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Process Design for the Biocatalysis of Value-Added Chemicals from Carbon Dioxide

Description: This report describes results toward developing a process to sequester CO{sub 2} centered on the enzyme pyruvate carboxylase. The process involves the use of bacteria to convert CO{sub 2} and glucose as a co-substrate and generates succinic acid as a commodity chemical product. The first phase of this research has focused on strain development and on process development. Progress in strain development has been made in three areas. The gene encoding for alcohol dehydrogenase has been ''knocked out'' of the bacteria, and thereby eliminating the synthesis of the by-product ethanol. The gene for glucokinase has been overexpressed in the production strain with the goal of faster utilization of glucose (and hence CO{sub 2}). Efforts have continued toward integrating pyruvate carboxylase gene (pyc) onto the E. coli chromosome. Progress in process development has come in conducting several dozen fermentation experiments to find a defined medium that would be successful for the growth of the bacteria, while permitting a high rate of CO{sub 2} utilization in a subsequent prolonged production phase. Using this defined medium, the strains that continue to be constructed are being compared for CO{sub 2} utilization, so that we may understand the factors that govern the biological sequestration process.
Date: November 1, 2005
Creator: Eiteman, Mark A.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Structures and Functions of Oligosaccharins

Description: We have made considerable progress during the 2.5 year funding period just ending in our studies of the structures and functions of oligosaccharide signal molecules (oligosaccharins). We have emphasized studies of the enzymes that solubilize, process, and degrade oligosaccharins and of the proteins that inhibit those enzymes. We have been especially interested in elucidating how oligosaccharins and their processing enzymes participate in determining the outcome of challenges to plants by pathogenic microbes. We have studied, to a lesser extent, the roles of oligosaccharins in plant growth and development. Abstracts of papers describing results acquired with support from this grant that have been published, submitted, or in preparation are presented to summarize the progress made during the last two and one half years. The report highlights the most important contributions made in our oiigosaccharin research during this time period, and the corresponding abstract is referenced. Results of work in progress are described primarily in conjunction with our application for continued support.
Date: December 1, 1995
Creator: Albersheim, Peter
Item Type: Report
Partner: UNT Libraries Government Documents Department

Fundamental Studies of Recombinant Hydrogenases

Description: This research addressed the long term goals of understanding the assembly and organization of hydrogenase enzymes, of reducing them in size and complexity, of determining structure/function relationships, including energy conservation via charge separation across membranes, and in screening for novel H2 catalysts. A key overall goal of the proposed research was to define and characterize minimal hydrogenases that are produced in high yields and are oxygen-resistant. Remarkably, in spite of decades of research carried out on hydrogenases, it is not possible to readily manipulate or design the enzyme using molecular biology approaches since a recombinant form produced in a suitable host is not available. Such resources are essential if we are to understand what constitutes a “minimal” hydrogenase and design such catalysts with certain properties, such as resistance to oxygen, extreme stability and specificity for a given electron donor. The model system for our studies is Pyrococcus furiosus, a hyperthermophile that grows optimally at 100°C, which contains three different nickel-iron [NiFe-] containing hydrogenases. Hydrogenases I and II are cytoplasmic while the other, MBH, is an integral membrane protein that functions to both evolve H2 and pump protons. Three important breakthroughs were made during the funding period with P. furiosus soluble hydrogenase I (SHI). First, we produced an active recombinant form of SHI in E. coli by the co-expression of sixteen genes using anaerobically-induced promoters. Second, we genetically-engineered P. furiosus to overexpress SHI by an order of magnitude compared to the wild type strain. Third, we generated the first ‘minimal’ form of SHI, one that contained two rather than four subunits. This dimeric form was stable and active, and directly interacted with a pyruvate-oxidizing enzyme with any intermediate electron carrier. The research resulted in five peer-reviewed publications.
Date: January 25, 2014
Creator: Adams, Michael W
Item Type: Report
Partner: UNT Libraries Government Documents Department

