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Dissociation From The Oligomeric State Is The Rate-Limiting Step In Fibril Formation By Kappa-Casein, Heath Ecroyd, Tomas Koudelka, David Thorn, Danielle M. Williams, Glyn Devlin, Peter Hoffmann, John A. Carver Jan 2008

Dissociation From The Oligomeric State Is The Rate-Limiting Step In Fibril Formation By Kappa-Casein, Heath Ecroyd, Tomas Koudelka, David Thorn, Danielle M. Williams, Glyn Devlin, Peter Hoffmann, John A. Carver

Faculty of Science - Papers (Archive)

Amyloid fibrils are aggregated and precipitated forms of protein in which the protein exists in highly ordered, long, unbranching threadlike formations that are stable and resistant to degradation by proteases. Fibril formation is an ordered process that typically involves the unfolding of a protein to partially folded states that subsequently interact and aggregate through a nucleation-dependent mechanism. Here we report on studies investigating the molecular basis of the inherent propensity of the milk protein, kappa-casein, to form amyloid fibrils. Using reduced and carboxymethylated kappa-casein ( RCM kappa-CN), we show that fibril formation is accompanied by a characteristic increase in thioflavin …


Instant Insight: Think Outside The Cell, Mark R. Wilson, Justin J. Yerbury Jan 2008

Instant Insight: Think Outside The Cell, Mark R. Wilson, Justin J. Yerbury

Faculty of Science - Papers (Archive)

Proteins perform many different functions critical for life, from building our muscle structure to digesting our food. These large biological molecules each have a unique three-dimensional shape which they require to perform their function. In protein deposition diseases (PDDs), however, a disease-specific protein molecule unfolds from its normal shape and assembles together with like molecules into insoluble rod-shaped fibrils. These protein deposits can be found in the brain, skeletal tissue and various organs; in some cases they may become large enough to disrupt tissue structure and function.


Diastereoselective Ritter Reactions Of Chiral Cyclic N-Acyliminium Ions: Synthesis Of Pyrido- And Pyrrolo [2,3-D] Oxazoles And 4-Hydroxy-5-N-Acylaminopyrrolidines And 5-Hydroxy-6-N-Acylaminopiperidines, Ian R. Morgan, Arife Yazici, Stephen G. Pyne, Brian W. Skelton Jan 2008

Diastereoselective Ritter Reactions Of Chiral Cyclic N-Acyliminium Ions: Synthesis Of Pyrido- And Pyrrolo [2,3-D] Oxazoles And 4-Hydroxy-5-N-Acylaminopyrrolidines And 5-Hydroxy-6-N-Acylaminopiperidines, Ian R. Morgan, Arife Yazici, Stephen G. Pyne, Brian W. Skelton

Faculty of Science - Papers (Archive)

Pyrido- and pyrrolo[2,3-d]oxazoles can be conveniently prepared in high yield from the Ritter reaction of nitriles and in situ generated chiral cyclic N-acyliminium ions. cis-4-Hydroxy-5-acylaminopyrrolidines and cis-5-hydroxy-6-acylaminopiperidines can be readily obtained by acid hydrolysis of these bicyclic heterocyclic compounds, respectively.


On The Electrodeposition Of Titanium In Ionic Liquids, William E. Price, Gordon G. Wallace, Douglas Macfarlane, S Z. El Abedin, A Y. Saad, F Endres, E M. Moustafa, P J. Newman, A Bund, N Borissenko Jan 2008

On The Electrodeposition Of Titanium In Ionic Liquids, William E. Price, Gordon G. Wallace, Douglas Macfarlane, S Z. El Abedin, A Y. Saad, F Endres, E M. Moustafa, P J. Newman, A Bund, N Borissenko

Faculty of Science - Papers (Archive)

