1ssx: Difference between revisions
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'''0.83A resolution crystal structure of alpha-lytic protease at pH 8''' | {{Structure | ||
|PDB= 1ssx |SIZE=350|CAPTION= <scene name='initialview01'>1ssx</scene>, resolution 0.83Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene> and <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Alpha-lytic_endopeptidase Alpha-lytic endopeptidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.12 3.4.21.12] | |||
|GENE= ALPHA-LP ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=69 Lysobacter enzymogenes]) | |||
}} | |||
'''0.83A resolution crystal structure of alpha-lytic protease at pH 8''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
1SSX is a [ | 1SSX is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Lysobacter_enzymogenes Lysobacter enzymogenes]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SSX OCA]. | ||
==Reference== | ==Reference== | ||
The 0.83 A resolution crystal structure of alpha-lytic protease reveals the detailed structure of the active site and identifies a source of conformational strain., Fuhrmann CN, Kelch BA, Ota N, Agard DA, J Mol Biol. 2004 May 14;338(5):999-1013. PMID:[http:// | The 0.83 A resolution crystal structure of alpha-lytic protease reveals the detailed structure of the active site and identifies a source of conformational strain., Fuhrmann CN, Kelch BA, Ota N, Agard DA, J Mol Biol. 2004 May 14;338(5):999-1013. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15111063 15111063] | ||
[[Category: Alpha-lytic endopeptidase]] | [[Category: Alpha-lytic endopeptidase]] | ||
[[Category: Lysobacter enzymogenes]] | [[Category: Lysobacter enzymogenes]] | ||
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[[Category: ultra-high resolution]] | [[Category: ultra-high resolution]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 14:09:18 2008'' | ||
Revision as of 15:09, 20 March 2008
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| , resolution 0.83Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Gene: | ALPHA-LP (Lysobacter enzymogenes) | ||||||
| Activity: | Alpha-lytic endopeptidase, with EC number 3.4.21.12 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
0.83A resolution crystal structure of alpha-lytic protease at pH 8
OverviewOverview
The crystal structure of the extracellular bacterial serine protease alpha-lytic protease (alphaLP) has been solved at 0.83 A resolution at pH 8. This ultra-high resolution structure allows accurate analysis of structural elements not possible with previous structures. Hydrogen atoms are visible, and confirm active-site hydrogen-bonding interactions expected for the apo enzyme. In particular, His57 N(delta1) participates in a normal hydrogen bond with Asp102 in the catalytic triad, with a hydrogen atom visible 0.83(+/-0.06)A from the His N(delta1). The catalytic Ser195 occupies two conformations, one corresponding to a population of His57 that is doubly protonated, the other to the singly protonated His57. Based on the occupancy of these conformations, the pKa of His57 is calculated to be approximately 8.8 when a sulfate ion occupies the active site. This 0.83 A structure has allowed critical analysis of geometric distortions within the structure. Interestingly, Phe228 is significantly distorted from planarity. The distortion of Phe228, buried in the core of the C-terminal domain, occurs at an estimated energetic cost of 4.1 kcal/mol. The conformational space for Phe228 is severely limited by the presence of Trp199, which prevents Phe228 from adopting the rotamer observed in many other chymotrypsin family members. In alphaLP, the only allowed rotamer leads to the deformation of Phe228 due to steric interactions with Thr181. We hypothesize that tight packing of co-evolved residues in this region, and the subsequent deformation of Phe228, contributes to the high cooperativity and large energetic barriers for folding and unfolding of alphaLP. The kinetic stability imparted by the large, cooperative unfolding barrier plays a critical role in extending the lifetime of the protease in its harsh environment.
About this StructureAbout this Structure
1SSX is a Single protein structure of sequence from Lysobacter enzymogenes. Full crystallographic information is available from OCA.
ReferenceReference
The 0.83 A resolution crystal structure of alpha-lytic protease reveals the detailed structure of the active site and identifies a source of conformational strain., Fuhrmann CN, Kelch BA, Ota N, Agard DA, J Mol Biol. 2004 May 14;338(5):999-1013. PMID:15111063
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