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Updated: Aug 25, 2026

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
Obtaining higher transesterification rates with subtilisin Carlsberg in nonaqueous media
Ipsita Roy1, Aparna Sharma, Munishwar N Gupta
1Chemistry Department, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India.
Abstract:
Three phase partitioning (protein precipitate obtained as an interfacial layer between lower aqueous and upper t-butanol phases, formed by the addition of ammonium sulphate and t-butanol to the aqueous solution of protein) followed by lyophilization in the presence of two-component excipient resulted in 400-480x increases in transesterification activity of lyophilized powders of subtilisin Carlsberg, depending on the solvent. The three phase partitioned enzyme, 'dried' by washing with butanol, gave 3-4x higher rates (depending on the solvent used) than the enzyme preparation dried by lyophilization in the presence of two-component excipient system.
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