The ability to electrodeposit titanium at low temperatures would be an important breakthrough for making corrosion resistant layers on a variety of technically important materials. Ionic liquids have often been considered as suitable solvents for the electrodeposition of titanium. In the present paper we have extensively investigated whether titanium can be electrodeposited from its halides (TiCl4, TiF4, TiI4) in different ionic liquids, namely1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIm]Tf2N), 1-butyl-1-methylpyrrolidinium bis(trifluoromethyl-sulfonyl)amide ([BMP]Tf2N), and trihexyltetradecyl-phosphonium bis(trifluoromethylsulfonyl)amide ([P14,6,6,6]Tf2N). Cyclic voltammetry and EQCM measurements show that, instead of elemental Ti, only non-stoichiometric halides are formed, …


Protein Dynamics And Stability: The Distribution Of Atomic Fluctuations In Thermophilic And Mesophilic Dihydrofolate Reductase Derived Using Elastic Incoherent Neutron Scattering, Lars Meinhold, David Clement, Moeava Tehei, Roy Daniel, John L. Finney, Jeremy C. Smith Jan 2008

Protein Dynamics And Stability: The Distribution Of Atomic Fluctuations In Thermophilic And Mesophilic Dihydrofolate Reductase Derived Using Elastic Incoherent Neutron Scattering, Lars Meinhold, David Clement, Moeava Tehei, Roy Daniel, John L. Finney, Jeremy C. Smith

Faculty of Science, Medicine and Health - Papers: part A

The temperature dependence of the dynamics of mesophilic and thermophilic dihydrofolate reductase is examined using elastic incoherent neutron scattering. It is demonstrated that the distribution of atomic displacement amplitudes can be derived from the elastic scattering data by assuming a (Weibull) functional form that resembles distributions seen in molecular dynamics simulations. The thermophilic enzyme has a significantly broader distribution than its mesophilic counterpart. Furthermore, although the rate of increase with temperature of the atomic mean-square displacements extracted from the dynamic structure factor is found to be comparable for both enzymes, the amplitudes are found to be slightly larger for the …


Clusterin Interacts With Paclitaxel And Confer Paclitaxel Resistance In Ovarian Cancer, Dong Choon Park, Seung Geun Yeo, Mark R. Wilson, Justin J. Yerbury, Joseph Kwong, William R. Welch, Yang Kyu Choi, Michael J. Birrer, Samuel C. Mok, Kwong-Kwok Wong Jan 2008

Clusterin Interacts With Paclitaxel And Confer Paclitaxel Resistance In Ovarian Cancer, Dong Choon Park, Seung Geun Yeo, Mark R. Wilson, Justin J. Yerbury, Joseph Kwong, William R. Welch, Yang Kyu Choi, Michael J. Birrer, Samuel C. Mok, Kwong-Kwok Wong

Faculty of Science - Papers (Archive)

Optimal debulking followed by chemotherapy is the standard treatment of managing late-stage ovarian cancer, but chemoresistance is still a major problem. In this study, we compared expression profiles of primary tumor tissue from five long-term (>8 years) and five short-term (years) ovarian cancer survivors and identified clusterin as one of the genes that were significantly up-regulated in short-term survivors. We then evaluated the prognostic significance of clusterin and its possible correlation with chemoresistance in ovarian cancer by immunohistostaining of clusterin in 62 tumor samples from patients with stage III, high-grade serous ovarian cancer. After adjusting for debulking status and …


Extracellular Chaperones And Amyloids, Mark R. Wilson, Justin J. Yerbury, Stephen Poon Jan 2008

Extracellular Chaperones And Amyloids, Mark R. Wilson, Justin J. Yerbury, Stephen Poon

Faculty of Science - Papers (Archive)

The pathology of more than 40 human degenerative diseases is associated with fibrillar proteinaceous deposits called amyloid. Collectively referred to as protein deposition diseases, many of these affect the brain and the central nervous system. In many cases the amyloid deposits are extracellular and are found associated with newly identified abundant extracellular chaperones (ECs). Evidence is discussed which suggests an important regulatory role for ECs in amyloid formation and disposal in vivo. This is emerging as an exciting field. A model is presented in which it is proposed that, under normal conditions, ECs stabilize extracellular misfolded proteins by binding to …


