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Full-Text Articles in Social and Behavioral Sciences
Enzyme Activity And Flexibility At Very Low Hydration, V Kurkal, R M. Daniel, John L. Finney, Moeava Tehei, R V. Dunn, Jeremy C. Smith
Enzyme Activity And Flexibility At Very Low Hydration, V Kurkal, R M. Daniel, John L. Finney, Moeava Tehei, R V. Dunn, Jeremy C. Smith
Faculty of Science, Medicine and Health - Papers: part A
Recent measurements have demonstrated enzyme activity at hydrations as low as 3%. This raises the question of whether hydration-induced enzyme flexibility is important for activity. Here, to address this, picosecond dynamic neutron scattering experiments are performed on pig liver esterase powders at 0%, 3%, 12%, and 50% hydration by weight and at temperatures ranging from 120 to 300 K. At all temperatures and hydrations, significant quasielastic scattering intensity is found in the protein, indicating the presence of anharmonic, diffusive motion. As the hydration increases, a temperature-dependent dynamical transition appears and strengthens involving additional diffusive motion. The implication of these results …
Replication Termination In Escherichia Coli: Structure And Anti-Helicase Activity Of The Tus-Ter Complex, Cameron Neylon, Andrew V. Kralicek, Thomas M. Hill, Nicholas E. Dixon
Replication Termination In Escherichia Coli: Structure And Anti-Helicase Activity Of The Tus-Ter Complex, Cameron Neylon, Andrew V. Kralicek, Thomas M. Hill, Nicholas E. Dixon
Faculty of Science, Medicine and Health - Papers: part A
The arrest of DNA replication in Escherichia coli is triggered by the encounter of a replisome with a Tus protein-Ter DNA complex. A replication fork can pass through a Tus-Ter complex when traveling in one direction but not the other, and the chromosomal Ter sites are oriented so replication forks can enter, but not exit, the terminus region. The Tus-Ter complex acts by blocking the action of the replicative DnaB helicase, but details of the mechanism are uncertain. One proposed mechanism involves a specific interaction between Tus-Ter and the helicase that prevents further DNA unwinding, while …
Immune Responses Of A Liposome/Iscom Vaccine Adjuvant Against Streptococcal Fibronectin Binding Protein 1 (Sfb1) In Mice, Jason D. Mcarthur, K Schulze, James Chin, B J. Currie, K S. Sriprakash, S R. Talay, G S. Chhatwal, C A. Guzman, Mark J. Walker
Immune Responses Of A Liposome/Iscom Vaccine Adjuvant Against Streptococcal Fibronectin Binding Protein 1 (Sfb1) In Mice, Jason D. Mcarthur, K Schulze, James Chin, B J. Currie, K S. Sriprakash, S R. Talay, G S. Chhatwal, C A. Guzman, Mark J. Walker
Faculty of Science, Medicine and Health - Papers: part A
BACKGROUND & OBJECTIVES: The fibronectin binding protein Sfb1 of Streptococcus pyogenes is a well characterised antigen which induces protection against lethal challenge with group A streptococcus (GAS) when adjuvanted with cholera toxin B-subunit (CTB). As an alternative to CTB adjuvanted intranasal immunisations we investigated the immune responses generated in mice using Sfb1 incorporated in to the skin and mucosal adjuvant SAMA4. METHODS: Mice (BALB/c) were vaccinated intradermally with 100 microl of either SAMA4 (adjuvant only group) or SAMA4/Sfb1 and were boosted 7 days later. Mice vaccinated with CTB based vaccines were immunised by intranasal inoculation with a mixture containing 30 …
Cell Surface Antigens Of Mycoplasma Species Bovine Group 7 Bind And Activate Plasminogen, Kylie Bower, Steven Djordjevic, Nicholas M Andronicos, Marie Ranson
Cell Surface Antigens Of Mycoplasma Species Bovine Group 7 Bind And Activate Plasminogen, Kylie Bower, Steven Djordjevic, Nicholas M Andronicos, Marie Ranson
Faculty of Science, Medicine and Health - Papers: part A
Mycoplasma species bovine group 7 bound plasminogen at the cell surface in a lysine-dependent manner. Cell-bound plasminogen was rapidly activated to plasmin by exogenous urokinase, and this activity was associated with plasminogen binding capacity. Binding assays using plasminogen modified with a trifunctional cross-linking agent revealed several binding proteins.
