Open Access. Powered by Scholars. Published by Universities.®

Microbiology Commons™

Open Access. Powered by Scholars. Published by Universities.®

2007

Discipline
Institution
Keyword
Publication
Publication Type

Articles 121 - 150 of 161

Full-Text Articles in Microbiology

Role Of Mhc Antigens And Immunoregulation In Graft Survival In Autoimmunity, Bhagirath Singh Jan 2007

Role Of Mhc Antigens And Immunoregulation In Graft Survival In Autoimmunity, Bhagirath Singh

Microbiology & Immunology Publications

Using a syngeneic islet transplantation model system we have showed that in autoimmune type 1 diabetes transplanted islets are destroyed by the host immune system unless the transplanted islets lack class I major histocompatibility complex (MHC) molecules. Alternatively, immunomodulation of the host by induction of regulatory T cells prevented the destruction of autologous islet graft. We conclude that these approaches will allow successful transplantation of autologous islets derived from the host by stem cell or other technology without immunosuppression to reverse autoimmune type 1 diabetes.

Go to article

Morphological And Molecular Analyses Of Microorganisms In Caribbean Reef Adult Sponges And In Corresponding Reproductive Material, Susanne Schmitt, Markus Wehrl, Niels Lindquist, Jeremy B. Weisz, Ute Hentschel Jan 2007

Morphological And Molecular Analyses Of Microorganisms In Caribbean Reef Adult Sponges And In Corresponding Reproductive Material, Susanne Schmitt, Markus Wehrl, Niels Lindquist, Jeremy B. Weisz, Ute Hentschel

Faculty Publications

Caribbean reef sponges were surveyed for the presence of microorganisms in the mesohyl tissue of adult sponges and the respective reproductive material (embryos, larvae). A clear correlation was found in that high microbial abundance (HMA) sponges always contained microorganisms in their reproductive stages. In contrast, low microbial abundance (LMA) sponges did not contain microorganisms in their reproductive stages. Based on these data, Ircinia felix Duchassaing and Michelotti, 1864 was chosen as a model organism for the molecular analysis of microorganisms within the adult sponge and its larvae and juveniles. Denaturing gradient gel electrophoresis (DGGE) of eubacterial 16S rDNA sequences revealed …

Go to article

Vertical Transmission Of A Phylogenetically Complex Microbial Consortium In The Viviparous Sponge Ircinia Felix, Susanne Schmitt, Jeremy B. Weisz, Niels Lindquist, Ute Hentschel Jan 2007

Vertical Transmission Of A Phylogenetically Complex Microbial Consortium In The Viviparous Sponge Ircinia Felix, Susanne Schmitt, Jeremy B. Weisz, Niels Lindquist, Ute Hentschel

Faculty Publications

Many marine demosponges contain large amounts of phylogenetically complex yet highly sponge-specific microbial consortia within the mesohyl matrix, but little is known about how these microorganisms are acquired by their hosts. Settlement experiments were performed with the viviparous Caribbean demosponge Ircinia felix to investigate the role of larvae in the vertical transmission of the sponge-associated microbial community. Inspections by electron microscopy revealed large amounts of morphologically diverse microorganisms in the center of I. felix larvae, while the outer rim appeared to be devoid of microorganisms. In juveniles, microorganisms were found between densely packed sponge cells. Denaturing gradient gel electrophoresis (DGGE) …

Go to article

Poxviral B1 Kinase Overcomes Barrier To Autointegration Factor, A Host Defense Against Virus Replication, Matthew S. Wiebe, Paula Traktman Jan 2007

Poxviral B1 Kinase Overcomes Barrier To Autointegration Factor, A Host Defense Against Virus Replication, Matthew S. Wiebe, Paula Traktman