The Key Importance Of Soy Isoflavone Bioavailability To Understanding Health Benefits, T. A. Larkin, William E. Price, L. Astheimer Jan 2008

The Key Importance Of Soy Isoflavone Bioavailability To Understanding Health Benefits, T. A. Larkin, William E. Price, L. Astheimer

Faculty of Science - Papers (Archive)

Research over the past two decades has provided significant epidemiological and other evidence for the health benefits of the consumption of soy-based foods. A large number of dietary intervention studies have examined the effects of soy isoflavones on risk factors for cardiovascular disease and hormone-dependent cancers. However, these report large variability in outcome measures, very limited reproducibility between studies and in some cases, controversy between results of clinical trials using dietary soy or soy protein and isoflavone supplementation. This highlights a major gap in our understanding of soy isoflavone uptake, metabolism, distribution, and overall bioavailability. There are many potential factors …


Antimycobacterial Activity Of Cinnamate-Based Esters Of The Triterpenes Betulinic, Oleanolic And Ursolic Acids, Tanud Tanachatchairatana, John B. Bremner, Ratchanaporn Chokchaisiri, Apichart Suksamrarn Jan 2008

Antimycobacterial Activity Of Cinnamate-Based Esters Of The Triterpenes Betulinic, Oleanolic And Ursolic Acids, Tanud Tanachatchairatana, John B. Bremner, Ratchanaporn Chokchaisiri, Apichart Suksamrarn

Faculty of Science - Papers (Archive)

Betulinic acid, oleanolic acid and ursolic acid have been modified at the C-3 position to cinnamate-based esters and in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Ra has been determined. The results indicated that modification of the parent structures of betulinic acid, oleanolic acid and ursolic acid to the p-coumarate and, in the case of the latter two triterpenes, the ferulate ester analogues resulted in high antimycobacterial activity. Structure–activity relationships within the lupane, oleanane and ursane analogues and between these triterpenes are discussed.


Ozone Induced Dissociation: Elucidation Of Double Bond Position Within Mass-Selected Lipid Ions, Michael C. Thomas, Todd W. Mitchell, David G. Harman, Jane M. Deeley, Jessica R. Nealon, Stephen J. Blanksby Jan 2008

Ozone Induced Dissociation: Elucidation Of Double Bond Position Within Mass-Selected Lipid Ions, Michael C. Thomas, Todd W. Mitchell, David G. Harman, Jane M. Deeley, Jessica R. Nealon, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

Ions formed from lipids during electrospray ionization of crude lipid extracts have been mass-selected within a quadrupole linear ion trap mass spectrometer and allowed to react with ozone vapor. Gas-phase ion−molecule reactions between unsaturated lipid ions and ozone are found to yield two primary product ions for each carbon−carbon double bond within the molecule. The mass-to-charge ratios of these chemically induced fragments are diagnostic of the position of unsaturation within the precursor ion. This novel analytical technique, dubbed ozone-induced dissociation (OzID), can be applied both in series and in parallel with conventional collision-induced dissociation (CID) to provide near-complete structural assignment …


The Proofreading Exonuclease Subunit E Of Escherichia Coli Dna Polymerase Iii Is Tethered To The Polymerase Subunit A Via A Flexible Linker, Kiyoshi Ozawa, Slobodan Jergic, Ah-Young Park, Nicholas E. Dixon, Gottfried Otting Jan 2008

The Proofreading Exonuclease Subunit E Of Escherichia Coli Dna Polymerase Iii Is Tethered To The Polymerase Subunit A Via A Flexible Linker, Kiyoshi Ozawa, Slobodan Jergic, Ah-Young Park, Nicholas E. Dixon, Gottfried Otting

Faculty of Science - Papers (Archive)

Escherichia coli DNA polymerase III holoenzyme is composed of 10 different subunits linked by noncovalent interactions. The polymerase activity resides in the α-subunit. The ε-subunit, which contains the proofreading exonuclease site within its N-terminal 185 residues, binds to α via a segment of 57 additional C-terminal residues, and also to θ, whose function is less well defined. The present study shows that θ greatly enhances the solubility of ε during cell-free synthesis. In addition, synthesis of ε in the presence of θ and α resulted in a soluble ternary complex that could readily be purified and analyzed by …


