The Experts below are selected from a list of 8802 Experts worldwide ranked by ideXlab platform
Hal S. Alper - One of the best experts on this subject based on the ideXlab platform.
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Bioprospecting and evolving alternative xylose and arabinose pathway enzymes for use in Saccharomyces cerevisiae
Applied microbiology and biotechnology, 2015Co-Authors: Sun-mi Lee, Taylor Jellison, Hal S. AlperAbstract:Bioprospecting is an effective way to find novel enzymes from strains with desirable phenotypes. Such Bioprospecting has enabled organisms such as Saccharomyces cerevisiae to utilize nonnative pentose sugars. Yet, the efficiency of this pentose catabolism (especially for the case of arabinose) remains suboptimal. Thus, further pathway optimization or identification of novel, optimal pathways is needed. Previously, we identified a novel set of xylan catabolic pathway enzymes from a superior pentose-utilizing strain of Ustilago bevomyces. These enzymes were used to successfully engineer a xylan-utilizing S. cerevisiae through a blended approach of Bioprospecting and evolutionary engineering. Here, we expanded this approach to xylose and arabinose catabolic pathway engineering and demonstrated that bioprospected xylose and arabinose catabolic pathways from U. bevomyces offer alternative choices for enabling efficient pentose catabolism in S. cerevisiae. By introducing a novel set of xylose catabolic genes from U. bevomyces, growth rates were improved up to 85 % over a set of traditional Scheffersomyces stipitis pathway genes. In addition, we suggested an alternative arabinose catabolic pathway which, after directed evolution and pathway engineering, enabled S. cerevisiae to grow on arabinose as a sole carbon source in minimal medium with growth rates upwards of 0.05 h(-1). This pathway represents the most efficient growth of yeast on pure arabinose minimal medium. These pathways provide great starting points for further strain development and demonstrate the utility of Bioprospecting from U. bevomyces.
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xylan catabolism is improved by blending Bioprospecting and metabolic pathway engineering in saccharomyces cerevisiae
Biotechnology Journal, 2015Co-Authors: Sun-mi Lee, Taylor Jellison, Hal S. AlperAbstract:Complete utilization of all available carbon sources in lignocellulosic biomass still remains a challenge in engineering Saccharomyces cerevisiae. Even with efficient heterologous xylose catabolic pathways, S. cerevisiae is unable to utilize xylose in lignocellulosic biomass unless xylan is depolymerized to xylose. Here we demonstrate that a blended Bioprospecting approach along with pathway engineering and evolutionary engineering can be used to improve xylan catabolism in S. cerevisiae. Specifically, we perform whole genome sequencing-based Bioprospecting of a strain with remarkable pentose catabolic potential that we isolated and named Ustilago bevomyces. The heterologous expression of xylan catabolic genes enabled S. cerevisiae to grow on xylan as a single carbon source in minimal medium. A combination of Bioprospecting and metabolic pathway evolution demonstrated that the xylan catabolic pathway could be further improved. Ultimately, engineering efforts were able to achieve xylan conversion into ethanol of up to 0.22 g/L on minimal medium compositions with xylan. This pathway provides a novel starting point for improving lignocellulosic conversion by yeast.
Sun-mi Lee - One of the best experts on this subject based on the ideXlab platform.
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Bioprospecting and evolving alternative xylose and arabinose pathway enzymes for use in Saccharomyces cerevisiae
Applied microbiology and biotechnology, 2015Co-Authors: Sun-mi Lee, Taylor Jellison, Hal S. AlperAbstract:Bioprospecting is an effective way to find novel enzymes from strains with desirable phenotypes. Such Bioprospecting has enabled organisms such as Saccharomyces cerevisiae to utilize nonnative pentose sugars. Yet, the efficiency of this pentose catabolism (especially for the case of arabinose) remains suboptimal. Thus, further pathway optimization or identification of novel, optimal pathways is needed. Previously, we identified a novel set of xylan catabolic pathway enzymes from a superior pentose-utilizing strain of Ustilago bevomyces. These enzymes were used to successfully engineer a xylan-utilizing S. cerevisiae through a blended approach of Bioprospecting and evolutionary engineering. Here, we expanded this approach to xylose and arabinose catabolic pathway engineering and demonstrated that bioprospected xylose and arabinose catabolic pathways from U. bevomyces offer alternative choices for enabling efficient pentose catabolism in S. cerevisiae. By introducing a novel set of xylose catabolic genes from U. bevomyces, growth rates were improved up to 85 % over a set of traditional Scheffersomyces stipitis pathway genes. In addition, we suggested an alternative arabinose catabolic pathway which, after directed evolution and pathway engineering, enabled S. cerevisiae to grow on arabinose as a sole carbon source in minimal medium with growth rates upwards of 0.05 h(-1). This pathway represents the most efficient growth of yeast on pure arabinose minimal medium. These pathways provide great starting points for further strain development and demonstrate the utility of Bioprospecting from U. bevomyces.
