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Sandbox 46
From Proteopedia
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<applet load='1QLQ' size='300' frame='true' align='right' caption='Trypsin' /> | <applet load='1QLQ' size='300' frame='true' align='right' caption='Trypsin' /> | ||
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=Trypsin= | =Trypsin= | ||
Trypsin, a member of the serine protease family, is produced in the pancreas and found in the digestive tracks of vertebrates. To avoid pancreatic self-degradation, trypsin is synthesized as trypsinogen, a zymogen. Cleavage by enteropeptidase allows tryspin to enter its active form. As a serine protease, trypsin contains a serine residue in its active site. | Trypsin, a member of the serine protease family, is produced in the pancreas and found in the digestive tracks of vertebrates. To avoid pancreatic self-degradation, trypsin is synthesized as trypsinogen, a zymogen. Cleavage by enteropeptidase allows tryspin to enter its active form. As a serine protease, trypsin contains a serine residue in its active site. | ||
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==Structure== | ==Structure== | ||
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| - | The <scene name='Sandbox_46/Tryp_secondary_color/2'>secondary structure</scene> of Trypsin consists of two alpha helices (light green) and two beta sheets (peach). | + | The <scene name='Sandbox_46/Tryp_secondary_color/2'>secondary structure</scene> of Trypsin consists of two alpha helices (light green) and two beta sheets (peach). |
| + | Hydrophobic interactions - mainly the hydrophobic collapse - significantly contribute to both secondary and tertiary structure. This <scene name='Sandbox_46/Polar_vs_nonpolar_wire/1'>structure</scene> shows that the majority of the residues are non-polar/hydrophobic (maroon). These residues tend to congregate on the interior of the structure while polar/hydrophilic residues (blue) remain on the exterior. This orientation allows polar molecules to maximize interaction with water and other polar molecules while non-polar molecules minimize such interactions. Adding water molecules to the model, the <scene name='Sandbox_46/Polar_vs_nonpolar/1'>polar/non-polar</scene> interactions can be seen. | ||
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| - | <scene name='Sandbox_46/Polar_vs_nonpolar/1'>polar vs. nonpolar</scene> | ||
| - | <scene name='Sandbox_46/Polar_vs_nonpolar_wire/1'>Wire</scene> | ||
===Stability=== | ===Stability=== | ||
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<scene name='Sandbox_46/H_bonds_r_groups/1'>H bonds r groups</scene> | <scene name='Sandbox_46/H_bonds_r_groups/1'>H bonds r groups</scene> | ||
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| + | The yellow and red molecules represent SO4 (2-) moieties which are not part of the traditional trypsin structure; they were added during crystallization to freeze Trypsin in a specific conformation. '''Fix THIS. they bind at active site''' | ||
==Function== | ==Function== | ||
Revision as of 19:59, 29 October 2010
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Contents |
Trypsin
Trypsin, a member of the serine protease family, is produced in the pancreas and found in the digestive tracks of vertebrates. To avoid pancreatic self-degradation, trypsin is synthesized as trypsinogen, a zymogen. Cleavage by enteropeptidase allows tryspin to enter its active form. As a serine protease, trypsin contains a serine residue in its active site.
Structure
The trypsin structure displayed is a mutant form isolated from a bovine pancreas. It contains 58 amino acid residues as well as an altered binding loop. To follow the primary structure (amino acid sequence) of Trypsin, click Begin at the N-terminus (blue) and move toward the C-terminus (red).
The of Trypsin consists of two alpha helices (light green) and two beta sheets (peach). Hydrophobic interactions - mainly the hydrophobic collapse - significantly contribute to both secondary and tertiary structure. This shows that the majority of the residues are non-polar/hydrophobic (maroon). These residues tend to congregate on the interior of the structure while polar/hydrophilic residues (blue) remain on the exterior. This orientation allows polar molecules to maximize interaction with water and other polar molecules while non-polar molecules minimize such interactions. Adding water molecules to the model, the interactions can be seen.
Stability
The yellow and red molecules represent SO4 (2-) moieties which are not part of the traditional trypsin structure; they were added during crystallization to freeze Trypsin in a specific conformation. Fix THIS. they bind at active site
Function
The reaction catalysed by Enteropeptidase:
trypsinogen → trypsin + hexapeptide
Val--(Asp)4--Lys--Ile--Val~ (trypsinogen) → Val--(Asp)4--Lys (hexapeptide) + Ile--Val~ (trypsin)
Enteropeptidase cleaves after Lysine if the Lys is preceded by four Asp and not followed by a Pro. Source ^ "Enterokinase, light chain (P8070), Proteases, NEB". http://www.neb.com/nebecomm/products/productP8070.asp. Retrieved 2007-10-04.
Shared active site
