Molecular Biology Commons^™

Structure And Dynamics Of Metalloproteins In Live Cells, Jeremy D. Cook, James E. Penner-Hahn, Timothy L. Stemmler

Biochemistry and Molecular Biology Faculty Publications

X-ray absorption spectroscopy (XAS) has emerged as one of the premier tools for investigating the structure and dynamic properties of metals in cells and in metal containing biomolecules. Utilizing the high flux and broad energy range of X-rays supplied by synchrotron light sources, one can selectively excite core electronic transitions in each metal. Spectroscopic signals from these electronic transitions can be used to dissect the chemical architecture of metals in cells, in cellular components and in biomolecules at varying degrees of structural resolution. With the development of ever-brighter X-ray sources, X-ray methods have grown into applications that can be utilized …

Comparison Of Electrically Mediated And Liposome-Complexed Plasmid Dna Delivery To The Skin, Loree C. Heller, Mark J. Jaroszeski, Domenico Coppola, Richard Heller

Bioelectrics Publications

BACKGROUND: Electroporation is an established technique for enhancing plasmid delivery to many tissues in vivo, including the skin. We have previously demonstrated efficient delivery of plasmid DNA to the skin utilizing a custom-built four-plate electrode. The experiments described here further evaluate cutaneous plasmid delivery using in vivo electroporation. Plasmid expression levels are compared to those after liposome mediated delivery.

METHODS: Enhanced electrically-mediated delivery, and less extensively, liposome complexed delivery, of a plasmid encoding the reporter luciferase was tested in rodent skin. Expression kinetics and tissue damage were explored as well as testing in a second rodent model.

RESULTS: Experiments …

Molecular Characterisation Of A Bovine-Like Rotavirus Detected From A Giraffe, Emily Mulherin, Jill Bryan, Marijke Beltman, Luke O'Grady, Eugene Pidgeon, Lucie Garon, Andrew Lloyd, John Bainbridge, Helen O'Shea, Paul Whyte, Séamus Fanning

Department of Biological Sciences Publications

Background

Rotavirus (RV), is a member of the Reoviridae family and an important etiological agent of acute viral gastroenteritis in the young. Rotaviruses have a wide host range infecting a broad range of animal species, however little is known about rotavirus infection in exotic animals. In this paper we report the first characterisation of a RV strain from a giraffe calf.

Results

This report describes the identification and detailed molecular characterisation of a rotavirus strain detected from a 14-day-old Giraffe (Giraffa camelopardalis), presenting with acute diarrhea. The RV strain detected from the giraffe was characterized molecularly as G10P[11]. …

Estimating Kinetic And Thermodynamic Parameters From Single Molecule Enzyme-Inhibitor Interactions, Laura Porter-Peden, Sarah G. Kamper, Mark Vander Wal, Ronald Blankespoor

University Faculty Publications and Creative Works

We report the application of recently developed microscopic models to estimate the apparent kinetic and thermodynamic parameters in a single molecule force spectroscopy study of the carbonic anhydrase enzyme and a complementary sulfonamide inhibitor. The most probable rupture force for the enzyme-inhibitor interaction shows a nonlinear dependency on the log-loading rate. Estimates for the kinetic and thermodynamic parameters were obtained by fitting the nonlinear dependency to linear cubic potential and cusp potential models and compared to the standard Bell-Evans model. The reliability of the estimated parameters was verified by modeling the experimental rupture force distributions by the theoretically predicted distributions …

Dynamics Of Apomyoglobin In The Α-To-Β Transition And Of Partially Unfolded Aggregated Protein, E. Fabiani, A. M. Stadler, D. Madern, M. M. Koza, M. Tehei, M. Hirai, G. Zaccai

Faculty of Science - Papers (Archive)

