1nli
From Proteopedia
(New page: 200px<br /><applet load="1nli" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nli, resolution 1.93Å" /> '''Complex of [E160A-E1...) |
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| - | [[Image:1nli.jpg|left|200px]]<br /><applet load="1nli" size=" | + | [[Image:1nli.jpg|left|200px]]<br /><applet load="1nli" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1nli, resolution 1.93Å" /> | caption="1nli, resolution 1.93Å" /> | ||
'''Complex of [E160A-E189A] trichosanthin and adenine'''<br /> | '''Complex of [E160A-E189A] trichosanthin and adenine'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Trichosanthin is a ribosome-inactivating protein that cleaves specifically | + | Trichosanthin is a ribosome-inactivating protein that cleaves specifically the N-glycosidic bond of A-4324 of 28S rRNA. Trichosanthin and its variant [E160A-E189A]-trichosanthin were found to bind an adenine base with a K(d) value of approximately 0.2mM. To determine how this doubly mutated variant of trichosanthin interacts with adenine, the co-crystal structure of [E160A-E189A]-trichosanthin and adenine was resolved to 0.193nm which revealed that the active site conformation of the doubly mutated variant is isomorphous to wild-type trichosanthin. Water molecules were found at locations corresponding to the eliminated side chain of Glu-160 and Glu-189. On the other hand, the adenine base interacted with [E160A-E189A]-trichosanthin in a manner similar to that in wild-type trichosanthin. Our structural analysis illustrates that Glu-160 and Glu-189 in trichosanthin do not play an important role in maintaining the active site conformation and binding adenine, an essential step for substrate-enzyme interaction. On the other hand, removal of two glutamate residues changed a large patch of negatively charged surface to a positive charge, which may account for the destabilization of the oxocarbenium-like transition-state and the significant decrease in ribosome-inactivating activity in [E160A-E189A]-trichosanthin. |
==About this Structure== | ==About this Structure== | ||
| - | 1NLI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Trichosanthes_kirilowii Trichosanthes kirilowii] with ADE as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/rRNA_N-glycosylase rRNA N-glycosylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.22 3.2.2.22] Full crystallographic information is available from [http:// | + | 1NLI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Trichosanthes_kirilowii Trichosanthes kirilowii] with <scene name='pdbligand=ADE:'>ADE</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/rRNA_N-glycosylase rRNA N-glycosylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.22 3.2.2.22] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NLI OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Trichosanthes kirilowii]] | [[Category: Trichosanthes kirilowii]] | ||
[[Category: rRNA N-glycosylase]] | [[Category: rRNA N-glycosylase]] | ||
| - | [[Category: Chan, D | + | [[Category: Chan, D S.B.]] |
| - | [[Category: Shaw, P | + | [[Category: Shaw, P C.]] |
| - | [[Category: Williams, R | + | [[Category: Williams, R L.]] |
| - | [[Category: Wong, K | + | [[Category: Wong, K B.]] |
[[Category: ADE]] | [[Category: ADE]] | ||
[[Category: protein-dna complex]] | [[Category: protein-dna complex]] | ||
[[Category: ribosome-inactivating protein]] | [[Category: ribosome-inactivating protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:07:20 2008'' |
Revision as of 12:07, 21 February 2008
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Complex of [E160A-E189A] trichosanthin and adenine
Overview
Trichosanthin is a ribosome-inactivating protein that cleaves specifically the N-glycosidic bond of A-4324 of 28S rRNA. Trichosanthin and its variant [E160A-E189A]-trichosanthin were found to bind an adenine base with a K(d) value of approximately 0.2mM. To determine how this doubly mutated variant of trichosanthin interacts with adenine, the co-crystal structure of [E160A-E189A]-trichosanthin and adenine was resolved to 0.193nm which revealed that the active site conformation of the doubly mutated variant is isomorphous to wild-type trichosanthin. Water molecules were found at locations corresponding to the eliminated side chain of Glu-160 and Glu-189. On the other hand, the adenine base interacted with [E160A-E189A]-trichosanthin in a manner similar to that in wild-type trichosanthin. Our structural analysis illustrates that Glu-160 and Glu-189 in trichosanthin do not play an important role in maintaining the active site conformation and binding adenine, an essential step for substrate-enzyme interaction. On the other hand, removal of two glutamate residues changed a large patch of negatively charged surface to a positive charge, which may account for the destabilization of the oxocarbenium-like transition-state and the significant decrease in ribosome-inactivating activity in [E160A-E189A]-trichosanthin.
About this Structure
1NLI is a Single protein structure of sequence from Trichosanthes kirilowii with as ligand. Active as rRNA N-glycosylase, with EC number 3.2.2.22 Full crystallographic information is available from OCA.
Reference
Structural basis for the interaction of [E160A-E189A]-trichosanthin with adenine., Shaw PC, Wong KB, Chan DS, Williams RL, Toxicon. 2003 Apr;41(5):575-81. PMID:12676436
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