Comparison Of Mass Spectrometry And Other Techniques For Probing Interactions Between Metal Complexes And Dna, Thitima Urathamakul, Daniel J. Waller, Jennifer L. Beck, Janice Aldrich-Wright, Stephen F. Ralph Jan 2008

Comparison Of Mass Spectrometry And Other Techniques For Probing Interactions Between Metal Complexes And Dna, Thitima Urathamakul, Daniel J. Waller, Jennifer L. Beck, Janice Aldrich-Wright, Stephen F. Ralph

Faculty of Science - Papers (Archive)

Electrospray ionization mass spectrometry (ESI-MS) was used to study the binding interactions of two series of ruthenium complexes, [Ru(phen)2L]2+ and [RuL′2(dpqC)]2+, to a double stranded DNA hexadecamer, and derive orders of relative binding affinity. These were shown to be in good agreement with orders of relative binding affinity derived from absorption and circular dichroism (CD) spectroscopic examination of the same systems and from DNA melting curves. However, the extent of luminescence enhancement caused by the addition of DNA to solutions of the ruthenium complexes showed little correlation with orders of binding affinity derived from ESI-MS or any of the other …


The Mitochondrial Genome Of The Stingless Bee Melipona Bicolor (Hymenoptera, Apidae, Meliponini): Sequence, Gene Organization And A Unique Trna Translocation Event Conserved Across The Tribe Meliponini, Daniela Silvestre, Mark P. Dowton, Maria C. Arias Jan 2008

The Mitochondrial Genome Of The Stingless Bee Melipona Bicolor (Hymenoptera, Apidae, Meliponini): Sequence, Gene Organization And A Unique Trna Translocation Event Conserved Across The Tribe Meliponini, Daniela Silvestre, Mark P. Dowton, Maria C. Arias

Faculty of Science - Papers (Archive)

No abstract provided.


Synthetic And Spectroscopic Studies On The Structures Of Uniflorines A And B: Structural Revision To 1,2,6,7-Tetrahydroxy-3-Hydroxymethylpyrrolizidine Alkaloids, Andrew S. Davis, Thunwadee Ritthiwigrom, Stephen G. Pyne Jan 2008

Synthetic And Spectroscopic Studies On The Structures Of Uniflorines A And B: Structural Revision To 1,2,6,7-Tetrahydroxy-3-Hydroxymethylpyrrolizidine Alkaloids, Andrew S. Davis, Thunwadee Ritthiwigrom, Stephen G. Pyne

Faculty of Science - Papers (Archive)

The diastereoselective synthesis of the C-2 epimer and the C-1, C-2 di-epimers of the putative structure of the alkaloid uniflorine A has been achieved. The synthesis of the latter di-epimers employed a novel pyrrolo[1,2-c]oxazin-1-one precursor to allow for the reversal of π-facial diastereoselectivity in an osmium(VIII)-catalyzed syn-dihydroxylation (DH) reaction. The NMR spectral data of these epimeric compounds and that of related isomers did not match that of the natural product. From a comparison of the NMR data of uniflorines A and B with that of casuarine and the known synthetic 1,2,6,7-tetrahydroxy-3-hydroxymethylpyrrolizidine isomers we concluded unequivocally that uniflorine …


Oxidative Coupling Of Indoles Using Thallium(Iii) Trifluoroacetate, Paul A. Keller, N. R. Yepuri, M. J. Kelso, M. Mariani, B. W. Skelton, A. H. White Jan 2008

Oxidative Coupling Of Indoles Using Thallium(Iii) Trifluoroacetate, Paul A. Keller, N. R. Yepuri, M. J. Kelso, M. Mariani, B. W. Skelton, A. H. White

Faculty of Science - Papers (Archive)

The oxidative coupling of polysubstituted electron-rich indoles mediated by thallium trifluoroacetate was found to be a facile, clean, and high yielding reaction. Indolic coupling sites were determined by the nature of the substituents present, with dimerisation at the indole 2-position being the dominant outcome. Indoles bearing two potential reaction sites with similar reactivity were additionally found to undergo heterocoupling.


