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Articles 6481 - 6510 of 6985

Full-Text Articles in Biochemistry

Altering The Rna Binding Specificity Of A Translational Repressor, F Lim, Marc Spingola, D Peabody Mar 1994

Altering The Rna Binding Specificity Of A Translational Repressor, F Lim, Marc Spingola, D Peabody

Biology Department Faculty Works

The coat proteins of RNA phages MS2 and GA are specific RNA-binding proteins which function to encapsidate viral RNA and to translationally repress synthesis of the viral replicase. The two proteins have highly homologous amino acid sequences, yet they show different RNA binding specificities, recognizing RNA stem-loop structures which differ primarily in the nucleotide sequences of their loops. We sought to convert MS2 coat protein to the RNA binding specificity of GA through the introduction of GA-like amino acid substitutions into the MS2 coat protein RNA-binding site. The effects of the mutations were determined by measuring the affinity of the …

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Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority Feb 1994

Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority

Publications (WR)

The purpose of Task 010A15M of the Southern Nevada Water Authority (SNWA) Treatment and Transmission Facility (TTF) contract is to conduct a study of existing information concerning water quality within Lake Mead and identify additional water quality studies that are needed to supplement existing data. The objective of this task is not to discuss treatability of the raw water source; this is addressed by Task 010A18M, "Define Water Treatment Requirements." In addition, a narrative on the effect of pending Safe Drinking Water Act amendments and a determination of treated water quality goals is included in Task 010A16M, "Review Safe Drinking …

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Separate Metabolic Pathways Leading To Dna Fragmentation And Apoptotic Nuclear Chromatin Condensation, D. Sun, Shibo Jiang, Li-Mou Zheng, David M. Ojcius, John Ding-E. Young Feb 1994

Separate Metabolic Pathways Leading To Dna Fragmentation And Apoptotic Nuclear Chromatin Condensation, D. Sun, Shibo Jiang, Li-Mou Zheng, David M. Ojcius, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Apoptosis is the predominant form of cell death observed in a variety of physiological and pathological conditions such as cancer involution, insect metamorphosis, the development of the immune and nervous systems, and embryogenesis. The typical nuclear changes taking place in apoptotic cells include extensive condensation of chromatin and internucleosomal DNA fragmentation into units of 200 base pairs. However, the mechanisms responsible for both chromatin condensation and DNA fragmentation have yet to be elucidated. In this study, micrococcal nuclease and the divalent cations, Ca2+ and Mg2+, were applied to isolated nuclei in an attempt to reconstitute in vitro the digestion of …

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Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson Jan 1994

Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson

Chemistry Faculty Publications

Haemophilus ducreyi, a cause of genital ulcer disease in developing countries, appears to facilitate the heterosexual transmission of the human immunodeficiency virus in Africa. Despite an increase in studies of this gram-negative human pathogen, little is known about the pathogenesis of chancroid. Our studies have shown that the lipooligosaccharides (LOS) of H. ducreyi may play an important role in ulcer formation. Monoclonal antibody and mass spectrometric analyses identified a terminal trisaccharide present on H. ducreyi LOS that is immunochemically similar to human paragloboside. This epitope is present on the LOS of Neisseria gonorrhoeae, and it may be the site of …

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Evidence Of Steric Factors In The Fungitoxic Mechanism Of 8-Quinolinol And Its 2-, 3-, 4-, 5-, 6- And 7-Chloro And Bromo Analogues / Herman Gershon, Donald D. Clarke, And Muriel Gershon Department Of Chemistry, Fordham University, Bronx, Ny 10458, Usa New York Botanical Garden, Bronx, Ny 10458, Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon Jan 1994

Evidence Of Steric Factors In The Fungitoxic Mechanism Of 8-Quinolinol And Its 2-, 3-, 4-, 5-, 6- And 7-Chloro And Bromo Analogues / Herman Gershon, Donald D. Clarke, And Muriel Gershon Department Of Chemistry, Fordham University, Bronx, Ny 10458, Usa New York Botanical Garden, Bronx, Ny 10458, Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon

