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Full-Text Articles in Physical Sciences and Mathematics
Kinase Inhibitory, Haemolytic And Cytotoxic Activity Of Three Deep-Water Sponges From North Western Australia And Their Fatty Acid Composition, Ana Zivanovic, Natalie J. Pastro, Jane Fromont, Murray Thomson, Danielle Skropeta
Kinase Inhibitory, Haemolytic And Cytotoxic Activity Of Three Deep-Water Sponges From North Western Australia And Their Fatty Acid Composition, Ana Zivanovic, Natalie J. Pastro, Jane Fromont, Murray Thomson, Danielle Skropeta
Danielle Skropeta
The c-AMP dependent protein kinase (PKA) inhibition, haemolytic activity, and cytoxicity of 21 extracts obtained from North Western Australian sponges collected from depths of 84-135 m were investigated. Hexane extracts from Ircinia/Sarcotragus sp. and Geodia sp. displayed PKA inhibitory activities of 100 and 97% respectively (at 100 μg/mL), while aq. methanol extracts from Haliclona sp. exhibited potent haemolytic activity (75%) and hexane extracts from Geodia sp. were highly toxic (88%) to the brine shrimp Artemia franciscana. As the non-polar extracts gave the greatest PKA inhibition, these were further analysed by GC-MS and 29 fatty acids were identified in the highest …
Deep-Sea Natural Products, Danielle Skropeta
Deep-Sea Natural Products, Danielle Skropeta
Danielle Skropeta
This review covers the 390 novel marine natural products described to date from deep-water (>50 m)marine fauna, with details on the source organism, its depth and country of origin, along with anyreported biological activity of the metabolites. Relevant synthetic studies on the deep-sea naturalproducts have also been included.
Misidentification Of Tansy, Tanacetum Macrophyllum, As Yarrow, Achillea Grandifolia: A Health Risk Or Benefit?, Niko Radulovic, Polina Blagojevic, Danielle Skropeta, Aleksandra Zarubica, Bojan Zlatkovic, Radosav Palic´
Misidentification Of Tansy, Tanacetum Macrophyllum, As Yarrow, Achillea Grandifolia: A Health Risk Or Benefit?, Niko Radulovic, Polina Blagojevic, Danielle Skropeta, Aleksandra Zarubica, Bojan Zlatkovic, Radosav Palic´
Danielle Skropeta
Tansy, Tanacetum macrophyllum (Waldst. & Kit.) Sch. Bip., is often misidentified by herb collectors as yarrow, Achillea grand folia Friv. With the former, cases of poisoning induced by its ingestion are well documented, but the latter is widely used for ethnopharmacological purposes. The aim of this study was to estimate, based on the volatile metabolite profiles of the two species, the potential health risk connected with their misidentification. GC and GC-MS analysis of the essential oils hydrodistilled using a Clevenger-type apparatus from A. grandifolia, T macrophyllum, and two plant samples (reputedly of A. grandifolia, but in fact mixtures of A. …
Anti-Cancer Activity Of An Acid-Labile N-Alkylisatin Conjugate Targeting The Transferrin Receptor, Vineesh Indira Chandran, Lidia Matesic, Julie Locke, Danielle Skropeta, Marie Ranson, Kara Vine
Anti-Cancer Activity Of An Acid-Labile N-Alkylisatin Conjugate Targeting The Transferrin Receptor, Vineesh Indira Chandran, Lidia Matesic, Julie Locke, Danielle Skropeta, Marie Ranson, Kara Vine
Danielle Skropeta
We have previously reported a series of pH-sensitive imine-linked N-alkylisatin prodrugs that are stable at pH 7.4, but readily cleaved at pH 4.5. Herein, one of the most potent prodrugs, 5,7-dibromo-N-(pmethoxybenzyl) isatin (NAI), was functionalized with a para-phenylpropionic acid linker, and the resulting NAI–imine prodrug conjugated to transferrin (Tf) to form a NAI–imine–Tf conjugate. Cytotoxicity assays revealed the conjugate was equipotent to the free drug against MCF-7 breast cancer cells, with clear selectivity patterns based on TfR levels. These results suggest that this novel isatin-based cytotoxin conjugated to a tumor targeting protein via an acid-labile linker warrants further preclinical testing.