Increased Probiotic Yogurt Or Resistant Starch Intake Does Not Affect Isoflavone Bioavailability In Subjects Consuming A High Soy Diet, Theresa A. Larkin, William E. Price, Lee B. Astheimer Oct 2007

Increased Probiotic Yogurt Or Resistant Starch Intake Does Not Affect Isoflavone Bioavailability In Subjects Consuming A High Soy Diet, Theresa A. Larkin, William E. Price, Lee B. Astheimer

Faculty of Science - Papers (Archive)

Objective: Probiotics and prebiotics that affect gut microflora balance and its associated enzymeactivity may contribute to interindividual variation in isoflavone absorption after soy intake, possiblyenhancing isoflavone bioavailability. This study examined the effects of the consumption ofbioactive yogurt (a probiotic) or resistant starch (a known prebiotic) in combination with high soyintake on soy isoflavone bioavailability.Methods: Using a crossover design, chronic soy consumption was compared with soy plusprobiotic yogurt or resistant starch in older male and postmenopausal females (n 31). Isoflavonebioavailability was assessed at the beginning and end of each 5-wk dietary period by samplingplasma and urine after a standardized soy meal.Results: …


Elucidation Of Double Bond Position In Unsaturated Lipids By Ozone Electrospray Ionization Mass Spectrometry (Ozesi-Ms), M. C. Thomas, Todd Mitchell, J. M. Deeley, D. G. Harman, R. C. Murphy, Stephen J. Blanksby Jun 2007

Elucidation Of Double Bond Position In Unsaturated Lipids By Ozone Electrospray Ionization Mass Spectrometry (Ozesi-Ms), M. C. Thomas, Todd Mitchell, J. M. Deeley, D. G. Harman, R. C. Murphy, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

The position(s) of carbon-carbon double bonds within lipids can dramatically affect their structure and reactivity and thus has a direct bearing on biological function. Commonly employed mass spectrometric approaches to the characterization of complex lipids however, fail to localize sites of unsaturation within the molecular structure and thus cannot distinguish naturally occurring regioisomers. In a recent communication [Thomas, Mitchell, Blanksby in the Journal of the American Chemical Society, 2006, 128, 58-59] we have presented a new technique for the elucidation of double bond position in glycerophospholipids using ozone-induced fragmentation within the source of a conventional electrospray ionization mass spectrometer. Here …


Control Of Hiv Through The Inhibition Of Hiv-1 Integrase: A Medicinal Chemistry Perspective, Christopher Gordon, R. Griffith, Paul A. Keller Mar 2007

Control Of Hiv Through The Inhibition Of Hiv-1 Integrase: A Medicinal Chemistry Perspective, Christopher Gordon, R. Griffith, Paul A. Keller

Faculty of Science - Papers (Archive)

This article reviews the current status of classes of HIV-1 integrase enzyme inhibitors. These classes include peptide-based inhibitors, natural products, polyhydroxylated aromatics, diketo acids, naphthyridines, and sulfonated compounds including sulfonic acids. Discussions of structure activity relationships are presented and include the current overview of the structure-based model, suitable for the further design and development. To date, the advances in the medicinal chemistry of HIV-1 integrase inhibitors have relied mostly on ligand-based designs leading to most displaying similar binding interactions within the active site or at the dimer interface. This paves the way for single enzyme mutations rendering entire compound classes …


The Plasminogen-Binding Group A Streptococcal M Protein-Related Protein Prp Binds Plasminogen Via Arginine And Histidine Residues, Martina L. Sanderson-Smith, M. Dowton, Marie Ranson, Mark J. Walker Feb 2007

The Plasminogen-Binding Group A Streptococcal M Protein-Related Protein Prp Binds Plasminogen Via Arginine And Histidine Residues, Martina L. Sanderson-Smith, M. Dowton, Marie Ranson, Mark J. Walker