Chemistry Faculty Publications

A study was made of the fungitoxicity of 2-, 3-, 4-, 5-, 6- and 7-chloro and bromo- 8-quinolinols against Aspergillus niger, A. oryzae, Myrothecium verrucaria, Trichoderma viride and Trichophyton mentagrophytes in Sabouraud dextrose broth and in Yeast Nitrogen Base supplemented with 1% D-glucose and 0.088% L-asparagine. Based on the presence or absence of synergism between pairs of substituted 8-quinolinols and reversal or nonreversal of toxicity by L-cysteine or Nacetyl- L-cysteine, the following conclusions were reached: (1) substituents on the quinoline ring change the site(s) of action of the toxicant; (2) the sites of action of the 5-, 6-, and 7-chloro-8-quinolinols …

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Preparation And Fungitoxicity Of 3,6-Dichloro- And 3,6-Dibromo-8-Quinolinols / H. Gershon, D. D. Clarke, And M. Gershon Department Of Chemistry, Fordham University, Bronx, Ny 10458, Usa New York Botanical Garden, Bronx, Ny 10458, Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon Jan 1994

Preparation And Fungitoxicity Of 3,6-Dichloro- And 3,6-Dibromo-8-Quinolinols / H. Gershon, D. D. Clarke, And M. Gershon Department Of Chemistry, Fordham University, Bronx, Ny 10458, Usa New York Botanical Garden, Bronx, Ny 10458, Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon

Chemistry Faculty Publications

3,6-Dichloro- and 3,6-dibromo-8-quinolinols were prepared by direct halogenation of 8-nitroquinoline by N-halosuccinimide in acetic acid or by halogenation of the corresponding 6-halo-8-nitroquinoline prepared via a Skraup reaction. The nitro group was reduced to amino and the amine was hydrolyzed to the phenol in 70% sulfuric acid at 220 °C. The fungitoxicity of 3,6-dichloro- and 3,6-dibromo-8-quinolinols, as well as intermediates in their preparation, against Aspergillus niger, Aspergillus oryzae, Myrothecium verrucaria, Trichoderma viride, and Mucor cirinelloides was determined. 3,6-dichloro-8-quinolinol is the most fungitoxic analogue of this class of compounds observed to date

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Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle Jan 1994

Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle

Faculty Publications, Biological Sciences

No abstract provided.

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The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton Jan 1994

The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton

Faculty Publications, Biological Sciences

The conversion of mammalian prelamin A to mature lamin A proceeds through the removal of 18 amino acids from the carboxyl terminus. The initial step in this processing is the isoprenylation of a CAAX box cysteine. This proteolytic event is distinctive for prelamin A among the known prenylated mammalian proteins. Since the carboxyl terminus of prelamin A is removed during maturation, it is not obvious that this protein would undergo the two reactions subsequent to prenylation observed in other CAAX box proteins-the endoproteolytic removal of the carboxyl-terminal 3 amino acids and the subsequent methylation of the now carboxyl-terminal cysteine. To …

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Transformation Related Defects In Vacuolar Acidification And Mannose 6-Phosphate Receptor Function: Effects On Lysosomal Targeting, Valerie Pracht Jan 1994

Transformation Related Defects In Vacuolar Acidification And Mannose 6-Phosphate Receptor Function: Effects On Lysosomal Targeting, Valerie Pracht

Dissertations

No abstract provided.

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Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan Jan 1994

Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan

Journal of the Arkansas Academy of Science

No abstract provided.

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Biogeochemical Control Of Phosphorus Cycling And Primary Production In Lake Michigan, R. S. Walsh, Gregory A. Cutter, W. M. Dunstan, J. Radford-Knoery, J. T. Elder Jan 1994

Biogeochemical Control Of Phosphorus Cycling And Primary Production In Lake Michigan, R. S. Walsh, Gregory A. Cutter, W. M. Dunstan, J. Radford-Knoery, J. T. Elder

OES Faculty Publications

A 3-yr study in Lake Michigan has shown a 27 mmol P m-2 increase in the mass of total P (TP) in the water during spring when the lake is mixed from surface to sediment. This value is an order of magnitude greater than the annual P input from external sources. TP changed in concert with increases in chlorophyll a and organic N and decreases in nitrate and soluble Si. The concentration of soluble reactive PO4-3 (SRP) remained relatively constant throughout the study. We hypothesize that the SRP concentration is maintained by a chemical equilibrium with calcium-phosphate …

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The Endocytosis Of Iodinated Protein Substrates In Cultured Human Skin Fibroblasts, Daniel P. Wilcockson Jan 1994

The Endocytosis Of Iodinated Protein Substrates In Cultured Human Skin Fibroblasts, Daniel P. Wilcockson

Master's Theses

No abstract provided.