Kinase Inhibitors From Marine Sponges, Danielle Skropeta, Natalie Pastro, Ana Zivanovic
Kinase Inhibitors From Marine Sponges, Danielle Skropeta, Natalie Pastro, Ana Zivanovic
Danielle Skropeta
Protein kinases play a critical role in cell regulation and their deregulation is a contributing factor in an increasing list of diseases including cancer. Marine sponges have yielded over 70 novel compounds to date that exhibit significant inhibitory activity towards a range of protein kinases. These compounds, which belong to diverse structural classes, are reviewed herein, and ordered based upon the kinase that they inhibit. Relevant synthetic studies on the marine natural product kinase inhibitors have also been included.
The Effect Of Individual N-Glycans On Enzyme Activity, Danielle Skropeta
The Effect Of Individual N-Glycans On Enzyme Activity, Danielle Skropeta
Danielle Skropeta
No abstract provided.
Structures, Biological Activities And Phylogenetic Relationships Of Terpenoids From Marine Ciliates Of The Genus Euplotes, Graziano Guella, Danielle Skropeta, Graziano Di Giuseppe, Fernando Dini
Structures, Biological Activities And Phylogenetic Relationships Of Terpenoids From Marine Ciliates Of The Genus Euplotes, Graziano Guella, Danielle Skropeta, Graziano Di Giuseppe, Fernando Dini
Danielle Skropeta
In the last two decades, large scale axenic cell cultures of the marine species comprising the family Euplotidae have resulted in the isolation of several new classes of terpenoids with unprecedented carbon skeletons including the (i) euplotins, highly strained acetylated sesquiterpene hemiacetals; (ii) raikovenals, built on the bicyclo[3.2.0]heptane ring system; (iii) rarisetenolides and focardins containing an octahydroazulene moiety; and (iv) vannusals, with a unique C-30 backbone. Their complex structures have been elucidated through a combination of nuclear magnetic resonance spectroscopy, mass spectrometry, molecular mechanics and quantum chemical calculations. Despite the limited number of biosynthetic experiments having been performed, the large …
Domino Pericyclic Reactions Of Acyclic Conjugated (E,Z,E,E)-Tetraenes, Danielle Skropeta, Rodney Rickards
Domino Pericyclic Reactions Of Acyclic Conjugated (E,Z,E,E)-Tetraenes, Danielle Skropeta, Rodney Rickards
Danielle Skropeta
No abstract provided.
N-Phenethyl And N-Naphthylmethyl Isatins And Analogues As In Vitro Cytotoxic Agents, John Bremner, Stephen Pyne, Marie Ranson, Danielle Skropeta, Julie Locke, Lidia Matesic, Kara Perrow
N-Phenethyl And N-Naphthylmethyl Isatins And Analogues As In Vitro Cytotoxic Agents, John Bremner, Stephen Pyne, Marie Ranson, Danielle Skropeta, Julie Locke, Lidia Matesic, Kara Perrow
Danielle Skropeta
Arange of N-phenethyl,N-phenacyl, and N-(1- and 2-naphthylmethyl) derivatives of 5,7-dibromoisatin 2 were prepared byN-alkylation reactions. Their activity against human monocyte-like histiocytic lymphoma (U937), leukemia (Jurkat), and breast carcinoma (MDA-MB-231) cell lines was assessed. The results allowed further development of structureactivity relationships. The compound 5,7-dibromo-N-(1-naphthylmethyl)-1H-indole-2,3-dione 5a was the most potent against U937 cells with an IC50 value of 0.19 microM.
Exploring Marine Resources For New Pharmaceutical Applications, Danielle Skropeta
Exploring Marine Resources For New Pharmaceutical Applications, Danielle Skropeta
Danielle Skropeta
No abstract provided.
Complete Assignment Of The 1h And 13c Nmr Spectra Of Antimicrobial 4-Arylamino- 3-Nitrocoumarin Derivatives, Vidoslav Dekic, Niko Radulovic, Rastko Vukicevic, Biljana Dekic, Danielle Skropeta, Radosav Palic
Complete Assignment Of The 1h And 13c Nmr Spectra Of Antimicrobial 4-Arylamino- 3-Nitrocoumarin Derivatives, Vidoslav Dekic, Niko Radulovic, Rastko Vukicevic, Biljana Dekic, Danielle Skropeta, Radosav Palic
Danielle Skropeta
No abstract provided.
