TAILIEUCHUNG - Báo cáo Y học: A Raman optical activity study of rheomorphism in caseins, synucleins and tau New insight into the structure and behaviour of natively unfolded proteins

The casein milk proteins and the brain proteinsa-synuclein and tau have been described as natively unfolded with ran-domcoil structures,which, inthecaseofa-synucleinandtau, have a propensity to form the ®brils found in a number of neurodegenerative diseases. New insight into the structures of these proteins has been provided by a Raman optical activity study, supplemented with di erential scanning cal-orimetry, of bovineb-andj-casein, recombinant humana-, b-andc-synuclein, | Eur. J. Biochem. 269 148-156 2002 FEBS 2002 A Raman optical activity study of rheomorphism in caseins synucleins and tau New insight into the structure and behaviour of natively unfolded proteins Christopher D. Syme1 Ewan W. Blanch1 Carl Holt2 Ross Jakes3 Michel Goedert3 Lutz Hecht1 and Laurence D. Barron1 1 Department of Chemistry University of Glasgow UK 2Hannah Research Institute Ayr UK 3Medical Research Council Laboratory of Molecular Biology Cambridge UK The casein milk proteins and the brain proteins a-synuclein and tau have been described as natively unfolded with random coil structures which in the case of a-synuclein and tau have a propensity to form the fibrils found in a number of neurodegenerative diseases. New insight into the structures of these proteins has been provided by a Raman optical activity study supplemented with differential scanning calorimetry of bovine p- and K-casein recombinant human a- P- and y-synuclein together with the A30P and A53T mutants of a-synuclein associated with familial cases of Parkinson s disease and recombinant human tau46 together with the tau46 P301L mutant associated with inherited frontotemporal dementia. The Raman optical activity spectra of all these proteins are very similar being dominated by a strong positive band centred at 1318 cm 1 that may be due to the poly L-proline II PPII helical conformation. There are no Raman optical activity bands characteristic of extended secondary structure although some unassociated P strand may be present. Differential scanning calorimetry revealed no thermal transitions for these proteins in the range 15-110 C suggesting that the structures are loose and noncooperative. As it is extended flexible lacks intrachain hydrogen bonds and is hydrated in aqueous solution PPII helix may impart a rheomorphic flowing shape character to the structure of these proteins that could be essential for their native function but which may in the case of a-synuclein and tau result in a propensity

• Báo cáo khoa học
• Report medicine
• traditional medicine
• scientific reports
• Structural biochemistry
• oxidation
• bacteria
• medical knowledge
• medical research
• analysis of cytoplasmic
• Crystal structure
• hemoglobin
• medicine
• cell proliferation
• breast cancer
• chemical reaction
• gastric cancer
• hormone medicine
• tumor cells
• biochemical studies
• environmental medicine