Engineering a Hyper-catalytic Enzyme by Photoactivated Conformation Modulation
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- 作者：Pratul K. Agarwal ; Christopher Schultz ; Aristotle Kalivretenos ; Brahma Ghosh ; Sheldon E. Broedel ; Jr.
- 刊名：The Journal of Physical Chemistry Letters
- 出版年：2012
- 出版时间：May 3, 2012
- 年：2012
- 卷：3
- 期：9
- 页码：1142-1146
- 全文大小：274K
- 年卷期：v.3,no.9(May 3, 2012)
- ISSN：1948-7185
文摘
Enzyme engineering for improved catalysis has wide implications. We describe a novel chemical modification of Candida antarctica lipase B that allows modulation of the enzyme conformation to promote catalysis. Computational modeling was used to identify dynamical enzyme regions that impact the catalytic mechanism. Surface loop regions located distal to active site but showing dynamical coupling to the reaction were connected by a chemical bridge between Lys136 and Pro192, containing a derivative of azobenzene. The conformational modulation of the enzyme was achieved using two sources of light that alternated the azobenzene moiety in cis and trans conformations. Computational model predicted that mechanical energy from the conformational fluctuations facilitate the reaction in the active-site. The results were consistent with predictions as the activity of the engineered enzyme was found to be enhanced with photoactivation. Preliminary estimations indicate that the engineered enzyme achieved 8鈥?2 fold better catalytic activity than the unmodulated enzyme.