Synthesis And Hydrolytic Evaluation Of Acid-Labile Imine-Linked Cytoxic Isatin Model Systems, Lidia Matesic, Julie Locke, Kara Perrow, Marie Ranson, John Bremner, Danielle Skropeta
Synthesis And Hydrolytic Evaluation Of Acid-Labile Imine-Linked Cytoxic Isatin Model Systems, Lidia Matesic, Julie Locke, Kara Perrow, Marie Ranson, John Bremner, Danielle Skropeta
Danielle Skropeta
In this study a series of isatin-based, pH-sensitive aryl imine derivatives with differing aromatic substituents and substitution patterns were synthesised and their acid-catalysed hydrolysis evaluated. These derivatives were functionalised at the C3 carbonyl group of a potent N-substituted isatin cytotoxin and were stable at physiological pH but readily cleaved at pH 4.5. Observed rates of hydrolysis for the embedded imine-acid moiety were in the order para-phenylpropionic acid>phenylacetic acid (para>meta)>benzoic acid (meta>para). The ability to fine-tune hydrolysis rates in this way has potential implications for optimising imine linked, tumour targeting cytotoxin-protein conjugates
Average Mass Scan Of The Total Ion Chromatogram Versus Percentage Chemical Composition In Multivariate Statistical Comparison Of Complex Volatile Mixtures, Niko Radulovic, Polina Blagojevic, Danielle Skropeta
Average Mass Scan Of The Total Ion Chromatogram Versus Percentage Chemical Composition In Multivariate Statistical Comparison Of Complex Volatile Mixtures, Niko Radulovic, Polina Blagojevic, Danielle Skropeta
Danielle Skropeta
The analysis of complex volatile mixtures by gas chromatography-mass spectrometry (GC-MS) is a time-consuming process. It involves separation and identification of the components based on their retention times and fragmentation patterns, followed by determination of their relative percentages from integration of their peak areas. Herein we show that multivariate statistical analysis of the relative abundances of the m/z values obtained from the average mass scans (AMS) of the complex mixture is a faster and potentially more reliable method of assessing these mixtures. To achieve this, 15 model complex mixtures, were prepared comprising varying amounts of 10 different constituents. The AMS …
Synthesis And Anti-Leukaemic Activity Of Pyrrolo[3,2,1-Hi]Indole-1,2- Diones, Pyrrolo[3,2,1-Ij]Quinoline-1,2-Diones And Other Polycyclic Isatin Derivatives, Lidia Matesic, Julie M. Locke, Kara Vine, Marie Ranson, John B. Bremner, Danielle Skropeta
Synthesis And Anti-Leukaemic Activity Of Pyrrolo[3,2,1-Hi]Indole-1,2- Diones, Pyrrolo[3,2,1-Ij]Quinoline-1,2-Diones And Other Polycyclic Isatin Derivatives, Lidia Matesic, Julie M. Locke, Kara Vine, Marie Ranson, John B. Bremner, Danielle Skropeta
Danielle Skropeta
To further expand the structure–cytotoxic activity relationships of isatin derivatives and to reduce flexibility in substituent groups at nitrogen, 20 analogues incorporating a ring system between the N1 and C7 atoms of isatin were prepared using a variety of synthetic strategies. This yielded pyrroloindole-, pyrroloquinoline-, pyrroloacridine-, pyrrolophenanthridine- and benzopyrrolophenanthridine-based systems with embedded isatin moieties, the latter possessing a novel carbon skeleton. These compounds were subsequently assessed for their in vitro cytotoxicity against human U937 lymphoma cells, with the brominated pyrroloacridine dione 27 showing the most promising activity (IC50 3.01 μM) after 24 h.
N-Glycolisation Regulates Endothelial Lipase-Mediated Phospholipid Hydrolysis In Apoe- And Apoa-I-Containing High Density Lipoproteins, Danielle Skropeta, Daniel Rader, Weijun Jin, Monica Mcmahon, Kate Shearston, Philip Barter, Kristine Mcgrath, Kerry-Anne Rye, Chatri Settasatian, Daniela Caiazza
N-Glycolisation Regulates Endothelial Lipase-Mediated Phospholipid Hydrolysis In Apoe- And Apoa-I-Containing High Density Lipoproteins, Danielle Skropeta, Daniel Rader, Weijun Jin, Monica Mcmahon, Kate Shearston, Philip Barter, Kristine Mcgrath, Kerry-Anne Rye, Chatri Settasatian, Daniela Caiazza
Danielle Skropeta
No abstract provided.