Nebraska Center for Virology: Faculty Publications

Barrier to autointegration factor (BAF) is a DNA-binding protein found in the nucleus and cytoplasm of eukaryotic cells that functions to establish nuclear architecture during mito-sis. Herein, we demonstrate a cytoplasmic role for BAF in host defense during poxviral infections. Vaccinia is the prototypic poxvirus, a family of DNA viruses that replicate ex-clusively in the cytoplasm of infected cells. Mutations in the vaccinia B1 kinase (B1) com-promise viral DNA replication, but the mechanism by which B1 achieves this has remained elusive. We now show that BAF acts as a potent inhibitor of poxvirus replication unless its DNA-binding activity is blocked …

Go to article

Environmental Controls On The Landscape-Scale Biogeography Of Stream Bacterial Communities, Noah Fierer, Jennifer L. Morse, Sean T. Berthrong, Emily S. Bernhardt, Robert B. Jackson Jan 2007

Environmental Controls On The Landscape-Scale Biogeography Of Stream Bacterial Communities, Noah Fierer, Jennifer L. Morse, Sean T. Berthrong, Emily S. Bernhardt, Robert B. Jackson

Scholarship and Professional Work - LAS

We determined the biogeographical distributions of stream bacteria and the biogeochemical factors that best explained heterogeneity for 23 locations within the Hubbard Brook watershed, a 3000-ha forested watershed in New Hampshire, USA. Our goal was to assess the factor, or set of factors, responsible for generating the biogeographical patterns exhibited by microorganisms at the landscape scale. We used DNA fingerprinting to characterize bacteria inhabiting fine benthic organic matter (FBOM) because of their important influence on stream nutrient dynamics. Across the watershed, streams of similar pH had similar FBOM bacterial communities. Streamwater pH was the single variable most strongly correlated with …

Go to article

Sulfur-Oxidizing Bacteria In Soap Lake (Washington State), A Meromictic, Haloalkaline Lake With An Unprecedented High Sulfide Content, Dimitry Y. Sorokin, Mirjam Foti, Holly C. Pinkart, Gerard Muyzer Jan 2007

Sulfur-Oxidizing Bacteria In Soap Lake (Washington State), A Meromictic, Haloalkaline Lake With An Unprecedented High Sulfide Content, Dimitry Y. Sorokin, Mirjam Foti, Holly C. Pinkart, Gerard Muyzer

All Faculty Scholarship for the College of the Sciences

Culture-dependent and -independent techniques were used to study the diversity of chemolithoautotrophic sulfur-oxidizing bacteria in Soap Lake (Washington State), a meromictic, haloalkaline lake containing an unprecedentedly high sulfide concentration in the anoxic monimolimnion. Both approaches revealed the dominance of bacteria belonging to the genus Thioalkalimicrobium, which are common inhabitants of soda lakes. A dense population of Thioalkalimicrobium (up to 107 cells/ml) was found at the chemocline, which is characterized by a steep oxygen-sulfide gradient. Twelve Thioalkalimicrobium strains exhibiting three different phenotypes were isolated in pure culture from various locations in Soap Lake. The isolates fell into two groups …

Go to article

Aids-Associated Viral Oncogenesis: Overview, Charles Wood Jan 2007

Aids-Associated Viral Oncogenesis: Overview, Charles Wood

Nebraska Center for Virology: Faculty Publications

It has been 25 years since the acquired immunodeficiency syndrome (AIDS) was first described and over 23 years since the human immunodeficiency virus (HIV) associated with the disease was first discovered. In spite of the tremendous progress that was made in understanding both the disease and the virus, there are still millions of people infected, died, or living with the disease. As for the year 2005 alone, the Joint United Nations Programme on HIV/AIDS (http://www.UNAIDS.org) estimates that there are about 40 million people living with HIV/AIDS globally, and approximately 3 million people died from AIDS in the year. Globally, it …

Go to article

Modulation Of Retroviral Restriction And Proteasome Inhibitor-Resistant Turnover By Changes In The Trim5Α B-Box 2 Domain, Felipe Diaz-Griffero, Alak Kar, Michel Perron, Shi-Hua Xiang, Hassan Javanbakht, Xing Li, Joseph Sodroski Jan 2007