Changes of molecular dynamics in the α-to-β transition associated with amyloid fibril formation were explored on apo-myoglobin (ApoMb) as a model system. Circular dichroism, neutron and X-ray scattering experiments were performed as a function of temperature on the protein, at different solvent conditions. A significant change in molecular dynamics was observed at the α-to-β transition at about 55 ˚C, indicating a more resilient high temperature β structure phase. A similar effect at approximately the same temperature was observed in holo-myoglobin, associated with partial unfolding and protein aggregation. A study in a wide temperature range between 20 K and 360 K …

Oriented Cell Growth On Self-Assembled Bacteriophage M13 Thin Films, Jianhua Rong, L. Andrew Lee, Kai Li, Brandon Harp, Charlene M. Mello, Zhongwei Niu, Qian Wang

Faculty Publications

Fibrillar M13 bacteriophages were used as basic building blocks to generate thin films with aligned nanogrooves, which, upon chemical grafting with RGD peptides, guide cell alignment and orient the cell outgrowth along defined directions.

Detection Of Biomarkers By Mrs Requires Error Analysis, Jeffrey C. Hoch, Mark W. Maciejewski, Michael R. Gryk

UCHC Articles - Research

Using MRS imaging and singular value decomposition (SVD), Manganas et al. (Science 318, 980,2007) reported a nuclear magnetic resonance diagnostic for neural progenitor cells. Characteristics of MRS experiments are known to be problematic for SVD-based methods. Absent detection using alternate methods of spectrum analysis or controls to quantify the false discovery rate, little significance can be attached to their result.

Promoter Library Designed For Fine-Tuned Gene Expression In Pichia Pastoris, Franz S. Hartner, Claudia Ruth, David Langenegger, Sabrina N. Johnson, Petr Hyka, Geoff P. Lin-Cereghino, Joan Lin-Cereghino, Karin Kovar, James Cregg, Anton Glieder

College of the Pacific Faculty Articles

Although frequently used as protein production host, there is only a limited set of promoters available to drive the expression of recombinant proteins in Pichia pastoris. Fine-tuning of gene expression is often needed to maximize product yield and quality. However, for efficient knowledge-based engineering, a better understanding of promoter function is indispensable. Consequently, we created a promoter library by deletion and duplication of putative transcription factor-binding sites within the AOX1 promoter (P_AOX1) sequence. This first library initially spanned an activity range between ∼6% and >160% of the wild-type promoter activity. After characterization of the promoter library employing …

Computational Design Of Orthogonal Ribosomes, Lon Chubiz, Christopher Rao

Biology Department Faculty Works

Orthogonal ribosomes (o-ribosomes), also known as specialized ribosomes, are able to selectively translate mRNA not recognized by host ribosomes. As a result, they are powerful tools for investigating translational regulation and probing ribosome structure. To date, efforts directed towards engineering o-ribosomes have involved random mutagenesisbased approaches. As an alternative, we present here a computational method for rationally designing o-ribosomes in bacteria. Working under the assumption that base-pair interactions between the 16S rRNA and mRNA serve as the primary mode for ribosome binding and translational initiation, the algorithm enumerates all possible extended recognition sequences for 16S rRNA and then chooses those …

Aminoacyl-Trna Synthetase Complexes: Molecular Multitasking Revealed, Corinne D. Hausmann, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The accurate synthesis of proteins, dictated by the corresponding nucleotide sequence encoded in mRNA, is essential for cell growth and survival. Central to this process are the aminoacyl-tRNA synthetases (aaRSs), which provide amino acid substrates for the growing polypeptide chain in the form of aminoacyl-tRNAs. The aaRSs are essential for coupling the correct amino acid and tRNA molecules, but are also known to associate in higher order complexes with proteins involved in processes beyond translation. Multiprotein complexes containing aaRSs are found in all three domains of life playing roles in splicing, apoptosis, viral assembly, and regulation of transcription and translation. …

Evolution Of Metal(Loid) Binding Sites In Transcriptional Regulators, Efrén Ordóñez, Saravanamuthu Thiyagarajan, Jeremy D. Cook, Timothy L. Stemmler, José A. Gil., Luís M. Mateos, Barry P. Rosen