Cytotoxic And Anticancer Activities Of Isatin And Its Derivatives: A Comprehensive Review From 2000-2008, Marie Ranson, Danielle Skropeta, Julie Locke, Lidia Matesic, Kara Perrow
Cytotoxic And Anticancer Activities Of Isatin And Its Derivatives: A Comprehensive Review From 2000-2008, Marie Ranson, Danielle Skropeta, Julie Locke, Lidia Matesic, Kara Perrow
Danielle Skropeta
No abstract provided.
Chemotaxonomy Of The Peppergrass Lepidium Coronopus (L.) Al-Shehbaz (Syn. Coronopus Squamatus) Based On Its Volatile Glucosinolate Autolysis Products, Niko Radulovic, Bojan Zlatkovic, Danielle Skropeta, Radosav Palic´
Chemotaxonomy Of The Peppergrass Lepidium Coronopus (L.) Al-Shehbaz (Syn. Coronopus Squamatus) Based On Its Volatile Glucosinolate Autolysis Products, Niko Radulovic, Bojan Zlatkovic, Danielle Skropeta, Radosav Palic´
Danielle Skropeta
The genus Lepidium comprises approximately 175 different plant species commonly referred to as peppergrasses or pepperworts ( Al-Shehbaz, 1997 and Mummenhoff et al., 2001), which occur worldwide apart from the polar regions where they are considered rare in the Arctic and are absent from Antarctica. Lepidium is a comparatively large genus belonging to the mustard family Brassicaceae. Lepidium coronopus (L.) Al-Shehbaz, a representative of the genus, is a herbaceous annual to biennial plant that belongs to the tribe Lepidieae and has previously been described by the following synonymous species: Coronopus squamatus (Forsskal) Ascherson; C. squamatus subsp. conradi (Muschler) Maire; C. …
Learning How To Be An Academic - The Story Of A New Academic In The Sciences, Danielle Skropeta
Learning How To Be An Academic - The Story Of A New Academic In The Sciences, Danielle Skropeta
Danielle Skropeta
No abstract provided.
Solid-State And Solution-Phase Conformations Of Pseudoproline-Containing Dipeptides, James R. Cochrane, Nima Sayyadi, Danielle Skropeta, Peter Turner, Jack K. Clegg, Katrina A. Jolliffe
Solid-State And Solution-Phase Conformations Of Pseudoproline-Containing Dipeptides, James R. Cochrane, Nima Sayyadi, Danielle Skropeta, Peter Turner, Jack K. Clegg, Katrina A. Jolliffe
Danielle Skropeta
The conformations of 14 threonine-derived pseudoproline-containing dipeptides (including four d-allo-Thr derivatives) have been investigated by NMR. In solution, the major conformer observed for all dipeptides is that in which the amide bond between the pseudoproline and the preceding amino acid is cis. For dipeptides in which the N-terminus is protected, the ratio of cis- to trans-conformers does not depend significantly on the side chain of the N-terminal amino acid, or the stereochemistry of the Thr residue. However, for dipeptides bearing a free N-terminus, there are significant differences in the ratios of cis- to trans-conformers depending on the side chain present. …
Synthesis Of Reaction-Ready 6,6 '-Biindole And 6,6 '-Biisatin Via Palladium(Ii)-Catalysed Intramolecular C-H Functionalisation, Allan B. Gamble, Paul A. Keller
Synthesis Of Reaction-Ready 6,6 '-Biindole And 6,6 '-Biisatin Via Palladium(Ii)-Catalysed Intramolecular C-H Functionalisation, Allan B. Gamble, Paul A. Keller
Paul Keller
The first synthesis of a 6,6'-biindole and 6,6'-biisatin scaffold is reported with the penultimate step being the formation of the di-heterocyclic ring by Pd(II)-catalysed intramolecular C-H functionalisation and Sandmeyer cyclisation, respectively.