Modulation Of Retroviral Restriction And Proteasome Inhibitor-Resistant Turnover By Changes In The Trim5Α B-Box 2 Domain, Felipe Diaz-Griffero, Alak Kar, Michel Perron, Shi-Hua Xiang, Hassan Javanbakht, Xing Li, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

An intact B-box 2 domain is essential for the antiretroviral activity of TRIM5α. We modeled the structure of the B-box 2 domain of TRIM5α based on the existing three-dimensional structure of the B-box 2 domain of human TRIM29. Using this model, we altered the residues predicted to be exposed on the surface of this globular structure. Most of the alanine substitutions in these residues exerted little effect on the antiretroviral activity of human TRIM5αhu or rhesus monkey TRIM5αrh. However, alteration of arginine 119 of TRIM5αhu or the corresponding arginine 121 of TRIM5αrh diminished the abilities of …

Go to article

Viral Diseases Of The Fetus, Clayton L. Kelling Jan 2007

Viral Diseases Of The Fetus, Clayton L. Kelling

Nebraska Center for Virology: Faculty Publications

Bovine viral diarrhea virus (BVDV) is one of the most commonly encountered and economically important pathogens of cattle in North America. Since the mid-20th century, BVDV has been recognized as a significant cause of disease of the gastrointestinal system. The impact of BVDV on reproduction was not perceived for another 30 years, when the occurrence of persistent infection in imunotolerant cattle was described.

BVDV infections may occur in cattle as acute illness- that is, bovine viral diarrhea (BVD)-or as a generally chronic condition-mucosal disease. When susceptible regnant cattle are infected with BVDV, transplacental infections usually occur. Transplacental infections may lead …

Go to article

Prion Interference Is Due To A Reduction In Strain-Specific PrpSc Levels, Jason C. Bartz, Michelle L. Kramer, Meghan H. Sheehan, Jessica A. L. Hutter, Jacob I. Ayers, Richard A. Bessen, Anthony E. Kincaid Jan 2007

Prion Interference Is Due To A Reduction In Strain-Specific PrpSc Levels, Jason C. Bartz, Michelle L. Kramer, Meghan H. Sheehan, Jessica A. L. Hutter, Jacob I. Ayers, Richard A. Bessen, Anthony E. Kincaid

Nebraska Center for Virology: Faculty Publications

When two prion strains infect a single host, one strain can interfere with the ability of the other to cause disease but it is not known whether prion replication of the second strain is also diminished. To further investigate strain interference, we infected hamsters in the sciatic nerve with the long-incubation-period transmissible mink encephalopathy (TME) agent DY TME prior to superinfection of hamsters with the short-incubation-period HY TME agent. Increases in the interval between TME agent inoculations resulted in an extension of the incubation period of HY TME or a complete block of the ability of the HY TME agent …

Go to article

Traditional Practices And Exposure To Bodily Fluids In Lusaka, Zambia, Janet M. Wojcicki, Chipepo Kankasa, Charles Mitchell, Charles Wood Jan 2007

Traditional Practices And Exposure To Bodily Fluids In Lusaka, Zambia, Janet M. Wojcicki, Chipepo Kankasa, Charles Mitchell, Charles Wood

Papers in Virology

Objectives To ascertain if there are specific sociocultural and behavioral practices associated with the exposure to saliva, semen and vaginal fluids, particularly through child-rearing practices and the use of traditional medicine in Lusaka, Zambia. Methods We conducted 11 focus group discussions with men and women from diverse ethnic and socioeconomic backgrounds (n = 105) in Lusaka, Zambia in March 2004. We also conducted a brief sociodemographic survey of all focus group participants. Results Discussions indicated that saliva was used while engaging in home health care practices associated with childcare and the use of traditional medicine. Additionally, semen and vaginal …

Go to article

Design Of A Bioreactor To Study The Role Of Red Blood Cells In The Transport Of Nitric Oxide In The Microcirculation, Nupura Bhise, Mahendra Kavdia Jan 2007

