Characterisation of amyloid fibrils formed from beta ...

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Research Colworth, Colworth House, Sharnbrook, Bedford MK44. tLQ, UK. 'Protein-misfolding diseases' are ... and Brian Austen. Neurodegeneration Unit, St ...
Biochemical Society Transactions (2002) Volume 30, Part 3



Characterisation of amyloid fibrils formed from p-lactoglobulin. Walrai S. Goyla, Simon B. Ross-Murphya, Paul D. A. Pudney ,Allan H. Clarkb.


aDivision of Life Sciences, King’s College London, Franklin- Wilkins Building, 150 Stamford Street, London SE1 9NN, UK. bUnilever Research Colworth, Colworth House, Sharnbrook, Bedford MK44 t L Q , UK.

Institute of Pharmacy, University of Sunderland, Sunderland, SR2 3SD; School of Pharmacy, University of Bradford, Bradford, BD7 1DP

’Protein-misfolding diseases’ are characterised by abnormal protein deposits often composed of linear aggregates termed amyloid fibrils. Engineering conditions whereby proteins and peptides that are not associated with disease, self-assemble, may provide an insight to mechanisms of fibrillisation. In this study we monitored fibril formation of p-lactoglobulin by the use of various techniques, whose scope spans several distance lengths. Fibrils were formed under various conditions, in particular under thermal and alcohol-mediated unfolding. The conditions employed largely governed the morphology of fibrils as is evident from atomic-force & electron microscopy. Raman & FTIR spectroscopy confirms a near native structure, with a slight increase in the amount of p-sheet, regardless of fibril morphology. The resulting gels formed from the two processes have also been studied by mechanical spectroscopy, which provided some interesting insights into fibril network properties. Here, the kinetics of the gel cure-curve with parameters such as the modulus at infinite time and the critical sol-gel transition time are currently being rationalised by various network models, which encompass the network branching probability, and the kinetics of assembly.

Changes in Nestin and AMPA receptors are associated with preconditioning of the mouse cortex by repetitive spreading depression P.L. Chazot, O.V. Godukhin, T.P. Obrenovitch

Cortical Spreading Depression (CSD) is a robust method for the induction of brain preconditioning, i.e., adaptative cytoprotection that protects against subsequent, potentially lethal insults. Ten consecutive CSD were elicited by epidural application of 1M KCI to the occipital region in halothane anaesthetized mice. Each CSD propagated throughout the whole hemicortex [I]. In sham-operated controls, 1M KCI was replaced by physiological saline. Individual whole hemicortices (n = 4 for each group) were dissected out 24h post-treatment, P2 membranes prepared and subjected t o quantitative immunoblotting, with p-actin standardization [2]. In comparison t o the sham-treated group, KCI-treatment markedly INCREASED nestin immunoreactivity (3.4 +/- 0.9-fold; p

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