The First Syntheses Of Enantiopure 2,2 '-Biindoline, Steven M. Wales, Anthony C. Willis, Paul A. Keller
The First Syntheses Of Enantiopure 2,2 '-Biindoline, Steven M. Wales, Anthony C. Willis, Paul A. Keller
Paul Keller
The first two syntheses of chiral 2,2'-biindoline are reported either in five steps from 2,2'-bioxirane, or three steps from 2,2'-biaziridine, both with exceptional enantiopurity
Reductive Ring Opening Reactions Of Diphenyldihydrofullerenylpyrroles, William Hawkins, Paul A. Keller, Stephen G. Pyne
Reductive Ring Opening Reactions Of Diphenyldihydrofullerenylpyrroles, William Hawkins, Paul A. Keller, Stephen G. Pyne
Paul Keller
The reductive ring opening reaction conditions for the simple [60]fullerenyldihydropyrrole 1 have been optimized to include acetic acid in the reaction mixture to rapidly protonate the anionic intermediate. Under these conditions, the ring opened dihydrofullerene 2 was obtained in 68% yield. Under slightly modified conditions and at −78 °C, the reductive bis-ring opening of the tethered trans-4 isomer 3 provided the novel racemic bis-dihydrofullerenyl derivative 7.
Revealing Indigenous Indonesian Traditional Medicine: Anti-Infective Agents, Paul A. Keller, Ari Satia Nugraha
Revealing Indigenous Indonesian Traditional Medicine: Anti-Infective Agents, Paul A. Keller, Ari Satia Nugraha
Paul Keller
Indonesia is rich in medicinal plants which the population has used traditionally from generation to generation for curing diseases. Our interest in the treatment of infectious diseases has lead to the investigation of traditional Indonesian treatments. In this review, we present a comprehensive review of ethnopharmacologically directed screening in Indonesian medicinal plants to search for new anti-viral, antimalarial, anti-bacterial and anti-fungal agents. Some potent drug leads have been isolated from Indonesian medicinal plants. Further research is still required for the lead development as well as the search for new bioactive compounds from the enormous medicinal plant resources.
Binaphthyl-Anchored Antibacterial Tripeptide Derivatives With Hydrophobic C-Terminal Amino Acid Variations, John Bremner, Paul A. Keller, Stephen Pyne, Mark Robertson, Kandasamy Sakthivel, Kittiya Somphol, Dean Baylis, Jonathon A Coates, John Deadman, Dharshini Jeevarajah, David I. Rhodes
Binaphthyl-Anchored Antibacterial Tripeptide Derivatives With Hydrophobic C-Terminal Amino Acid Variations, John Bremner, Paul A. Keller, Stephen Pyne, Mark Robertson, Kandasamy Sakthivel, Kittiya Somphol, Dean Baylis, Jonathon A Coates, John Deadman, Dharshini Jeevarajah, David I. Rhodes
Paul Keller
The facile synthesis of seven new dicationic tripeptide benzyl ester derivatives, with hydrophobic group variations in the C-terminal amino acid component, is described. Moderate to good activity was seen against Gram-positive bacteria in vitro. One cyclohexyl-substituted compound 2c was tested more widely and showed good potency (MIC values ranging from 2–4 μg/mL) against antibiotic-resistant strains of Staphylococcus aureus and Enterococci (VRE, VSE), and against Staphylococcus epidermidis.
Synthesis Of Novel N-Protected Hydrophobic Phenylalanines And Their Application In Potential Antibacterials, Timothy P. Boyle, J. B. Bremner, Jonathan A. Coates, John Deadman, Paul A. Keller, Stephen G. Pyne, Kittiya Somphol
Synthesis Of Novel N-Protected Hydrophobic Phenylalanines And Their Application In Potential Antibacterials, Timothy P. Boyle, J. B. Bremner, Jonathan A. Coates, John Deadman, Paul A. Keller, Stephen G. Pyne, Kittiya Somphol
Paul Keller
An efficient synthesis of two new N-acetyl-4’-arylphenylalanines is described together with their incorporation in to a number of cationic peptoid antibacterial agents, one of which had an MIC of 7.8 μg/mL against Staphylococcus aureus.