Design Of A Bioreactor To Study The Role Of Red Blood Cells In The Transport Of Nitric Oxide In The Microcirculation, Nupura Bhise, Mahendra Kavdia

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Nitric oxide (NO) plays an important role in physiological functions like vasodilation, neurotransmission, and inhibition of platelet aggregation. The endothelium-derived NO diffuses into the vascular lumen where it interacts with flowing blood as well as the smooth muscles where it modulates vascular tone. However, uncertainty exists on how NO escapes the rapid scavenging by hemoglobin (Hb) and reaches smooth muscles. Several proposed hypotheses include 1) a reduced reaction rate of NO with Hb contained inside red blood cells (RBCs) and 2) NO preservation in the bound form of s-nitrosohemoglobin or nitrite. The mechanism and magnitude of reduction of NO reaction …

Go to article

Extending And Measuring The Quality Of Fresh-Cut Fruit And Vegetables: A Review, Ana Belen Martin-Diana, Daniel Rico, Gary Henehan, Jesus Maria Frias, J. Barat Jan 2007

Extending And Measuring The Quality Of Fresh-Cut Fruit And Vegetables: A Review, Ana Belen Martin-Diana, Daniel Rico, Gary Henehan, Jesus Maria Frias, J. Barat

Articles

The market sales of ready - to - use vegetables have grown rapidly in recent decades as a result of changes in consumer attitudes especially consumption of fresh-cut lettuce and carrot due to their use in prepared salads. Chlorine solutions have been widely used to sanitise fruit and vegetables in the fresh-cut industry. However, the association of chlorine with the possible formation of carcinogenic chlorinated compounds in water has called into question the use of chlorine in food processing. There is a real need to find alternatives for preservation of fresh-cut fruit and vegetables in order to improve the efficacy …

Go to article

Humboldt Journal Of Microbiology: Volume 9, Number 1- May 2007, Press Humboldt Jan 2007

Humboldt Journal Of Microbiology: Volume 9, Number 1- May 2007, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.

Go to article

Comparison Study Of The Averaged Sediment Microbial Enzyme Activities In Four Fecally-Contaminated Streams In The Same Watershed In Northeast Tennessee To Biochemical Oxygen Demand, Nitrate Concentration, And Phosphate Concentration, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman Jan 2007

Comparison Study Of The Averaged Sediment Microbial Enzyme Activities In Four Fecally-Contaminated Streams In The Same Watershed In Northeast Tennessee To Biochemical Oxygen Demand, Nitrate Concentration, And Phosphate Concentration, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman

ETSU Faculty Works

Microbial enzyme activities (MEA’s) are measurements of microbial metabolism. These activities are dependent on the need for nutrients and respiration. This extended study evaluated four streams in the same watershed that had an approved fecal coliform Total Maximum Daily Load. Sediment and water samples were collected monthly for the first year of each specific stream study, and then quarterly to the end of 2006. Dehydrogenase, a measure of microbial respiration, along with acid phosphatase, alkaline phosphatase, galactosidase and glucosidase activities were measured using colorimetric assays. Biochemical oxygen demand (BOD) was determined using the standard 5-day test (BOD5). Nitrate …

Go to article

Evaluation Of Four Novel Broad-Host-Range Antimicrobial Agents., Jiahui Guo Jan 2007

Evaluation Of Four Novel Broad-Host-Range Antimicrobial Agents., Jiahui Guo

Theses

The overall objective of this thesis was to evaluate the antimicrobial effects of four novel broad-host-range antimicrobial agents. The first was a milk-derived lipoprotein developed by Westgate Biologicals with the support of Enterprise Ireland. This lipoprotein which was designated LactiSAL, was evaluated against a wide range of bacterial species associated with humans. Essentially, the LactiSAL was incorporated at a variety of concentrations into agar media, which were appropriate for cultivation of the different genera. Agars were examined for colony formation, after which it was possible to quantify the minimal inhibitory concentration for each genus. Subsequently, LactiSAL was incorporated at levels …

Go to article

Hypoxic Induction And The Role Of Hifs In The Activation Of Luciferase Constitutive Reporters In Placental Stem Cells, Diane Michelle Doran Jan 2007