Faculty of Science - Papers (Archive)

The migration of the human pathogen Streptococcus pyogenes (group A streptococcus) from localized to deep tissue sites may result in severe invasive disease, and sequestration of the host zymogen plasminogen appears crucial for virulence. Here, we describe a novel plasminogen-binding M protein, the plasminogen-binding group A streptococcal M protein (PAM)-related protein (Prp). Prp is phylogenetically distinct from previously described plasminogen-binding M proteins of group A, C, and G streptococci. While competition experiments indicate that Prp binds plasminogen with a lower affinity than PAM (50% effective concentration = 0.34 µM), Prp nonetheless binds plasminogen with high affinity and at physiologically relevant …


A New Methodology For The Simulation Of Flexible Protein – Ligand Interactions, James A. Garner, John Deadman, David I. Rhodes, Renate Griffith, Paul A. Keller Jan 2007

A New Methodology For The Simulation Of Flexible Protein – Ligand Interactions, James A. Garner, John Deadman, David I. Rhodes, Renate Griffith, Paul A. Keller

Faculty of Science - Papers (Archive)

A methodology has been developed for the simulation of induced fit between a ligand and its target protein. It utilizes constrained molecular dynamics where atoms determined to be immobile from difference distance matrix studies are fixed. Application of this methodology to HIV-1 reverse transcriptase (RT) as the example target protein has demonstrated its robustness. Short simulation times are sufficient to achieve good refinement of docking poses resulting from exchange of structurally dissimilar inhibitors between crystal structures.


Detection Of Al(Iii) And Ga(Iii) Complexes With Morin By Electrospray Ionization Mass Spectrometry, John B. Bremner, Larry A. Hick, Jody Morgan, Saowanee Rattanaphani, Vichitr Rattanaphani, C Septhum Jan 2007

Detection Of Al(Iii) And Ga(Iii) Complexes With Morin By Electrospray Ionization Mass Spectrometry, John B. Bremner, Larry A. Hick, Jody Morgan, Saowanee Rattanaphani, Vichitr Rattanaphani, C Septhum

Faculty of Science - Papers (Archive)

The Al(III) and Ga(III) complexes formed by morin (M) in aqueous solution were investigated by means of electrospray ionization mass spectrometry (ESI-MS). In the full scan mass spectra, Al:M showed 1:2 and 2:3 stoichiometric ratios. When (S)-N-acetylserine methyl ester (Ser), as a partial mimic of the serine residue in silk, was added to Al:M and Ga:M complexes in aqueous solution, the mass spectra of Ser:Al:M showed 1:1:1 and 1:1:2 stoichiometric ratios. The patterns of the mass spectra of Ga:M and Ser:Ga:M complexes were similar to those for the corresponding Al(III) complexes. Calculated heats of formation of potential structures of the …


Stress-Induced Retrotranslocation Of Clusterin/Apoj Into The Cytosol, P Nizard, Suzanne Tetley, Y Le Drean, T Watrin, P Le Goff, Mark R. Wilson, Denis Michel Jan 2007

Stress-Induced Retrotranslocation Of Clusterin/Apoj Into The Cytosol, P Nizard, Suzanne Tetley, Y Le Drean, T Watrin, P Le Goff, Mark R. Wilson, Denis Michel

Faculty of Science - Papers (Archive)

Clusterin is a usually secreted glycoprotein with chaperone properties. Recently, it has been suggested that clusterin isoforms reside in the nuclear and cytosolic compartments of human cell types, where they can influence various cellular programs including DNA repair, transcription and apoptosis. Several mechanisms have been proposed to explain this atypical location, including alternative transcription initiation and alternative splicing. However none of these have been unequivocally established as occurring in live cells. Here we provide direct experimental evidence that in live intact cells, under certain stress conditions, clusterin can evade the secretion pathway and reach the cytosol. This was demonstrated using …