Flexibility Revealed By The 1.85 Å Crystal Structure Of The Β Sliding-Clamp Subunit Of Escherichia Coli Dna Polymerase Iii, Aaron J. Oakley, Pavel Prosselkov, Gene Wijffels, Jennifer L. Beck, Matthew Cj Wilce, Nicholas E. Dixon
Flexibility Revealed By The 1.85 Å Crystal Structure Of The Β Sliding-Clamp Subunit Of Escherichia Coli Dna Polymerase Iii, Aaron J. Oakley, Pavel Prosselkov, Gene Wijffels, Jennifer L. Beck, Matthew Cj Wilce, Nicholas E. Dixon
Faculty of Science, Medicine and Health - Papers: part A
The subunit of the Escherichia coli replicative DNA polymerase III holoenzyme is the sliding clamp that interacts with the (polymerase) subunit to maintain the high processivity of the enzyme. The protein is a ring-shaped dimer of 40.6 kDa subunits whose structure has previously been determined at a resolution of 2.5 Å [Kong et al. (1992), Cell, 69, 425-437]. Here, the construction of a new plasmid that directs overproduction of to very high levels and a simple procedure for large-scale purification of the protein are described. Crystals grown under slightly modified conditions diffracted to beyond 1.9 Å at 100 …
Distribution Of Intimin Subtypes Among Escherichia Coli Isolates From Ruminant And Human Sources, Vidiya Ramachandran, Kim Brett, Michael A Hornitzky, Mark Dowton, Karl A Bettelheim, Mark J. Walker, Steven P. Djordjevic
Distribution Of Intimin Subtypes Among Escherichia Coli Isolates From Ruminant And Human Sources, Vidiya Ramachandran, Kim Brett, Michael A Hornitzky, Mark Dowton, Karl A Bettelheim, Mark J. Walker, Steven P. Djordjevic
Faculty of Science, Medicine and Health - Papers: part A
The intimin gene eae, located within the locus of enterocyte effacement pathogenicity island, distinguishes enteropathogenic Escherichia coli (EPEC) and some Shiga toxin-producing E. coli (STEC) strains from all other pathotypes of diarrheagenic E. coli. EPEC is a leading cause of infantile diarrhea in developing countries, and intimin-positive STEC isolates are typically associated with life-threatening diseases such as hemolytic-uremic syndrome and hemorrhagic colitis. Here we describe the development of a PCR-restriction fragment length polymorphism (RFLP) assay that reliably differentiates all 11 known intimin types (α1, α2, β, γ, κ, ɛ, η, ι, λ, θ, and ζ) and three new …
Initial Studies On Alkaloids From Lombok Medicinal Plants, Surya Hadi, John B. Bremner
Initial Studies On Alkaloids From Lombok Medicinal Plants, Surya Hadi, John B. Bremner
Faculty of Science, Medicine and Health - Papers: part A
Initial investigation of medicinal plants from Lombok has resulted in the collection of 100 plant species predicted to have antimicrobial, including antimalarial, properties according to local medicinal uses. These plants represent 49 families and 80 genera; 23% of the plants tested positively for alkaloids. Among the plants testing positive, five have been selected for further investigation involving structure elucidation and antimicrobial testing on the extracted alkaloids. Initial work on structural elucidation of some of the alkaloids is reported briefly.