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Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac Jan 1994

Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac

Journal of the Arkansas Academy of Science

Initial studies involved the thermal decomposition profile of five polysulfide complexes in air up to 550 °C. Since our first report to the Academy in 1990, we have obtained the capability to run samples up to 1500°C under various gases. Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA)of a series of transition metal polysulfide complexes are presented. Compounds analyzed included Cp2TiS5 ,MoS9 2",MoOS8 2", Zn(S x ) 2", Cd(S x ) 2-, Fe2S122 - and NiS82.

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Subunit Interactions Of Recombinant Hiv-1 Reverse Transcriptase With Mutations At L289, Jacquelyn R. Smith Jan 1994

Subunit Interactions Of Recombinant Hiv-1 Reverse Transcriptase With Mutations At L289, Jacquelyn R. Smith

Theses and Dissertations in Biomedical Sciences

Reverse transcriptase (RT) is a dimeric enzyme required for replication of the human immunodeficiency virus (HIV). If the subunits of the RT dimer are dissociated, the enzyme is no longer active; therefore, identification of subunit binding sites could lead to potential targets for antiviral therapy. In order to identify where subunit binding of RT occurs, mutations were made at leucine (L) 289, a residue believed to be involved in dimerization through hydrophobic interactions with other leucines. L289 is the central leucine of a leucine repeat sequence which resembles a leucine zipper protein-DNA binding motif. Two mutations, leucine to arginine (L289R) …

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Characteristics Of Modified Leghemoglobins Lsolated From Soybean (Glycine Max Merr.) Root Nodules, Hyung-Kyun Jun, Gautam Sarath, Jose F. Moran, Manuel Becana, Robert V. Klucas, Fred W. Wagner Jan 1994

Characteristics Of Modified Leghemoglobins Lsolated From Soybean (Glycine Max Merr.) Root Nodules, Hyung-Kyun Jun, Gautam Sarath, Jose F. Moran, Manuel Becana, Robert V. Klucas, Fred W. Wagner

Department of Biochemistry: Faculty Publications

Hemoprotein derivatives of an abundant soybean (Glycine max Merr.) root nodule leghemoglobin, Lba, were studied for their modified spectral characteristics and physical properties. Three modified hemoprotein derivatives of Lba (Lbam1, Lbam2, and Lbam3) were purified by preparative isoelectric focusing. The ferric forms of these pigments were green and exhibited anomalous spedra in the visible region as compared to the Lba3+ forms. These modified pigments showed a hypochromic shift of 10 nm for the charge transfer absorption maximum; however, differences were not apparent in the Sdret region. Upon binding with nicotinate, the α …

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Sequence Of A Psac Gene From The Cyanobacterium Synechococcus Sp. Pcc 6301, Patricia L. Herman, Kartika Adiwilaga, John H. Golbeck, Donald P. Weeks Jan 1994

Sequence Of A Psac Gene From The Cyanobacterium Synechococcus Sp. Pcc 6301, Patricia L. Herman, Kartika Adiwilaga, John H. Golbeck, Donald P. Weeks

Department of Biochemistry: Faculty Publications

The psaC gene encodes PsaC, the apoprotein for the terminal iron-sulfur clusters, FA and FB, in the PSI reaction center of cyanobacteria, algae, and higher plants. PsaC functions as a membrane-bound oxidoreductase, accepting electrons from the Fx iron-sulfur cluster located on the PsaA/PsaB heterodimer and donating them to the soluble electron transfer proteins Fd and flavodoxin (reviewed in Bryant, 1992). The objective of our work is to clarify the role of PsaC in linear and cyclic electron transfer. The experimental organism is Syneckococcus sp. PCC 6301, a unicellular, freshwater cyanobacterium that is used extensively for physiological, …

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Exopeptidase Catalyzed Site-Specific Bonding Of Supports, Labels And Bioactive Agents To Proteins, Fred W. Wagner, Thomas R. Coolidge, Dwane E. Wylie, Sheldon M. Schuster, William Lewis, Jay Stout Jan 1994