Multidisciplinary Graduate Education in Bioprocess Engineering

Description: This report describes the accomplishments of the University of Georgia in establishing an academic program geared toward the emerging biobased products industry. By virtue of its strengths and structure, the University of Georgia is particularly well-suited for developing a program focused on plant- and microbial-based bioproducts, and it was in this general area that this program was developed. The program had several unique characteristics. First, we implemented a distinguished lecture series that brought outstanding scientists and engineers to our University to interact with students and share their vision of the biobased economy. Second, we offered industrially-oriented and multidisciplinary courses that provided students with a broad background on various facets of biobased business and technology. Third, we provided the students with opportunities to expand beyond the classroom by engaging in research lab rotations and industrial internships. Fourth, each student was engaged in a creative research project as led by a multidisciplinary faculty team. Throughout the implementation of these activities, we maintained a student-centered, mentoring approach to education. The most tangible outcome of this project was the graduation of two students who participated in a variety of scholarly activities, culminating in research toward the completion of a thesis and dissertation. Both research projects involved the use of microorganisms to produce industrial products from agricultural substrates via fermentation processes. The research advanced our understanding of microorganisms as used for industrial processes and products, as described in several articles published in scholarly journals and presentations made at scientific conferences (see information on pp. 14-15). Another outcome is one graduate course, Fermentation Engineering Laboratory, which is a unique experiential and multidisciplinary course. This course will be offered in the future as an elective to graduate students in several engineering and science degree programs. Other significant developments have arisen as direct or indirect consequences of this ...
Date: April 18, 2006
Creator: Eiteman, Mark A.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Religion and Environmental Crisis

Description: This book is a compilation of papers discussing various aspects of environmental ethics, including information about classical polytheism, Judaism, Christian ecological theology, Taoism, Christian realism.
Date: 1986
Creator: Hargrove, Eugene C.
Item Type: Book
Partner: UNT Libraries

The Engineered Phytoremediation of Ionic and Methylmercury Pollution

Description: Our current specific objectives are to use transgenic plants to control the chemical species, electrochemical state, and above ground binding of mercury to (a) prevent methylmercury from entering the food-chain, (b) remove mercury from polluted sites, and (c) hyperaccumulate mercury in above ground tissues for later harvest.
Date: June 24, 2003
Creator: Meagher, Richard; Marshburn, Sarah; Heaton, Andrew; Zimer, Anne Marie & Rahman, Raoufa
Item Type: Report
Partner: UNT Libraries Government Documents Department

Phytoremediation of Ionic and Methyl Mercury Pollution

Description: Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to control the chemical speciation, electrochemical state, transport, and aboveground ...
Date: June 1, 2005
Creator: Meagher, Richard B.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Phytoremediation of Ionic and Methyl Mercury Pollution

Description: Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to control the chemical speciation, electrochemical state, transport, and aboveground ...
Date: June 1, 2005
Creator: Meagher, Richard B.
Item Type: Report
Partner: UNT Libraries Government Documents Department

A Phytoremediation Strategy for Arsenic

Description: A Phytoremediation Strategy for Arsenic Progress Report May, 2005 Richard B. Meagher Principal Investigator Arsenic pollution affects the health of several hundred millions of people world wide, and an estimated 10 million Americans have unsafe levels of arsenic in their drinking water. However, few environmentally sound remedies for cleaning up arsenic contaminated soil and water have been proposed. Phytoremediation, the use of plants to extract and sequester environmental pollutants, is one new technology that offers an ecologically sound solution to a devastating problem. We propose that it is less disruptive to the environment to harvest and dispose of several thousand pounds per acre of contaminated aboveground plant material, than to excavate and dispose of 1 to 5 million pounds of contaminated soil per acre (assumes contamination runs 3 ft deep). Our objective is to develop a genetics-based phytoremediation strategy for arsenic removal that can be used in any plant species. This strategy requires the enhanced expression of several transgenes from diverse sources. Our working hypothesis is that organ-specific expression of several genes controlling the transport, electrochemical state, and binding of arsenic will result in the efficient extraction and hyperaccumulation of arsenic into aboveground plant tissues. This hypothesis is supported by theoretical arguments and strong preliminary data. We proposed six Specific Aims focused on testing and developing this arsenic phytoremediation strategy. During the first 18 months of the grant we made significant progress on five Specific Aims and began work on the sixth as summarized below. Specific Aim 1: Enhance plant arsenic resistance and greatly expand sinks for arsenite by expressing elevated levels of thiol-rich, arsenic-binding peptides. Hyperaccumulation of arsenic depends upon making plants that are both highly tolerant to arsenic and that have the capacity to store large amounts of arsenic aboveground. Phytochelatins bind diverse thiol-reactive elements like As(III) and ...
Date: June 1, 2005
Creator: Meagher, Richard B.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Phytoremediation of Ionic and Methyl Mercury Pollution

Description: Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems.
Date: December 1, 2004
Creator: Meagher, Richard B.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Integrating the Molecular Machines of Mercury Detoxification into Host Cell Biology