Indole Derivatives From The Egg Masses Of Muricid Molluscs, Kirsten Benkendorff, John B. Bremner, Andrew R. Davis
Indole Derivatives From The Egg Masses Of Muricid Molluscs, Kirsten Benkendorff, John B. Bremner, Andrew R. Davis
Faculty of Science, Medicine and Health - Papers: part A
A range of brominated indole derivatives were found in the egg masses of six species of muricid molluscs. Several non-brominated indoles were also present in the eggs of two Mediterranean Muricidae, although these were not found in the Australian species. Tyrindoleninone (3), was the only compound found in all six species and is likely to be responsible for the observed antimicrobial activity of these muricid egg masses [1,2]. These bioactive indoles appear to be characteristic of muricid egg masses and were not found in the egg masses from 17 species in different families of marine molluscs.
Single Nucleotide Primer Extension (Snupe) Analysis Of The G6pd Gene In Somatic Cells And Oocytes Of A Kangaroo (Macropus Robustus), Debbie Watson, Anita S. Jacombs, David A. Loebel, Edward S. Robinson, Peter G. Johnston
Single Nucleotide Primer Extension (Snupe) Analysis Of The G6pd Gene In Somatic Cells And Oocytes Of A Kangaroo (Macropus Robustus), Debbie Watson, Anita S. Jacombs, David A. Loebel, Edward S. Robinson, Peter G. Johnston
Faculty of Science, Medicine and Health - Papers: part A
cDNA sequence analysis of the X-linked glucose-6-phosphate dehydrogenase (G6PD) gene has shown a base difference between two subspecies of the kangaroo, Macropus robustus robustus (wallaroo) and M. r. erubescens (euro). A thymine residue in the wallaroo at position 358 in exon 5 has been replaced by a cytosine residue in the euro, which accounts for the previously reported electrophoretic difference between the two subspecies. This base difference allowed use of the Single Nucleotide Primer Extension (SNuPE) technique to study allele-specific expression of G6PD at the transcriptional level. We began by examining G6PD expression in somatic cells and observed complete paternal …
Role Of Phosphoglucomutase Of Bordetella Bronchiseptica In Lipopolysaccharide Biosynthesis And Virulence, Nicholas P. West, Heidrun Jungnitz, John Fitter, Jason D. Mcarthur, Carlos Guzman, Mark J. Walker
Role Of Phosphoglucomutase Of Bordetella Bronchiseptica In Lipopolysaccharide Biosynthesis And Virulence, Nicholas P. West, Heidrun Jungnitz, John Fitter, Jason D. Mcarthur, Carlos Guzman, Mark J. Walker
Faculty of Science, Medicine and Health - Papers: part A
The phosphoglucomutase (PGM)-encoding gene of Bordetella bronchiseptica is required for lipopolysaccharide (LPS) biosynthesis. An insertion mutant of the wild-type B. bronchiseptica strain BB7865 which disrupted LPS biosynthesis was created and characterized (BB7865pgm). Genetic analysis of the mutated gene showed it shares high identity with PGM genes of various bacterial species and forms part of an operon which also encompasses the gene encoding phosphoglucose isomerase. Functional assays for PGM revealed that enzyme activity is expressed in bothbvg-positive and bvg-negative strains ofB. bronchiseptica and is substantially reduced in BB7865pgm. Complementation of the mutated PGM …
Clusterin Protein Diversity In The Primate Eye, Paul Wong, Bruce A. Pfeffer, Steven L. Bernstein, Michelle L. Chambers, Gerald J. Chader, Zahra F. Zakeri, Yan-Q Wu, Mark Wilson, S Patricia Becerra
Clusterin Protein Diversity In The Primate Eye, Paul Wong, Bruce A. Pfeffer, Steven L. Bernstein, Michelle L. Chambers, Gerald J. Chader, Zahra F. Zakeri, Yan-Q Wu, Mark Wilson, S Patricia Becerra
Faculty of Science, Medicine and Health - Papers: part A
Purpose: The clusterin gene encodes a multi-functional protein that has been identified in different tissues, including a number of different eye tissues, primarily in the mouse and to a much lesser extent in humans. Clusterin has been implicated in a number of cellular processes such as lipid transport, membrane integrity, apoptosis, and neurodegeneration, all of which could be important to the biology of the eye. In the current communication, we provide data that confirms the expression of clusterin in a number of different human eye tissues and establishes the expression profile of this gene in monkey derived eye tissues. The …