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Sandbox 39
From Proteopedia
(Difference between revisions)
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{{Template: Oberholser Sandbox Reservation}} | {{Template: Oberholser Sandbox Reservation}} | ||
| - | <StructureSection load='9pap' size=' | + | <StructureSection load='9pap' size='300' side='right' caption='Structure of Papain(PDB entry [[9pap]])' scene=''> |
=='''Papain'''== | =='''Papain'''== | ||
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== Function == | == Function == | ||
| - | As a cysteine protease, Papain utilizes a nucleophilic cysteine thiol as part of its catalytic triad. | + | As a cysteine protease, Papain utilizes a nucleophilic cysteine thiol as part of its catalytic triad. Papain's Cys-25 is deprotonated by its His-159. The now nucleophilic Cys-25 attacks the carbonyl carbon of the peptide backbone, forming an acyl enzyme intermediate in which the peptide's amino terminal is free. Also in this step, His-159 is returned to its deprotonated form. The intermediate is then deacylated by a water molecule, and it releases the carboxyl terminal of the peptide to produce the product and regenerate the active enzyme. This entire mechanism is shown below: |
[[Image:jrip.jpg]] | [[Image:jrip.jpg]] | ||
Revision as of 23:14, 8 November 2011
| Please do NOT make changes to this Sandbox. Sandboxes 30-60 are reserved for use by Biochemistry 410 & 412 at Messiah College taught by Dr. Hannah Tims during Fall 2012 and Spring 2013. |
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