1f9c
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1f9c.jpg|left|200px]] | [[Image:1f9c.jpg|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1f9c", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | | | + | --> |
| - | | | + | {{STRUCTURE_1f9c| PDB=1f9c | SCENE= }} |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''CRYSTAL STRUCTURE OF MLE D178N VARIANT''' | '''CRYSTAL STRUCTURE OF MLE D178N VARIANT''' | ||
| Line 30: | Line 27: | ||
[[Category: Kajander, T.]] | [[Category: Kajander, T.]] | ||
[[Category: Lehtio, L.]] | [[Category: Lehtio, L.]] | ||
| - | [[Category: | + | [[Category: Thermostable mutant]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 16:03:48 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 13:03, 2 May 2008
CRYSTAL STRUCTURE OF MLE D178N VARIANT
Overview
BACKGROUND: The traditional picture of charged amino acids in globular proteins is that they are almost exclusively on the outside exposed to the solvent. Buried charges, when they do occur, are assumed to play an essential role in catalysis and ligand binding, or in stabilizing structure as, for instance, helix caps. RESULTS: By analyzing the amount and distribution of buried charged surface and charges in proteins over a broad range of protein sizes, we show that buried charge is much more common than is generally believed. We also show that the amount of buried charge rises with protein size in a manner which differs from other types of surfaces, especially aromatic and polar uncharged surfaces. In large proteins such as hemocyanin, 35% of all charges are greater than 75% buried. Furthermore, at all sizes few charged groups are fully exposed. As an experimental test, we show that replacement of the buried D178 of muconate lactonizing enzyme by N stabilizes the enzyme by 4.2 degrees C without any change in crystallographic structure. In addition, free energy calculations of stability support the experimental results. CONCLUSIONS: Nature may use charge burial to reduce protein stability; not all buried charges are fully stabilized by a prearranged protein environment. Consistent with this view, thermophilic proteins often have less buried charge. Modifying the amount of buried charge at carefully chosen sites may thus provide a general route for changing the thermophilicity or psychrophilicity of proteins.
About this Structure
1F9C is a Single protein structure of sequence from Pseudomonas putida. Full crystallographic information is available from OCA.
Reference
Buried charged surface in proteins., Kajander T, Kahn PC, Passila SH, Cohen DC, Lehtio L, Adolfsen W, Warwicker J, Schell U, Goldman A, Structure. 2000 Nov 15;8(11):1203-14. PMID:11080642 Page seeded by OCA on Fri May 2 16:03:48 2008
