Effect of Organic Solvents on the Molten Globule State of Procerain: β-Sheet to α-Helix Switchover in Presence of Trifluoroethanol

Author(s): Vikash K. Dubey, Ashu Shah, Medicherla V. Jagannadham, Arvind M. Kayastha.

Journal Name: Protein & Peptide Letters

Volume 13 , Issue 6 , 2006

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The effect of methanol and trifluoroethanol (TFE) on the structure and folding of molten globule state of procerain, a cysteine protease from Calotropis procera, was studied by circular dichroism spectroscopy. The magnitude of ellipticity at 215 nm, as a measure of β-sheet content, is dependent on the concentration of the TFE. Interestingly, a switch over from the β-sheet structure of the molten globule state to α-helix was observed at 60% TFE and the ellipticity at 222 nm increased as a function of TFE concentration beyond this critical TFE concentration. Temperature induced unfolding of the molten globule state of procerain in 10% methanol showed stabilization of α-rich domain with concomitant destabilization of β-rich domain. Using higher concentration of methanol (20-40 %) had no stabilizing effect on the α-rich domain however, the β-rich domain was destabilized, indicating that the stability of the domains were not interdependent and that a low concentration of methanol induced stabilization in α-rich domain.

Keywords: Plant cysteine protease, procerain, physiochemical studies, domain stability

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Article Details

Year: 2006
Page: [545 - 547]
Pages: 3
DOI: 10.2174/092986606777145823
Price: $58

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