Syntheses Of Spiro[Cyclopropane-1,3'-Oxindole]-2-Carboxylic Acid And Cyclopropa[C]Quinoline-7b-Carboxylic Acid And Their Derivatives, Sarah Yong, Alison T. Ung, Stephen G. Pyne, Brian W. Skelton, Allan H. White Jan 2007

Syntheses Of Spiro[Cyclopropane-1,3'-Oxindole]-2-Carboxylic Acid And Cyclopropa[C]Quinoline-7b-Carboxylic Acid And Their Derivatives, Sarah Yong, Alison T. Ung, Stephen G. Pyne, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

The synthesis of spiro[cyclopropane-1,3′-oxindole]-2-carboxylic acid, including novel 3-(2- and 3-pyridyl)-substituted analogues and the novel cyclopropa[c]quinoline-7b-carboxylic acid and their ester and amide derivatives is described. These syntheses involve diastereoselective cyclopropanation reactions of methyl 2-(2-nitrophenyl)acrylate and (3E)-(pyridin-2-ylmethylene)- and (3E)-(pyridin-3-ylmethylene)-1,3-dihydro-2H-indol-2-one with ethyl (dimethyl sulfuranylidene) acetate (EDSA). The synthesis of methyl cyclopropa[c]quinoline-7b-carboxylate involves a regioselective reductive cyclization of a nitro-diester precursor. The relative stereochemistry of key compounds has been determined by single-crystal X-ray structural analysis.


Synthesis Of Benzo[C]Chromen-6-Ones Via Novel Cyclic Aryl-Pd(Ii)-Ester Enolate Intermediates, Stephen R. Taylor, Alison T. Ung, Stephen G. Pyne Jan 2007

Synthesis Of Benzo[C]Chromen-6-Ones Via Novel Cyclic Aryl-Pd(Ii)-Ester Enolate Intermediates, Stephen R. Taylor, Alison T. Ung, Stephen G. Pyne

Faculty of Science - Papers (Archive)

The examination of the palladium catalysed arylation reactions of mono-iodo derivatives of the phenyl and benzyl esters of benzoic acid, phenylacetic acid and dehydrocinnamic acid has resulted in the formation of benzo[c]chromen-6-ones, unexpected cinnamate and succinate products and diphenyl dimers. Many of these products can be rationalized as arising from novel cyclic ArPd(II)-enolate intermediates, formed by intramolecular C-H activation by ArPd(II).


Solution Structure Of Domains Iva And V Of The Tau Subunit Of Escherichia Coli Dna Polymerase Iii And Interaction With The Alpha Subunit, Xun-Cheng Su, Slobodan Jergic, Max A Keniry, Nicholas E. Dixon, Gottfried Otting Jan 2007

Solution Structure Of Domains Iva And V Of The Tau Subunit Of Escherichia Coli Dna Polymerase Iii And Interaction With The Alpha Subunit, Xun-Cheng Su, Slobodan Jergic, Max A Keniry, Nicholas E. Dixon, Gottfried Otting

Faculty of Science - Papers (Archive)

The solution structure of the C-terminal Domain V of the τ subunit of E. coli DNA polymerase III was determined by nuclear magnetic resonance (NMR) spectroscopy. The fold is unique to τ subunits. Amino acid sequence conservation is pronounced for hydrophobic residues that form the structural core of the protein, indicating that the fold is representative for τ subunits from a wide range of different bacteria. The interaction between the polymerase subunits τ and α was studied by NMR experiments where α was incubated with full-length C-terminal domain (τC16), and domains shortened at the C-terminus by 11 …


The Repressor Element 1-Silencing Transcription Factor Regulates Heart-Specific Gene Expression Using Multiple Chromatin-Modifying Complexes, Andrew J. Bingham, Lezanne Ooi, Lukasz Kozera, Edward White, Ian C. Wood Jan 2007

The Repressor Element 1-Silencing Transcription Factor Regulates Heart-Specific Gene Expression Using Multiple Chromatin-Modifying Complexes, Andrew J. Bingham, Lezanne Ooi, Lukasz Kozera, Edward White, Ian C. Wood