Phytochemical And Biological Activity Studies Of The Bhutanese Medicinal Plant Corydalis Crispa, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Thanapat Sastraruji, Malai Taweechotipatr, Roonglawan Rattanajak, Aunchalee Tonsomboon, Sumalee Kamchonwongpaisan
Phytochemical And Biological Activity Studies Of The Bhutanese Medicinal Plant Corydalis Crispa, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Thanapat Sastraruji, Malai Taweechotipatr, Roonglawan Rattanajak, Aunchalee Tonsomboon, Sumalee Kamchonwongpaisan
Paul Keller
The chemical constituents and biological activities of Corydalis crispa (Fumariaceae) were investigated for the first time. The phytochemical study resulted in the isolation of nine known isoquinoline alkaloids: protopine (1), 13-oxoprotopine (2), 13-oxocryptopine (3), stylopine (4), coreximine (5), rheagenine (6), ochrobirine (7), sibiricine (8) and bicuculline (9), with complete NMR data for 2 and 3 provided here for the first time. Crude extracts exhibitedsignificant anti-inflammatory (p < 0.01) activity against TNF-alpha production in LPS activated THP-1 cells. The acetylcholinesterase inhibitory activity of compounds 2, 4 and 7 and the antiplasmodial activity of compound 5 against P. falciparum strains TM4/8.2 and K1CB1 …
Antimalarial Alkaloids From A Bhutanese Traditional Medicinal Plant Corydalis Dubia, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Anthony C. Willis, Sumalee Kamchonwongpaisan
Antimalarial Alkaloids From A Bhutanese Traditional Medicinal Plant Corydalis Dubia, Phurpa Wangchuk, Paul A. Keller, Stephen G. Pyne, Anthony C. Willis, Sumalee Kamchonwongpaisan
Paul Keller
Ethnopharmacological relevance: Corydalis dubia is used in Bhutanese traditional medicine as a febrifuge and for treating infections in the blood, liver and bile which correlate to the signs and symptoms of malarial and microbial infections. Aim of the study: To validate the ethnopharmacological uses of the plant and to discover potential new therapeutic drug leads. Materials and methods C. dubia was collected from Bhutan and the alkaloids were obtained using acid–base fractionation and separation by repeated column and preparative plate chromatography. The alkaloids were identified from analysis of their physiochemical and spectroscopic data and were tested for antiplasmodial, antimicrobial and …
Structural Re-Assignment Of The Mono- And Bis-Addition Products From The Addition Reactions Of N-(Diphenylmethylene)Glycinate Esters To [60]Fullerene Under Bingel Conditions, Graham E Ball, Glenn Ashley Burley, Leila Chaker, William Hawkins, James Williams, Paul A. Keller, Stephen G. Pyne
Structural Re-Assignment Of The Mono- And Bis-Addition Products From The Addition Reactions Of N-(Diphenylmethylene)Glycinate Esters To [60]Fullerene Under Bingel Conditions, Graham E Ball, Glenn Ashley Burley, Leila Chaker, William Hawkins, James Williams, Paul A. Keller, Stephen G. Pyne
Paul Keller
The addition of N-(diphenylmethylene)glycinate esters (Ph2C=NCH2CO2R) to [60]fullerene under Bingel conditions gives [60]fullerenyldihydropyrroles and not methano[60]fullerenyl iminoesters [C60C(CO2R)(N=CPh2)] as previously reported. Unequivocal evidence for the structure of C60C(CO2Et)(N=CPh2) was provided by INADEQUATE NMR studies on 13C enriched material. New mechanistic details are proposed to account for the formation of [60]fullerenyldihydropyrroles and their reductive ring-opening reactions.
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
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
Professor Nick E Dixon
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 and 18 residues, …
Effect Of Protein Stabilization On Charge State Distribution In Positive- And Negative Ion Electrospray Ionization Mass Spectra, Stephen J. Watt, Margaret Sheil, Jennifer L. Beck, Pavel Prosselkov, Gottfried Otting, Nicholas E. Dixon
Effect Of Protein Stabilization On Charge State Distribution In Positive- And Negative Ion Electrospray Ionization Mass Spectra, Stephen J. Watt, Margaret Sheil, Jennifer L. Beck, Pavel Prosselkov, Gottfried Otting, Nicholas E. Dixon
Professor Nick E Dixon
Changes in protein conformation are thought to alter charge state distributions observed in electrospray ionization mass spectra (ESI-MS) of proteins. In most cases, this has been demonstrated by unfolding proteins through acidification of the solution. This methodology changes the properties of the solvent so that changes in the ESI-MS charge envelopes from conformational changes are difficult to separate from the effects of changing solvent on the ionization process. A novel strategy is presented enabling comparison of ESI mass spectra of a folded and partially unfolded protein of the same amino acid sequence subjected to the same experimental protocols and conditions. …