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xylan catabolism is improved by blending Bioprospecting and metabolic pathway engineering in saccharomyces cerevisiae
Biotechnology Journal, 2015Co-Authors: Sun-mi Lee, Taylor Jellison, Hal S. AlperAbstract:Complete utilization of all available carbon sources in lignocellulosic biomass still remains a challenge in engineering Saccharomyces cerevisiae. Even with efficient heterologous xylose catabolic pathways, S. cerevisiae is unable to utilize xylose in lignocellulosic biomass unless xylan is depolymerized to xylose. Here we demonstrate that a blended Bioprospecting approach along with pathway engineering and evolutionary engineering can be used to improve xylan catabolism in S. cerevisiae. Specifically, we perform whole genome sequencing-based Bioprospecting of a strain with remarkable pentose catabolic potential that we isolated and named Ustilago bevomyces. The heterologous expression of xylan catabolic genes enabled S. cerevisiae to grow on xylan as a single carbon source in minimal medium. A combination of Bioprospecting and metabolic pathway evolution demonstrated that the xylan catabolic pathway could be further improved. Ultimately, engineering efforts were able to achieve xylan conversion into ethanol of up to 0.22 g/L on minimal medium compositions with xylan. This pathway provides a novel starting point for improving lignocellulosic conversion by yeast.
Travis J. Lybbert - One of the best experts on this subject based on the ideXlab platform.
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Who Benefits from a Bioprospecting-Based Boom? The Case of Argan Oil in Morocco
SSRN Electronic Journal, 2001Co-Authors: Travis J. Lybbert, Christopher B. Barrett, Hamid NarjisseAbstract:This paper breaks new ground in the literature on Bioprospecting by evaluating the local welfare effects associated with the successful Bioprospecting-driven commercialization of argan oil in southwestern Morocco. The principal finding is that even when locals appear well-positioned to reap the ex post benefits of a Bioprospecting success, one can reject the hypothesis that successful Bioprospecting fuels local development and reduces poverty. Most locals participate only superficially in the Bioprospecting-based boom and the benefits that do trickle down to local households appear to be regressively distributed, both regionally and between households. The key lies in understanding how opening up to new markets may induce endogenous product differentiation that easily excludes locals, especially the poor, and how ex ante market access - a variable commonly directly related to wealth - conditions households' capacity to participate in market-induced producer windfalls.
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Is Bioprospecting a viable strategy for conserving tropical ecosystems
Ecological Economics, 2000Co-Authors: Christopher B. Barrett, Travis J. LybbertAbstract:Many prominent scientists avidly advocate bio-prospecting, the systematic search for new com-mercial applications for biota, especially hithertounstudied species, as a mechanism for inducingtropical biodiversity conservation by making itcommercially attractive (Wilson, 1992; Reid et al.,1993; PAHO, 1996; Weiss and Eisner, 1998). Bio-prospecting’s premise is that nature contains hid-den assets of potentially huge, yet unknownmagnitude to humankind that can motivate andeven finance biodiversity conservation in the trop-ics. This undiscovered genetic or biochemical in-formation is commonly framed in the context ofpotential improvements in medicine or food, thusdefining a massive global population of potentialbeneficiaries. It is further argued that bioprospect-ing can affect social and economic development indeveloping countries by rewarding biota-rich butincome-poor tropical communities that preserveand wisely manage their genetic resources. Thepremise of Bioprospecting, coupled with the claimthat practically all of humankind stands tobenefit, and perhaps most especially the poorestof the poor, naturally leads to an urgent desire toconserve tropical biodiversity in order to enablediscovery, extraction, and value-adding transfor-mation of tropical biota.Specifically, it is claimed that Bioprospectingstimulates conservation through two mechanisms.First, Bioprospecting firms should be willing topay to preserve biodiversity for its innovationoption value since they stand to reap direct finan-cial benefits from any marketable discoveries. Sec-ond, conditional on an increase in life sciencesfirms’ willingness to pay for conservation, localinhabitants’ and landholders’ valuation of biodi-versity will change to the extent that they, asstewards over biodiverse habitats, are compen-sated for their contribution to Bioprospecting ac-tivities. To date, most attention with respect to
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Is Bioprospecting a Viable Strategy for Conserving Tropical Ecosystems
1999Co-Authors: Christopher B. Barrett, Travis J. LybbertAbstract:Many prominent scientists avidly advocate Bioprospecting, the systematic search for new commercial applications for biota, especially hitherto unstudied species, as a mechanism for inducing tropical biodiversity conservation by making it commercially attractive (Wilson; Reid et al., 1993; PAHO, 1996 and Weiss). Bioprospecting’s premise is that nature contains hidden assets of potentially huge, yet unknown magnitude to humankind that can motivate and even finance biodiversity conservation in the tropics. This undiscovered genetic or biochemical information is commonly framed in the context of potential improvements in medicine or food, thus defining a massive global population of potential beneficiaries. It is further argued that Bioprospecting can affect social and economic development in developing countries by rewarding biota-rich but income-poor tropical communities that preserve and wisely manage their genetic resources. The premise of Bioprospecting, coupled with the claim that practically all of humankind stands to benefit, and perhaps most especially the poorest of the poor, naturally leads to an urgent desire to conserve tropical biodiversity in order to enable discovery, extraction, and value-adding transformation of tropical biota.