Exopeptidase Catalyzed Site-Specific Bonding Of Supports, Labels And Bioactive Agents To Proteins, Fred W. Wagner, Thomas R. Coolidge, Dwane E. Wylie, Sheldon M. Schuster, William Lewis, Jay Stout

Department of Biochemistry: Faculty Publications

The invention provides a means for attaching a label, support or bioactive agent to a protein with an exopeptidase at a site that is remote from the active site of the protein. More specifically the invention is directed to a method for the attachment of an amino acid, amine and alcohol nucleophile to the carboxyl terminus of a protein. In one embodiment, a labeled nucleophile is attached to a protein such as an antibody. In other embodiments, the invention is directed to a method for the attachment of a protein to an immobilization support and to a method for the …

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Binding Of Matrix Attachment Regions To Lamin Polymers Involves Single-Stranded Regions And The Minor Groove., M. E. Eva Ludérus, Jan L. Den Blaauwen, Oncko J. De Smit, Duane A. Compton, Roel Van Driel Jan 1994

Binding Of Matrix Attachment Regions To Lamin Polymers Involves Single-Stranded Regions And The Minor Groove., M. E. Eva Ludérus, Jan L. Den Blaauwen, Oncko J. De Smit, Duane A. Compton, Roel Van Driel

Dartmouth Scholarship

Chromatin in eukaryotic nuclei is thought to be partitioned into functional loop domains that are generated by the binding of defined DNA sequences, named MARs (matrix attachment regions), to the nuclear matrix. We have previously identified B-type lamins as MAR-binding matrix components (M. E. E. Ludérus, A. de Graaf, E. Mattia, J. L. den Blaauwen, M. A. Grande, L. de Jong, and R. van Driel, Cell 70:949-959, 1992). Here we show that A-type lamins and the structurally related proteins desmin and NuMA also specifically bind MARs in vitro. We studied the interaction between MARs and lamin polymers in molecular detail …

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Regulatory Analysis Of Vimentin Expression In Metastatic Versus Nonmetastatic Breast Cancer Cell Lines, Danielle N. Bird Jan 1994

Regulatory Analysis Of Vimentin Expression In Metastatic Versus Nonmetastatic Breast Cancer Cell Lines, Danielle N. Bird

Theses and Dissertations

The intermediate filament gene family, composed of six classes, shows both tissue and development-specific expression. Vimentin is a unique member of the intermediate filament protein family: although it is expressed in cells of mesenchymal origin, vimentin may also be expressed with other intermediate filament proteins during early stages of development. In some cases, as differentiation continues, vimentin is normally down-regulated whereas other intermediate filament proteins, like desmin, glial fibrillary acidic protein, or neurofilaments are turned on in muscle, glial cells, or neurons, respectively. In some metastatic cancers, including breast and prostate cancers, vimentin is aberrantly expressed, despite the embryonic origin …

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Expression, Purification And Characterization Of Hepatitis C Virus Core Protein From E.Coli Using A Chemically Synthesized Gene (1), And Cloning, Expression, Purification And Characterization Of The Major Core Protein (P26) From Equine Infectious Anaemia Virus, Ashley James Birkett Jan 1994

Expression, Purification And Characterization Of Hepatitis C Virus Core Protein From E.Coli Using A Chemically Synthesized Gene (1), And Cloning, Expression, Purification And Characterization Of The Major Core Protein (P26) From Equine Infectious Anaemia Virus, Ashley James Birkett

Theses and Dissertations

The hepatitis c virus (HCV) core gene has been chemically synthesized and used to direct the expression of core protein in Escherichia coli (E.coli). When cloned downstream of the inducible T7 promotor the core gene directed the expression of a soluble protein with a molecular weight of 22 kDa. Under native conditions the protein behaved in a manner consistent with the formation of a multimeric structure, which may represent assembled core particles. Further, when examined by electron microscopy a heterogeneous mixture of nucleocapsid-like particles were visible. Core protein was specifically recognized by antibodies present in HCV infected serum, suggesting that …

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Cloning, Expression, Purification And Characterization Of Domain B Of Wheat Germ Agglutinin, Ann C. Rice Jan 1994

Cloning, Expression, Purification And Characterization Of Domain B Of Wheat Germ Agglutinin, Ann C. Rice