Hypoxic Induction And The Role Of Hifs In The Activation Of Luciferase Constitutive Reporters In Placental Stem Cells, Diane Michelle Doran

Browse all Theses and Dissertations

Hypoxia is critically important to the development of the embryo and placenta. Proper placental development is critical for normal fetal growth and embryonic survival. Abnormal placental development has been implicated in numerous obstetric complications, including preeclampsia, which affects about 7% of all pregnancies and can be fatal for both mother and baby. Rodent and murine trophoblast stem cells differentiate into three distinct cell lineages: giant cells, spongiotrophoblasts, and labyrinthine cells, which form different layers and have different functions within the placenta. Recent studies in our laboratory have focused on the invasive giant cell layer using the rodent Rcho-1 choriocarcinoma stem …

Go to article

On A Multinational Assessment Of Rotavirus Disease In Europe, David O. Matson Jan 2007

On A Multinational Assessment Of Rotavirus Disease In Europe, David O. Matson

Community & Environmental Health Faculty Publications

Rotaviruses were discovered in the 1960s in animals and in the 1970s in humans; the latter discovery was made by an intrepid group who performed duodenal biopsies on children with acute gastroenteritis (AGE) [1]. By the late 1970s, data already clearly indicated that rotavirus was the cause of the annual winter peak of AGE affecting young children, as well as a frequent cause of severe gastroenteritis in various animal species (e.g., [2–5]). Use of the retrospectroscope clarified or left as tantalizing the suggestion that rotaviruses were the cause of the annual “winter vomiting syndrome” first described in children in 1910 …

Go to article

Potential For Stimulating Host Anti-Tumor Immune Response Via Rnai-Mediated Local Foxp3 Knockdown, N. Klaiber Jan 2007

Potential For Stimulating Host Anti-Tumor Immune Response Via Rnai-Mediated Local Foxp3 Knockdown, N. Klaiber

Chemistry & Biochemistry Faculty Publications

Neoplastic growths represent a unique challenge for the host immune system. As they are indeed derived from self, many of the same mechanisms operating to prevent autoimmunity also provide an umbrella beneath which malignant cells are free to proliferate.1 Central among these immune regulatory boundaries are an influential subset of lymphocytes known as T regs. Hypothesized to exist decades ago, yet eluding definitive characterization until relatively recently, T regs have been demonstrated to play a crucial role in the proper functioning of the immune system as a whole. They may also, however, represent one of the primary obstacles to successful …

Go to article

Mutations In Transmembrane Domains 1, 4 And 9 Of The Plasmodium Falciparum Chloroquine Resistance Transporter Alter Susceptibility To Chloroquine, Quinine And Quinidine, Roland A. Cooper, Kristan D. Lane, Bingbing Deng, Jianbing Mu, Jigar J. Patel, Thomas E. Wellems, Xinzhuan Su, Michael T. Ferdig Jan 2007

Mutations In Transmembrane Domains 1, 4 And 9 Of The Plasmodium Falciparum Chloroquine Resistance Transporter Alter Susceptibility To Chloroquine, Quinine And Quinidine, Roland A. Cooper, Kristan D. Lane, Bingbing Deng, Jianbing Mu, Jigar J. Patel, Thomas E. Wellems, Xinzhuan Su, Michael T. Ferdig

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT) can result in verapamil-reversible CQ resistance and altered susceptibility to other antimalarials. PfCRT contains 10 membrane-spanning domains and is found in the digestive vacuole (DV) membrane of intraerythrocytic parasites. The mechanism by which PfCRT mediates CQ resistance is unclear although it is associated with decreased accumulation of drug within the DV. On the permissive background of the P. falciparum 106/1(K76) parasite line, we used single-step drug selection to generate isogenic clones containing unique pfcrt point mutations that resulted in amino acid changes in PfCRT transmembrane domains 1 (C72R, K76N, K76I …