Faculty of Science - Papers (Archive)

Cardiac hypertrophy is associated with a dramatic change in the gene expression profile of cardiac myocytes. Many genes important during development of the fetal heart but repressed in the adult tissue are reexpressed, resulting in gross physiological changes that lead to arrhythmias, cardiac failure, and sudden death. One transcription factor thought to be important in repressing the expression of fetal genes in the adult heart is the transcriptional repressor REST (repressor element 1-silencing transcription factor). Although REST has been shown to repress several fetal cardiac genes and inhibition of REST function is sufficient to induce cardiac hypertrophy, the molecular mechanisms …


Mimicking Phosphorylation Of Alphab-Crystallin Affects Its Chaperone Activity, Heath W. Ecroyd, Sarah Meehan, J Horwitz, Andrew Aquilina, J L Benesch, C V Robinson, Cait Macphee, John Carver Jan 2007

Mimicking Phosphorylation Of Alphab-Crystallin Affects Its Chaperone Activity, Heath W. Ecroyd, Sarah Meehan, J Horwitz, Andrew Aquilina, J L Benesch, C V Robinson, Cait Macphee, John Carver

Faculty of Science - Papers (Archive)

No abstract provided.


Potential Roles Of Abundant Extracellular Chaperones In The Control Of Amyloid Formation And Toxicity, Mark R. Wilson, Justin J. Yerbury, Stephen Poon Jan 2007

Potential Roles Of Abundant Extracellular Chaperones In The Control Of Amyloid Formation And Toxicity, Mark R. Wilson, Justin J. Yerbury, Stephen Poon

Faculty of Science - Papers (Archive)

The in vivo formation of fibrillar proteinaceous deposits called amyloid is associated with more than 40 serious human diseases, collectively referred to as protein deposition diseases. In many cases the amyloid deposits are extracellular and are found associated with newly identified abundant extracellular chaperones (ECs). Evidence is presented suggesting an important regulatory role for ECs in amyloid formation and disposal in the body. A model is presented which proposes that, under normal conditions, ECs stabilize extracellular misfolded proteins by binding to them, and then guide them to specific cell receptors for uptake and subsequent degradation. Thus ECs and their receptors …


Air-Drying Of Banana: Influence Of Experimental Parameters, Slab Thickness, Banana Maturity And Harvesting Season, Minh-Hue Nguyen, William E. Price Jan 2007

Air-Drying Of Banana: Influence Of Experimental Parameters, Slab Thickness, Banana Maturity And Harvesting Season, Minh-Hue Nguyen, William E. Price

Faculty of Science - Papers (Archive)

Air-drying of banana slabs has been investigated and the influence of experimental parameters such as temperature, relative humidity and slab thickness has been studied. This was in part re-investigated because of inconsistencies in previous studies, particularly in relation to derived water diffusion coefficients. In addition, it is shown that harvest season and hence initial moisture content has a very marked influence on the drying kinetics. By contrast banana maturity (ripeness) has little influence on the kinetics despite there being significant differences in morphology and chemical composition between green and ripe bananas. The effect of these two variables on the drying …


The Importance Of Slime: Does Living In A Community Matrix Save Algal Cells From The Toxic Effects Of Copper?, Jacqueline Levy, Dianne F. Jolley, Jenny L. Stauber Jan 2007

The Importance Of Slime: Does Living In A Community Matrix Save Algal Cells From The Toxic Effects Of Copper?, Jacqueline Levy, Dianne F. Jolley, Jenny L. Stauber

Faculty of Science - Papers (Archive)

Microscopic algae are often used to assess the toxic effects of chemicals to the environment. They are good indicators of ecosystem health because they form the basis of the aquatic food chain and many algal species are sensitive to metals, like copper, at concentrations which occur naturally in the environment. Most toxicity tests with algae use planktonic species, that is, alga that live in the water as free-living species. To date, little research has been done on the toxicity of metals to attached algal species living in a community matrix known as biofilms, because of the difficulties in quantifying changes …