Theses and Dissertations

Wheat germ agglutinin (WGA) belongs to a family of dimeric chitin binding lectins specific for N-acetyl-D-glucosamine (GlcNAc) and N-acetyl-D-neuraminic acid (NeuNAc). The polypeptide chain consists of a tandem repeat of four conserved 4.3 kDa domains (A, B, C, D) stabilized by four disulfide bonds. Saccharide binding occurs in the dimer interface where domains of different subunits are in contact (A with D, B with C). An aromatic amino acid rich pocket on one domain (sufficient for saccharide binding) and a polar region on the contacting domain constitute a complete binding site. Saccharide binding affinities may differ among the four unique …

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Severe Bone Marrow Suppression In A Patient With Rheumatoid Arthritis On Methotrexate, M P. Iqbal, A A. Ali, A A. Alvi Dec 1993

Severe Bone Marrow Suppression In A Patient With Rheumatoid Arthritis On Methotrexate, M P. Iqbal, A A. Ali, A A. Alvi

Department of Biological & Biomedical Sciences

No abstract provided.

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Tyrosyl Protein Phosphorylation In Human Bone Cells : Its Potential Role In Mediating Fluoride Induced Osteoblast Proliferation, Alan Blair Thomas Dec 1993

Tyrosyl Protein Phosphorylation In Human Bone Cells : Its Potential Role In Mediating Fluoride Induced Osteoblast Proliferation, Alan Blair Thomas

Loma Linda University Electronic Theses, Dissertations & Projects

This dissertation was designed to test the hypothesis that fluoride-stimulated osteoblast proliferation is mediated by specific inhibition of a phosphotyrosyl protein phosphatase, resulting in increased steady state levels of tyrosyl phosphorylation of key cellular proteins. Cellular levels of tyrosyl phosphorylation were determined by an immunoblot detection assay in which cellular proteins were separated by SDS-PAGE, transblotted to nitrocellulose membranes and the phosphotyrosyl proteins were identified by anti-phosphotyrosine monoclonal antibodies. The relative amount of tyrosyl phosphorylation was quantitated by laser densitometric analysis of the autoradiograms. This method showed that fluoride induced dose- and time-dependent changes in the level of tyrosyl phosphorylation …

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A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane Dec 1993

A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane

Electronic Theses and Dissertations

Extraction of the lipids of Legionella pneumophila yields phases unlike those produced from other Gram-negative bacteria. A viscous interface forms between the aqueous (wash) and organic phases. More than half of the hydroxylated fatty acids were found distributed between the aqueous phase and the interfacial material, fractions in which such constituents have not been reported in other Gram-negative species. It was further observed that after the material from the aqueous/interfacial phase was dissolved in methanol or chloroform/methanol (2:1 (V/V)), the addition of acetone would create a white, flocculent precipitate. Analyses showed that the supernatant contained fatty acids that were nonhydroxylated …

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A Molecular Basis For Erythromycin Sensitivity And Resistance In Escherichia Coli, Harold S. Chittum Dec 1993

A Molecular Basis For Erythromycin Sensitivity And Resistance In Escherichia Coli, Harold S. Chittum

Electronic Theses and Dissertations

The effect of erythromycin on the 50S ribosomal subunit during cell growth has been extensively investigated. Sucrose density gradient analysis of ribosomes formed in the presence and absence of the drug revealed a 50S specific assembly defect is partially responsible for erythromycin's inhibitory effects on wild type cells. Examination of two erythromycin-resistant mutants of E. coli (N281 and N282) revealed that mutant N281 (L22 mutant) but not N282 (L4 mutant) was assembly defective in the presence of the drug, although only at much higher drug concentrations (300 ug/ml vs. 75 ug/ml for wild type cells). The altered genes from each …

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The 2′-Phosphate Of Nadp Is Critical For Optimum Productive Binding To 6-Phosphogluconate Dehydrogenase From Candida Utilis, Anthony J. Berdis, Paul F. Cook Sep 1993

The 2′-Phosphate Of Nadp Is Critical For Optimum Productive Binding To 6-Phosphogluconate Dehydrogenase From Candida Utilis, Anthony J. Berdis, Paul F. Cook