Biochemistry and Molecular Biology Faculty Publications

Expression of the genes for resistance to heavy metals and metalloids is transcriptionally regulated by the toxic ions themselves. Members of the ArsR/SmtB family of small metalloregulatory proteins respond to transition metals, heavy metals and metalloids, including As(III), Sb(III), Cd(II), Pb(II), Zn(II), Co(II) and Ni(II). These homodimeric repressors bind to DNA in absence of inducing metal(loid) ion and dissociate from the DNA when inducer is bound. The regulatory sites are often three- or four-coordinate metal binding sites composed of cysteine thiolates. Surprisingly, in two different As(III)-responsive regulators, the metalloid binding sites were in different locations in the repressor, and the …

Structural And Functional Mapping Of The Archaeal Multi-Aminoacyl-Trna Synthetase Complex, Corinne D. Hausmann, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Methanothermobacter thermautotrophicus contains a multi-aminoacyl-tRNA synthetase complex (MSC) of LysRS, LeuRS and ProRS. Elongation factor (EF) 1A also associates to the MSC, with LeuRS possibly acting as a core protein. Analysis of the MSC revealed that LysRS and ProRS specifically interact with the idiosyncratic N- and C- termini of LeuRS, respectively. EF-1A instead interacts with the inserted CP1 proofreading domain, consistent with models for post-transfer editing by class I synthetases such as LeuRS. Together with previous genetic data, these findings show that LeuRS plays a central role in mediating interactions within the archaeal MSC by acting as a core scaffolding …

A Cytosolic Iron Chaperone That Delivers Iron To Ferritin, Haifeng Shi, Krisztina Z. Bencze, Timothy L. Stemmler, Caroline C. Philpott

Biochemistry and Molecular Biology Faculty Publications

Ferritins are the main iron storage proteins found in animals, plants and bacteria. The capacity to store iron in ferritin is essential for life in mammals, but the mechanism by which cytosolic iron is delivered to ferritin is unknown. Human ferritins expressed in yeast contain little iron. The human Poly r(C)-Binding Protein 1 (PCBP1) increased the amount of iron loaded into ferritin when expressed in yeast. PCBP1 bound to ferritin in vivo, and bound iron and facilitated iron loading into ferritin in vitro. Depletion of PCBP1 in human cells inhibited ferritin iron loading and increased cytosolic iron pools. Thus, PCBP1 …

Atf4 Is An Oxidative Stress–Inducible, Prodeath Transcription Factor In Neurons In Vitro And In Vivo, Philipp Lange, Juan Chavez, John T. Pinto, Giovanni Coppola, Chiao-Wang Sun, Tim Townes, Rajiv Ratan

NYMC Faculty Publications

Oxidative stress is pathogenic in neurological diseases, including stroke. The identity of oxidative stress-inducible transcription factors and their role in propagating the death cascade are not well known. In an in vitro model of oxidative stress, the expression of the bZip transcription factor activating transcription factor 4 (ATF4) was induced by glutathione depletion and localized to the promoter of a putative death gene in neurons. Germline deletion of ATF4 resulted in a profound reduction in oxidative stress-induced gene expression and resistance to oxidative death. In neurons, ATF4 modulates an early, upstream event in the death pathway, as resistance to oxidative …

Collagen 11a1 Is Indirectly Activated By Lymphocyte Enhancer-Binding Factor 1 (Lef1) And Negatively Regulates Osteoblast Maturation, Rachel A. Kahler, Sorcha M.C. Yingst, Luke H. Hoeppner, Eric D. Jensen, David Krawczak, Julia T. Oxford, Jennifer J. Westendorf

