title: Addressing mechanism of fibrillization/aggregation and its prevention in presence of osmolytes: spectroscopic and calorimetric approach.
abstract: Understanding the mechanism of protein fibrillization/aggregation and its prevention is the basis of development of therapeutic strategies for amyloidosis. An attempt has been made to understand the nature of interactions of osmolytes L-proline, 4-hydroxy-L-proline, sarcosine and trimethylamine N-oxide with the different stages of fibrillization of hen egg-white lysozyme by using a combination of isothermal titration calorimetry, differential scanning calorimetry, fluorescence spectroscopy, and transmission electron microscopy. Based on thioflavin T fluorescence emission intensities and microscopic images, the nucleation, elongation, and saturation phases of fibrillization have been identified. Isothermal titration calorimetry and differential scanning calorimetry have enabled a quantitative analysis of the nature of interactions of these osmolytes with various conformational states of lysozyme at different stages of fibrillization/aggregation. It is concluded that interaction of the osmolytes with lysozyme fibrils at both the nucleation and elongation stages are important steps in the prevention of fibrillization/aggregation. Identification of the nature of interactions is a key step towards the discovery and synthesis of target oriented potential inhibitors of these associations. This study is a first report in which calorimetry has been used to address interaction of potential inihibitiors with the protein at different stages of fibrillization.
authors.affiliation: University of Mumbai & Department of Atomic Energy, Centre for Excellence in Basic Sciences, Santacruz (E), Mumbai, India.
authors.forename: Sinjan
authors.initials: S
authors.lastname: Choudhary
authors.affiliation: Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, India.
authors.forename: Nand
authors.initials: N
authors.lastname: Kishore
mesh_terms: D000682:Amyloid / Q000737:chemistry; D000818:Animals; D052160:Benzothiazoles; D002152:Calorimetry, Differential Scanning; D002645:Chickens; D007700:Kinetics; D009113:Muramidase / Q000737:chemistry*; D009994:Osmolar Concentration; D066329:Protein Aggregates; D013050:Spectrometry, Fluorescence; D013844:Thiazoles / Q000737:chemistry; D017186:Titrimetry
chemical_list: D000682:Amyloid; D052160:Benzothiazoles; D066329:Protein Aggregates; D013844:Thiazoles; C009462:thioflavin T; D009113:Muramidase