Chemistry Faculty Publications

Initial velocity studies obtained with alternative dinucleotide substrates for the 6-phosphogluconate dehydrogenase reaction suggest that the 2′-phosphate is critical for the optimum productive binding of the dinucleotide substrate. Initial velocity patterns obtained by varying 6-phosphogluconate at different fixed levels of NAD are nearly parallel with apparent competitive substrate inhibition by 6-phosphogluconate at pH 7 and below but intersect to the left of the ordinate at pH 8 and above. Dead-end inhibition studies indicate that the mechanism is random at all pH values. Data are interpreted in terms of a random mechanism with marked antagonism in the binding of NAD and …

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The Primary Structure Of A Fungal Chitin Deacetylase Reveals The Function For Two Bacterial Gene Products., Dimitris Kafetzopoulos, George Thireos, John N. Vournakis, Vassilis Bouriotis Sep 1993

The Primary Structure Of A Fungal Chitin Deacetylase Reveals The Function For Two Bacterial Gene Products., Dimitris Kafetzopoulos, George Thireos, John N. Vournakis, Vassilis Bouriotis

Dartmouth Scholarship

Chitin deacetylase (EC 3.5.1.41) hydrolyzes the N-acetamido groups of N-acetyl-D-glucosamine residues in chitin. A cDNA to the Mucor rouxii mRNA encoding chitin deacetylase was isolated, characterized, and sequenced. Protein sequence comparisons revealed significant similarities of the fungal chitin deacetylase to rhizobial nodB proteins and to an uncharacterized protein encoded by a Bacillus stearothermophilus open reading frame. These data suggest the functional homology of these evolutionarily distant proteins. NodB is a chitooligosaccharide deacetylase essential for the biosynthesis of the bacterial nodulation signals, termed Nod factors. The observed similarity of chitin deacetylase to the B. stearothermophilus gene product suggests that this gene …

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Sds Non-Acrylamide Polymeric Gel-Filled Capillary Electrophoresis For Molecular Size Separation Of Protein, Devon Andres Aug 1993

Sds Non-Acrylamide Polymeric Gel-Filled Capillary Electrophoresis For Molecular Size Separation Of Protein, Devon Andres

Honors Theses

Sodium dodecyl sulfide (SDS) non-acrylamide gel-filled capillary columns are a new technology being used for analysis and separation of biotechnology-derived proteins. This research was to compare this new technology to the current methods of SDS polyacrylamide gel electrophoresis (SDS-PAGE) and high-performance size-exclusion chromatography (HPSEC). The molecular mass of four different recombinant proteins were determined by two commercialized SDS non-acrylamide gel-filled capillary columns, SDS-PAGE, and HPSEC. The data obtained showed that the SDS non-acrylamide gel-filled capillary columns were compatible with the SDS-PAGE technique for molecular mass determination. HPSEC was shown to be unreliable for molecular weight determination. SDS non-acrylamide gel-filled capillary …

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Aerotaxis In Bacillus Subtilis, Laurence Samuel Wong Aug 1993

Aerotaxis In Bacillus Subtilis, Laurence Samuel Wong

Loma Linda University Electronic Theses, Dissertations & Projects

B. subtilis, like Escherichia coli and Salmonella typhimurium, responded to a step increase in oxygen concentration by swimming smoothly (~ 35 s duration) and to a decrease in oxygen by tumbling. In a spatial gradient of oxygen in liquid media, a band of cells congregated near the air interface. Aerotaxis required a functioning respiratory chain. Adaptation of B. subtilis, E. coli and S. typhimurium to media containing amino acids requires methylation of receptors/methyl-accepting chemotaxis proteins. Adaptation to oxygen and phosphotransferase sugar substrates in B. subtilis was dependent on methylation, unlike similar adaptation in E. coli and S. typhimurium. …

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The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy Jul 1993

The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy

Chemistry & Biochemistry Theses & Dissertations

Grape seed extract is being marketed in France for cardiovascular use and skin care. The active constituents of both these drugs are certain polyphenols called procyanidins. A similar seed extract has now been obtained from Virginia Chardonnay grape seeds. Ten of the major components in this extract have been isolated in their pure form by the semi-preparative HPLC separation on a YMC ODS-AQ (Octadecylsilane-AQ) column. The ODS-Aq column has been shown to have a better resolving capacity compared to the Spherisorb ODS (Octadecylsilane) column previously described in the literature. This has been attributed to the ODSAQ support which has both …

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