Biomolecular Research Center Publications and Presentations

Alpha 1 (XI) collagen (Col11a1) is essential for normal skeletal development. Mutations in Col11a1 cause Marshall and Stickler syndromes, characterized by craniofacial abnormalities, nearsightedness and hearing abnormalities. Despite its link to human diseases, few studies have characterized the factors that control Col11a1 transcription. We previously identified Col11a1 as a differentially expressed gene in Lef1-suppressed MC3T3 preosteoblasts. Here we report that Lef1 activates the Col11a1 promoter. This activation is dependent upon the DNA binding domain of Lef1, but does not require the ß-catenin interaction domain, suggesting that it is not responsive to Wnt signals. Targeted deletion of Col11a1 with an antisense …

Gene Alterations By Peroxisome Proliferator-Activated Receptor Gamma Agonists In Human Colorectal Cancer Cells, Maria Cekanova, X Li, J Yuan, K B. Kim, Seung J. Baek

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear transcription factor that controls the genes involved in metabolism and carcinogenesis. In the present study, we examined the alteration of gene expression in HCT-116 human colorectal cancer cells by PPARgamma agonists: MCC-555 (5 microM), rosiglitazone (5 microM), and 15-deoxy-Delta12,14-prostaglandin J2 (1 microM). The long-oligo microarray data revealed a list of target genes commonly induced (307 genes) and repressed (32 genes) by tested PPARgamma agonists. These genes were analyzed by Onto-Express software and KEGG pathway analysis and revealed that PPARgamma agonists are involved in cell proliferation, focal adhesion, and several signaling pathways. …

Treg Depletion Inhibits Efficacy Of Cancer Immunotherapy: Implications For Clinical Trials., James Curtin, Marianela Candolfi, Tamer Fakhouri, Chunyan Liu, Anderson Alden, Matthew Edwards, Pedro Lowenstein, Maria Castro

Articles

BACKGROUND: Regulatory T lymphocytes (Treg) infiltrate human glioblastoma (GBM); are involved in tumor progression and correlate with tumor grade. Transient elimination of Tregs using CD25 depleting antibodies (PC61) has been found to mediate GBM regression in preclinical models of brain tumors. Clinical trials that combine Treg depletion with tumor vaccination are underway to determine whether transient Treg depletion can enhance anti-tumor immune responses and improve long term survival in cancer patients. FINDINGS: Using a syngeneic intracrabial glioblastoma (GBM) mouse model we show that systemic depletion of Tregs 15 days after tumor implantation using PC61 resulted in a decrease in Tregs …

Turning The Gene Tap Off; Implications Of Regulating Gene Expression For Cancer Therapeutics, James Curtin, Marianela Candolfi, Weidong Xiong, Pedro Lowenstein, Maria Castro

Articles

Cancer poses a tremendous therapeutic challenge worldwide, highlighting the critical need for developing novel therapeutics. A promising cancer treatment modality is gene therapy, which is a form of molecular medicine designed to introduce into target cells genetic material with therapeutic intent. Anticancer gene therapy strategies currently used in preclinical models, and in some cases in the clinic, include proapoptotic genes, oncolytic/replicative vectors, conditional cytotoxic approaches, inhibition of angiogenesis, inhibition of growth factor signaling, inactivation of oncogenes, inhibition of tumor invasion and stimulation of the immune system. The translation of these novel therapeutic modalities from the preclinical setting to the clinic …

Monitoring Lys-TrnaLys Phosphatidylglycerol Transferase Activity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In some bacteria Lys-tRNA^Lys is used both in translation and for the specific addition of Lys to phosphatidylglycerol in the cytoplasmic membrane. This reaction is catalyzed by the membrane protein MprF, and the lysyl-phosphatidylglycerol formed contributes to the resistance of these bacteria to various cationic antibacterial molecules. Obtaining proteins and reconstituting an in vitro system mimicking membrane conditions is a major challenge to studying the function of membrane proteins, especially when labile substrates such as Lys-tRNA^Lys are required. Here we report methods to obtain a stable enriched membrane fraction containing MprF, and the techniques necessary to quantitatively monitor …

Offsprings Of Hypertensive Parents Have Higher Blood Pressure And Bmi, Syed Faraz Kazim, Muhammad Bilal Salman, Akbar Jaleel Zubairi, Aisha Afzal, Usman Ahmad, Philippe M Frossard

Department of Biological & Biomedical Sciences

No abstract provided.