Go to article

Sensory Genes And Mate Choice: Evidence That Duplications, Mutations, And Adaptive Evolution Alter Variation In Mating Cue Genes And Their Receptors, Lisa Horth Jan 2007

Sensory Genes And Mate Choice: Evidence That Duplications, Mutations, And Adaptive Evolution Alter Variation In Mating Cue Genes And Their Receptors, Lisa Horth

Biological Sciences Faculty Publications

Fascinating new data, revealed through gene sequencing, comparative genomics, and genetic engineering, precisely establish which genes are involved in mate choice and mating activity—behaviors that are surprisingly understudied from a genetic perspective. Discussed here are some of the recently identified visual and chemosensory genes that are involved in mate choice and mating behavior. These genes’ products are involved in the production, transmission, and receipt of crucial sensory mate-choice cues that affect fitness. This review exposes newfound evidence that alternative splicing, gene-expression pattern changes, and molecular genetic variation in sensory genes are crucial for both intra- and interspecific mate choice and …

Go to article

Design, Synthesis, And Evaluation Of 10-N-Substituted Acridones As Novel Chemosensitizers In Plasmodium Falciparum, Jane X. Kelly, Martin J. Smilkstein, Roland A. Cooper, Kristin D. Lane, Robert A. Johnson, Aaron Janowsky, Rozalia A. Dodean, David J. Hinrichs, Rolf Winter, Michael Riscoe Jan 2007

Design, Synthesis, And Evaluation Of 10-N-Substituted Acridones As Novel Chemosensitizers In Plasmodium Falciparum, Jane X. Kelly, Martin J. Smilkstein, Roland A. Cooper, Kristin D. Lane, Robert A. Johnson, Aaron Janowsky, Rozalia A. Dodean, David J. Hinrichs, Rolf Winter, Michael Riscoe

Biological Sciences Faculty Publications

A series of novel 10-N-substituted acridones, bearing alkyl side chains with tertiary amine groups at the terminal position, were designed, synthesized, and evaluated for the ability to enhance the potency of quinoline drugs against multidrug-resistant (MDR) Plasmodium falciparum malaria parasites. A number of acridone derivatives, with side chains bridged three or more carbon atoms apart between the ring nitrogen and terminal nitrogen, demonstrated chloroquine (CQ)-chemosensitizing activity against the MDR strain of P. falciparum (Dd2). Isobolograrn analysis revealed that selected candidates demonstrated significant synergy with CQ in the CQ-resistant (CQR) parasite Dd2 but only additive (or indifferent) interaction in the CQ-sensitive …

Go to article

Chemical Defenses: From Compounds To Communities, Valerie J. Paul, Koty H. Sharp Jan 2007

Chemical Defenses: From Compounds To Communities, Valerie J. Paul, Koty H. Sharp

Arts & Sciences Faculty Publications

Marine natural products play critical roles in the chemical defense of many marine organisms and in some cases can influence the community structure of entire ecosystems. Although many marine natural products have been studied for biomedical activity, yielding important information about their biochemical effects and mechanisms of action, much less is known about ecological functions. The way in which marine consumers perceive chemical defenses can influence their health and survival and determine whether some natural products persist through a food chain. This article focuses on selected marine natural products, including okadaic acid, brevetoxins, lyngbyatoxin A, caulerpenyne, bryostatins, and isocyano terpenes, …

Go to article

Characteristics Of A Foamy Virus-Derived Vector That Allow For Safe Autologous Gene Therapy To Correct Leukocyte Adhesion Deficiency Type 1, Ryan Matthew Mcnichol Jan 2007

Characteristics Of A Foamy Virus-Derived Vector That Allow For Safe Autologous Gene Therapy To Correct Leukocyte Adhesion Deficiency Type 1, Ryan Matthew Mcnichol

