipeptides. All analogues 2-4 displayed weaker cytotoxicity than 1, but to different extents. While compound 3 closely approached the cytotoxicity of 1, compounds 2 and 4 exhibited significantly reduced activity, possibly also related to a conformational change. The 16S rRNA genes of the different apratoxin producers have partially been sequenced and compared, and other genetic differences are currently being revealed.

Marine Ecology Progress Series, Sep 10, 2020

Biotic interactions have critical effects on the structure of ecological communities, and the var... more Biotic interactions have critical effects on the structure of ecological communities, and the variation in the strength of these interactions over space and time contributes to biogeographic variation in communities. Predation shapes community composition in a variety of habitats, although there have been comparatively few experimental studies of these effects across latitudinal scales. We tested the impact of predator exclusion on the development of epifaunal communities across 3 sites (Florida [USA], Belize, and Panama) in seagrass habitats dominated by Thalassia testudinum using caged and uncaged settlement panels. We found that predators altered composition and slowed development of epifaunal communities. The nature and magnitude of these effects, however, were complex, site-dependent, and tightly coupled to community development. Fast-growing, soft-bodied species dominated space when predators were excluded, while more resistant calcifying species were dominant in communities exposed to predators. In Panama, non-native ascidians dominated communities in cages, while ascidians were consumed when exposed to predators, indicating the importance of biotic resistance at that site. Predators also reduced the abundance of associated small mobile fauna, and the positive correlation between mobile faunal abundances and sessile biomass in our study suggests a potential indirect effect of predator-mediated habitat modification. Overall, prey characteristics were important in explaining the site-specific effects of predators on communities, indicating that taxonomic resolution can influence the results of multi-regional studies examining the mechanisms affecting community structure.

Tetrahedron, 1990

... Rolf Herb, Anthony R. Carroll, Wesley Y. Yoshida and Paul J. Scheuer, *. Valerie J. Paul, *. ... more ... Rolf Herb, Anthony R. Carroll, Wesley Y. Yoshida and Paul J. Scheuer, *. Valerie J. Paul, *. ... All three herblndoles are cytotoxic against KB cells at NIC of 5 pg mL for A(l); 10 ug oL for B(2) and 10 Mg mL for C(3). 1 ROb 2 R'CHiCH) 3R. ...

Environmental Science & Technology, Jan 21, 2015

Journal of Natural Products, Nov 1, 2002

A Palauan collection of the marine cyanobacterium Lyngbya sp., which had already afforded diverse... more A Palauan collection of the marine cyanobacterium Lyngbya sp., which had already afforded diverse peptide-based cytotoxins, also yielded a new glycoside macrolide exhibiting slight cytotoxicity. The compound was termed lyngbyaloside B (1) due to its structural analogy to the previously isolated lyngbyaloside (2). Lyngbyaloside B (1) appears to be only the third glycoside macrolide and second brominated compound of its kind from a marine cyanobacterium. Its gross structure was determined by a combination of NMR spectroscopy and mass spectrometric techniques. The relative stereochemistry for the 12 stereocenters is proposed on the basis of proton-proton spin-coupling constants and ROESY data.

Frontiers in Marine Science, Oct 27, 2021

BMC Genomics, Nov 13, 2019

Journal of Natural Products, Oct 1, 2007

Three new analogues of dolastatin 13, termed lyngbyastatins 5-7 ( 1- 3), were isolated from two d... more Three new analogues of dolastatin 13, termed lyngbyastatins 5-7 ( 1- 3), were isolated from two different collections of marine cyanobacteria, Lyngbya spp., from South Florida. Their planar structures were deduced by a combination of NMR techniques, and the absolute configurations were established by modified Marfey's analysis of the acid hydrolyzates. The related cyclodepsipeptide somamide B ( 4), previously reported from a Fijian cyanobacterium, has also been found in one of the extracts, and its absolute stereochemistry was unambiguously assigned for the first time. Compounds 1- 4 were found to selectively inhibit elastase over several other serine proteases, with IC50 values for porcine pancreatic elastase ranging from 3 to 10 nM.

Journal of Organic Chemistry, Jul 1, 1988

... Other grant support was from Syntex Inc. We thank Mr. Jim Loo (UCSC) for assistance with NMR ... more ... Other grant support was from Syntex Inc. We thank Mr. Jim Loo (UCSC) for assistance with NMR measurements, Dr. Julie Leary (UCB MS lab) for the FABMS data, and Dr. Tom Matthews (Syntex) for bioactivity data. Registry No. ...

Journal of the American Chemical Society, May 15, 2001

Anthropogenic activities increase sediment suspended in the water column and deposition on reefs ... more Anthropogenic activities increase sediment suspended in the water column and deposition on reefs can be largely dependent on colony morphology. Massive and plating corals have a high capacity to trap sediments, and active removal mechanisms can be energetically costly. Branching corals trap less sediment, but are more susceptible to light limitation caused by suspended sediment. Despite deleterious effects of sediments on corals, few studies have examined the molecular response of corals with different morphological characteristics to sediment stress. To address this knowledge gap, this study assessed the transcriptomic responses of branching and massive corals in Florida and Hawai□i to varying levels of sediment exposure. Gene expression analysis revealed a molecular responsiveness to sediments across species and sites. Differentially Gene Expression (DEG) followed by Gene Ontology (GO) enrichment analysis identified that branching corals had the largest transcriptomic response to ...

Light data collected from loggers deployed at the Thalassia Experimental Network (TEN) sites in t... more Light data collected from loggers deployed at the Thalassia Experimental Network (TEN) sites in the Western Atlantic from 2018-2019.

Additional file 17: Figure S15. BLASTp report for ORF7, ORF8, and ORF9.