A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Pattee Pond (2008, 1992)

The Colby Environmental Assessment Team (CEAT) investigated the impact of land use patterns on the water quality of Pattee Pond in Winslow, Maine, during the summer and fall of 2008. Physical, chemical, and biological characteristics of water quality were analyzed to evaluate the current health of the lake. Data collected were compared with previous studies conducted by the Maine Department of Environmental Protection (DEP) and CEAT to examine changes in water quality and land use over time. Trends in Pattee Pond water quality suggest an improvement since the 1970s. However, the lake is still experiencing algal blooms resulting from phosphorus …

Bmp Signaling Goes Posttranscriptional In A Microrna Sort Of Way, Catherine A. Reinke, Richard W. Carthew

Faculty Publications

Aberrant microRNA (miRNA) expression correlates with human diseases such as cardiac disorders and cancer. Treatment of such disorders using miRNA-targeted therapeutics requires a thorough understanding of miRNA regulation in vivo. A recent paper in Nature by Davis et al. expands our understanding of miRNA biogenesis and maturation, elucidating a mechanism by which extracellular signaling directs cell differentiation via posttranscriptional regulation of miRNA expression.

Distinct Phospho-Forms Of Cortactin Differentially Regulate Actin Polymerization And Focal Adhesions, Anne E. Kruchten, Eugene W. Krueger, Yu Wang, Mark A. Mcniven

Faculty Publications

Cortactin is an actin-binding protein that is overexpressed in many cancers and is a substrate for both tyrosine and serine/threonine kinases. Tyrosine phosphorylation of cortactin has been observed to increase cell motility and invasion in vivo, although it has been reported to have both positive and negative effects on actin polymerization in vitro. In contrast, serine phosphorylation of cortactin has been shown to stimulate actin assembly in vitro. Currently, the effects of cortactin serine phosphorylation on cell migration are unclear, and furthermore, how the distinct phospho-forms of cortactin may differentially contribute to cell migration has not been directly compared. Therefore, …

The Caenorhabditis Globin Gene Family Reveals Extensive Nematode-Specific Radiation And Diversification, David Hoogewijs, Sasha De Henau, Sylvia Dewilde, Luc Moens, Marjolein Couvreur, Gaetan Borgonie, Serge N. Vinogradov, Scott W. Roy, Jacques R. Vanfleteren

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Globin isoforms with variant properties and functions have been found in the pseudocoel, body wall and cuticle of various nematode species and even in the eyespots of the insect-parasite Mermis nigrescens. In fact, much higher levels of complexity exist, as shown by recent whole genome analysis studies. In silico analysis of the genome of Caenorhabditis elegans revealed an unexpectedly high number of globin genes featuring a remarkable diversity in gene structure, amino acid sequence and expression profiles.

Results

In the present study we have analyzed whole genomic data from C. briggsae, C. remanei, Pristionchus pacificus and Brugia malayi …

A Phylogenomic Profile Of Hemerythrins, The Nonheme Diiron Binding Respiratory Proteins, Xavier Bailly, Stefano Vanin, Christine Chabasse, Kenji Mizuguchi, Serge N. Vinogradov

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Hemerythrins, are the non-heme, diiron binding respiratory proteins of brachiopods, priapulids and sipunculans; they are also found in annelids and bacteria, where their functions have not been fully elucidated.