Description: Integrating the Molecular Machines of Mercury Detoxification into Host Cell Biology The bacterial mercury resistance (mer) operon, one of the most evolutionarily successful genetic loci in any defined organism, detoxifies organic and inorganic mercury compounds. Several major biotic processes in the global Hg(II) cycle are carried out by bacteria with this highly mobile detoxification locus that occurs in Gram negative and high and low GC Gram positive bacteria. The functions of many individual mer operon components are well described, so we aim to dissect the higher order interactions of the enzymes, transporters, and regulators of this paradigm metal metabolizing system with each other and with the larger metabolism of the host cell. Understanding how this ubiquitous detoxification system fits into the biology and ecology of its bacterial host is essential to guide interventions that support and enhance Hg remediation. Specifically, we will test the hypotheses that: (a) the organomercurial lyase, MerB, and the mercuric reductase, MerA, act synergistically together and with the membrane-bound Hg(II) transporters, MerT and MerC, to detoxify mercurials; (b) the interaction of the metalloregulator MerR with RNA polymerase (RNAP) and with its DNA binding site, MerO, modulates its metal response, and interaction with its antagonist, MerD, prevents RNA polymerase from binding to the structural gene promoter, P merT and (c) exposure of cells to Hg(II) makes specific demands on cellular resources and expression of the mer operon modulates those demands and is, in turn, modulated by them. To test these hypotheses we propose to: (a) use enzymology, NMR, fluorescence anisotropy, protein-crosslinking, crystallography, and calorimetry in vitro along with in vivo measurements of Hg(II) volatilization and HgR phenotyping to detect and define interactions between the mer enzymes, MerA and MerB, and the transporters, MerT and MerC,and their functional fragments and specific mutant variants; (b) use NMR, fluorescence anisotropy, ...
Date: March 11, 2010
Creator: Summers, Anne O
Item Type: Report
Partner: UNT Libraries Government Documents Department

Quantifying And Predicting Wood Quality Of Loblolly And Slash Pine Under Intensive Forest Management Final Technical Report

Description: The forest industry will increasingly rely on fast-growing intensively managed southern pine plantations to furnish wood and fiber. Intensive silvicultural practices, including competition control, stand density control, fertilization, and genetic improvement are yielding tremendous gains in the quantity of wood production from commercial forest land. How these technologies affect wood properties was heretofore unknown, although there is concern about the suitability of fast-grown wood for traditional forest products. A four year study was undertaken to examine the effects of these intensive practices on the properties of loblolly and slash pine wood by applying a common sampling method over 10 existing field experiments. Early weed control gets young pines off to a rapid start, often with dramatically increased growth rates. This response is all in juvenile wood however, which is low in density and strength. Similar results are found with early Nitrogen fertilization at the time of planting. These treatments increase the proportion of juvenile wood in the tree. Later, mid-rotation fertilization with Nitrogen and Phosphorus can have long term (4-8 year) growth gains. Slight reductions in wood density are short-lived (1-2 years) and occur while the tree is producing dense, stiff mature wood. Impacts of mid-rotation fertilization on wood properties for manufacturing are estimated to be minimal. Genetic differences are evident in wood density and other properties. Single family plantings showed somewhat more uniform properties than bulk improved or unimproved seedlots. Selection of genetic sources with optimal wood properties may counter some of the negative impacts of intensive weed control and fertilization. This work will allow forest managers to better predict the effects of their practices on the quality of their final product.
Date: May 4, 2006
Creator: Daniels, Richard F. & III, Alexander Clark
Item Type: Report
Partner: UNT Libraries Government Documents Department

Environmental Ethics, Volume 10, Number 2, Summer 1988

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1988
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 5, Number 2, Summer 1983

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1983
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 10, Number 1, Spring 1988

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1988
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 5, Number 1, Spring 1983

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1983
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 9, Number 2, Summer 1987

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1987
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 2, Number 4, Winter 1980

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1980
Creator: Environmental Philosophy, Inc.
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 6, Number 1, Spring 1984

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1984
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 2, Number 3, Fall 1980

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1980
Creator: Environmental Philosophy, Inc.
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 3, Number 3, Fall 1981

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1981
Creator: Environmental Philosophy, Inc.
Partner: UNT Center For Environmental Philosophy

Environmental Ethics, Volume 5, Number 4, Winter 1983

Description: Quarterly publication discussing various topics in environmental ethics, including features, discussion papers, book reviews, editorial commentaries, and other text related to environmental philosophies. Some issues also include announcements and other news related to the environmental studies community.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1983
Creator: The Center for Environmental Philosophy
Partner: UNT Center For Environmental Philosophy