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Is Bioprospecting A Viable Strategy for Conserving Tropical Ecosystems
1999Co-Authors: Christopher B. Barrett, Travis J. LybbertAbstract:This paper explores whether Bioprospecting can reasonably be expected to change rural incentives to conserve tropical ecosystems. Bioprospecting advocates posit that the prospect of discovery ofbiota of immense commercial worth offers an avenue to increase the valuation of nature and endogenously reduce consumptive use of habitat. We consider the microeconomic mechanisms by which Bioprospecting might affect incentives and the distributional consequences of these effects.
Arthur A. Small - One of the best experts on this subject based on the ideXlab platform.
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Valuing Research Leads: Bioprospecting and the Conservation of Genetic Resources
2000Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the "marginal unit" of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute-force testing, unaided by an organizing scientific framework. Scientific models channel research effort towards leads for which the exepected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery, and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to support market-based conservation of biodiversity.
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Valuing Research Leads: Bioprospecting and the Conservation of Genetic Resources
Journal of Political Economy, 2000Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the “marginal unit” of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute‐force testing, unaided by an organizing scientific framework. Scientific models channel research effort toward leads for which the expected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to s...
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Valuing Research Leads: Bioprospecting and the Conservation of Genetic Resources
SSRN Electronic Journal, 2000Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the "marginal unit" of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute-force testing, unaided by an organizing scientific framework. Neither the biological literature nor the behavior of industry actors lends clear support to the contention that natural products prospecting proceeds on the basis of randomized search. Scientific models channel research effort towards leads for which the expected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery, and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to support market-based conservation of biodiversity. The results call into question the conclusions of earlier analyses that had argued that biodiversity prospecting offers no hope as a meaningful source of finance for biodiversity conservation.
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Bioprospecting with Prior Ecological Information
1999Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the marginal unit of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute-force testing, unaided by an organizing scientific framework. Scientific models channel research effort towards leads for which the expected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery, and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to support market-based conservation of biodiversity.
Gordon C. Rausser - One of the best experts on this subject based on the ideXlab platform.
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Valuing Research Leads: Bioprospecting and the Conservation of Genetic Resources
2000Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the "marginal unit" of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute-force testing, unaided by an organizing scientific framework. Scientific models channel research effort towards leads for which the exepected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery, and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to support market-based conservation of biodiversity.
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Valuing Research Leads: Bioprospecting and the Conservation of Genetic Resources
Journal of Political Economy, 2000Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the “marginal unit” of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute‐force testing, unaided by an organizing scientific framework. Scientific models channel research effort toward leads for which the expected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to s...
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Valuing Research Leads: Bioprospecting and the Conservation of Genetic Resources
SSRN Electronic Journal, 2000Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the "marginal unit" of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute-force testing, unaided by an organizing scientific framework. Neither the biological literature nor the behavior of industry actors lends clear support to the contention that natural products prospecting proceeds on the basis of randomized search. Scientific models channel research effort towards leads for which the expected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery, and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to support market-based conservation of biodiversity. The results call into question the conclusions of earlier analyses that had argued that biodiversity prospecting offers no hope as a meaningful source of finance for biodiversity conservation.
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Bioprospecting with Prior Ecological Information
1999Co-Authors: Gordon C. Rausser, Arthur A. SmallAbstract:Bioprospecting has been touted as a source of finance for biodiversity conservation. Recent work has suggested that the Bioprospecting value of the marginal unit of genetic resources is likely to be vanishingly small, creating essentially no conservation incentive. This result is shown to flow specifically from a stylized description of the research process as one of brute-force testing, unaided by an organizing scientific framework. Scientific models channel research effort towards leads for which the expected productivity of discoveries is highest. Leads of unusual promise then command information rents, associated with their role in reducing the costs of search. When genetic materials are abundant, information rents are virtually unaffected by increases in the profitability of product discovery, and decline as technology improvements lower search costs. Numerical simulation results suggest that, under plausible conditions, the Bioprospecting value of certain genetic resources could be large enough to support market-based conservation of biodiversity.
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Bioprospecting with Patent Races
1998Co-Authors: Gordon C. Rausser, Small. A.a.Abstract:Previous work on Bioprospecting has suggested that the potential market returns to genetic resource conservation are likely to be inconsequential. This article shows that when the buyers of genetic resource options are also competitors in patent races, sellers can extract all the surplus associated with their holdings. Under reasonable conditions, the ex ante return to genetic resource assets will then be determined, not by their marginal contribution to surplus, but by their average contribution. The result implies that several bioeconomic studies reporting large average species values provide credible estimates of the strength of market incentives for biodiversity conservation.