Results

A search for putative Hrs in the genomes of 43 archaea, 444 bacteria and 135 eukaryotes, revealed their presence in 3 archaea, 118 bacteria, several fungi, one apicomplexan, a heterolobosan, a cnidarian and several annelids. About a fourth of the Hr sequences were identified as N- or C-terminal domains of chimeric, chemotactic gene regulators. The function of the remaining single domain bacterial Hrs remains to be determined. In …

Association Of Copper To Riboflavin Binding Protein; Characterization By Epr And Xas, Shelia R. Smith, Krisztina Z. Bencze, Kristen Wasiukanis, Timothy L. Stemmler, Marilee Benore-Parsons

Biochemistry and Molecular Biology Faculty Publications

The association of copper to Riboflavin Binding Protein (RBP) from egg white has been studied by electron paramagnetic resonance (EPR) and X-ray absorption (XAS) spectroscopies. The type II site contains a mix of copper I and II in an oxygen rich environment.

Il-21 Limits Peripheral Lymphocyte Numbers Through T Cell Homeostatic Mechanisms., Shrimati Datta, Nora E. Sarvetnick

Journal Articles: Regenerative Medicine

BACKGROUND: IL-21, a member of the common gamma-chain utilizing family of cytokines, participates in immune and inflammatory processes. In addition, the cytokine has been linked to autoimmunity in humans and rodents.

METHODOLOGY/PRINCIPAL FINDINGS: To investigate the mechanism whereby IL-21 affects the immune system, we investigated its role in T cell homeostasis and autoimmunity in both non-autoimmune C57BL/6 and autoimmune NOD mice. Our data indicate that IL-21R knockout C57BL/6 and NOD mice show increased size of their lymphocyte population and decreased homeostatic proliferation. In addition, our experimental results demonstrate that IL-21 inhibits T cell survival. These data suggest that IL-21 acts …

7Β-Hydroxy­Artemisinin, Paulo B. Carvalho, Bo Liu, Yunshan Wu, John S. Williamson, Mitchell A. Avery

Office for Research Publications and Presentations

Crystals of the title compound [systematic name: (3R,6R,7S,8aR,9R,12aR)-7-hydr­oxy-3,6,9-trimethyl­octa­hydro-3,12-ep­oxy[1,2]dioxepino[4,3-i]isochromen-10(3H)-one], C₁₅H₂₂O₆, were obtained from microbial transformation of artemisinin by a culture of Cunninghamella elegans. The stereochemistry of the compound is consistent with the spectroscopic findings in previously published works. A weak O—H⋯O hydrogen bond occurs in the crystal structure, together with intermolecular C—H⋯O hydrogen bonds.

Identification Of Lactic Acid Bacteria In Michigan Cherry Wines, Emily Henk, Margaret Dietrich, Terri Weese

Student Summer Scholars Manuscripts

Many factors contribute to the final flavor of wine. One factor is malolactic fermentation, during which lactic acid bacteria (LAB) transform the harsh tasting malic acid into a more drinkable lactic acid in grape wine. The role of LAB in the production of cherry wine is completely unknown. The goal of this study is to identify the species of LAB in cherry wine and compare them to those found in grape wines. Bacteria from cherry wine were grown on general media plates and plates fortified with malic acid, which may provide optimal growing conditions for the LAB. To identify the …

Regulated Expression Of Adenoviral Vectors-Based Gene Therapies: Therapeutic Expression Of Toxins And Immune-Modulators, James Curtin, Marianela Candolfi, Mariana Puntel, Weidong Xiong, Akm Ghulam Muhammad, Kurt Kroeger, Sonali Mondkar, Chunyan Liu, Niyati Bondale, Pedro Lowenstein, Maria Castro

Articles

Regulatable promoter systems allow gene expression to be tightly controlled in vivo. This is highly desirable for the development of safe, efficacious adenoviral vectors that can be used to treat human diseases in the clinic. Ideally, regulatable cassettes should have minimal gene expression in the "OFF" state, and expression should quickly reach therapeutic levels in the "ON" state. In addition, the components of regulatable cassettes should be non-toxic at physiological concentrations and should not be immunogenic, especially when treating chronic illness that requires long-lasting gene expression. In this chapter, we will describe in detail protocols to develop and validate first …