Browse all Theses and Dissertations

The hematopoeitic stem cell is a prime target for gene therapy in the attempt to correct a number of single gene inherited genetic defects that affect the immune system. In persons affected by leukocyte adhesion deficiency type 1 (LAD-1) the gene for the Beta-2 subunit of the integrin molecule is mutated. This autosomal recessive gene defect yields a phenotype with little or no beta-2 integrin expression on leukocytes. Beta-2 integrin expression is essential for leukocytes to travel from the blood to the tissues to fight infection. Persons with this disease have lowered leukocyte counts in the tissues and as a …

Go to article

Hsv-1 Infection Of C3h Central Nervous System Cell Lines, Lauren Kay Van Buren Jan 2007

Hsv-1 Infection Of C3h Central Nervous System Cell Lines, Lauren Kay Van Buren

Browse all Theses and Dissertations

Herpes Simplex Virus Type 1 (HSV-1) can infect the nervous system, resulting in a disease known as herpes encephalitis (HSE). Herpes encephalitis affects thousands of people each year; many cases are fatal or permanently debilitating. Approximately two thousand known cases occur in the United States each year alone (Neuroland online source). Acyclovir has been the drug of choice used to treat herpes encephalitis. Even after the administration of acyclovir, permanent neurological damage and/or death often results. Thousands of individuals would benefit by the discovery of drugs that are more effective at preventing lasting HSE damage and death. Knowledge concerning HSE …

Go to article

Discovery Of New Antimicrobial Agents Using Combinatorial Chemistry, William I. Northern Jan 2007

Discovery Of New Antimicrobial Agents Using Combinatorial Chemistry, William I. Northern

Browse all Theses and Dissertations

Combinatorial chemistry has become an important aspect of medicinal research due to its flexibility and the ability to produce large numbers of potential therapeutic agents. Once compounds are made, they must be screened to determine if there is any biological activity. This research project focused on developing a screening method for chemical agents produced by a graduate student in the chemistry department at Wright State University. After an acceptable screening method was found, the goal of the project was to determine if compounds produced had either antibacterial activity, antifungal activity, or both. Seven compounds exhibited biological activity. Two of these …

Go to article

Structural Definition Of A Conserved Neutralization Epitope On Hiv-1 Gp120, Tongqing Zhou, Ling Xu, Barna Dey, Ann J. Hessell, Donald Van Ryk, Shi-Hua Xiang, Xinzhen Yang, Mei-Yun Zhang, Michael B. Zwick, James Arthos, Dennis R. Burton, Dimiter S. Dimitrov, Joseph Sodroski, Richard Wyatt, Gary J. Nabel, Peter D. Kwong Jan 2007

Structural Definition Of A Conserved Neutralization Epitope On Hiv-1 Gp120, Tongqing Zhou, Ling Xu, Barna Dey, Ann J. Hessell, Donald Van Ryk, Shi-Hua Xiang, Xinzhen Yang, Mei-Yun Zhang, Michael B. Zwick, James Arthos, Dennis R. Burton, Dimiter S. Dimitrov, Joseph Sodroski, Richard Wyatt, Gary J. Nabel, Peter D. Kwong

Nebraska Center for Virology: Faculty Publications

The remarkable diversity, glycosylation and conformational flexibility of the human immunodeficiency virus type 1 (HIV-1) envelope (Env), including substantial rearrangement of the gp120 glycoprotein upon binding the CD4 receptor, allow it to evade antibody-mediated neutralization. Despite this complexity, the HIV-1 Env must retain conserved determinants that mediate CD4 binding. To evaluate how these determinants might provide opportunities for antibody recognition, we created variants of gp120 stabilized in the CD4-bound state, assessed binding of CD4 and of receptor-binding-site antibodies, and determined the structure at 2.3Å resolution of the broadly neutralizing antibody b12 in complex with gp120. b12 binds to a conformationally …

Go to article

Structures Of The Ccr5 N Terminus And Of A Tyrosine-Sulfated Antibody With Hiv-1 Gp120 And Cd4, Chih-Chin Huang, Son N. Lam, Priyamvada Acharya, Min Tang, Shi-Hua Xiang, Syed Shahzad-Ul Hussan, Robyn L. Stanfield, James Robinson, Ian A. Wilson, Richard Wyatt, Carole A. Bewley, Peter D. Kwong Jan 2007

Structures Of The Ccr5 N Terminus And Of A Tyrosine-Sulfated Antibody With Hiv-1 Gp120 And Cd4, Chih-Chin Huang, Son N. Lam, Priyamvada Acharya, Min Tang, Shi-Hua Xiang, Syed Shahzad-Ul Hussan, Robyn L. Stanfield, James Robinson, Ian A. Wilson, Richard Wyatt, Carole A. Bewley, Peter D. Kwong

Nebraska Center for Virology: Faculty Publications

The CCR5 co-receptor binds to the HIV-l gp120 envelope glycoprotein and facilitates HIV-l entry into cells. Its N terminus is tyrosine-sulfated, as are many antibodies that react with the co-receptor binding site on gp120. We applied nuclear magnetic resonance and crystallographic techniques to analyze the structure of the CCR5 N terminus and that of the tyrosine-sulfated antibody 412d in complex with gp120 and CD4. The conformations of tyrosine-sulfated regions of CCR5 (α-helix) and 412d (extendedloop) are surprisingly different. Nonetheless, a critical sulfotyrosine on CCR5 and on 412d induces similar structural rearrangements in gp120. These results now provide a framework for …

Go to article

Functional Interplay Between The B-Box 2 And The B30.2(Spry) Domains Of Trim5Α, Xi Ling, Byeongwoon Song, Shi-Hua Xiang, Joseph Sodroski Jan 2007

Functional Interplay Between The B-Box 2 And The B30.2(Spry) Domains Of Trim5Α, Xi Ling, Byeongwoon Song, Shi-Hua Xiang, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

The retroviral restriction factors, TRIM5α and TRIMCyp, consist of RING and B-box 2 domains separated by a coiled coil from carboxy-terminal domains. These carboxy-terminal domains (the B30.2(SPRY) domain in TRIM5α and the cyclophilin A domain in TRIMCyp) recognize the retroviral capsid. Here we show that some B-box 2 changes in TRIM5α, but not in TRIMCyp, resulted in decreased human immunodeficiency virus (HIV-1) capsid binding. The phenotypic effects of these B-box 2 changes on the restriction of retroviral infection depended on the potency of restriction and the affinity of the TRIM5α interaction with the viral capsid, two properties specified by the …

Go to article

Characterization Of Human Immunodeficiency Virus Type 1 Monomeric And Trimeric Gp120 Glycoproteins Stabilized In The Cd4-Bound State: Antigenicity, Biophysics, And Immunogenicity, Barna Dey, Marie Pancera, Krisha Svehla, Yuuei Shu, Shi-Hua Xiang, Jeffrey Vainshtein, Yuxing Li, Joseph Sodroski, Peter D. Kwong, John R. Mascola, Richard Wyatt Jan 2007

Characterization Of Human Immunodeficiency Virus Type 1 Monomeric And Trimeric Gp120 Glycoproteins Stabilized In The Cd4-Bound State: Antigenicity, Biophysics, And Immunogenicity, Barna Dey, Marie Pancera, Krisha Svehla, Yuuei Shu, Shi-Hua Xiang, Jeffrey Vainshtein, Yuxing Li, Joseph Sodroski, Peter D. Kwong, John R. Mascola, Richard Wyatt

Nebraska Center for Virology: Faculty Publications

The human immunodeficiency virus type 1 exterior gp120 envelope glycoprotein is highly flexible, and this flexibility may contribute to the inability of monomeric gp120 immunogens to elicit broadly neutralizing antibodies. We previously showed that an S375W modification of a critical interfacial cavity central to the primary receptor binding site, the Phe43 cavity, stabilizes gp120 into the CD4-bound state. However, the immunological effects of this cavity-altering replacement were never tested. Subsequently, we screened other mutations that, along with the S375W alteration, might further stabilize the CD4-bound state. Here, we define a selected second cavity-altering replacement, T257S, and analyze the double mutations …

Go to article

First Prev Next Last