We apologize for Proteopedia being slow to respond. For the past two years, a new implementation of Proteopedia has been being built. Soon, it will replace this 18-year old system. All existing content will be moved to the new system at a date that will be announced here.

1xlu

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1xlu.gif|left|200px]]
+
{{Seed}}
 +
[[Image:1xlu.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1xlu| PDB=1xlu | SCENE= }}
{{STRUCTURE_1xlu| PDB=1xlu | SCENE= }}
-
'''X-Ray Structure Of Di-Isopropyl-Phosphoro-Fluoridate (Dfp) Inhibited Butyrylcholinesterase after Aging'''
+
===X-Ray Structure Of Di-Isopropyl-Phosphoro-Fluoridate (Dfp) Inhibited Butyrylcholinesterase after Aging===
-
==Overview==
+
<!--
-
Organophosphorus poisons (OP) bind covalently to the active-site serine of cholinesterases. The inhibited enzyme can usually be reactivated with powerful nucleophiles such as oximes. However, the covalently bound OP can undergo a suicide reaction (termed aging) yielding nonreactivatable enzyme. In human butyrylcholinesterase (hBChE), aging involves the residues His438 and Glu197 that are proximal to the active-site serine (Ser198). The mechanism of aging is known in detail for the nerve gases soman, sarin, and tabun as well as the pesticide metabolite isomalathion. Aging of soman- and sarin-inhibited acetylcholinesterase occurs by C-O bond cleavage, whereas that of tabun- and isomalathion-inhibited acetylcholinesterase occurs by P-N and P-S bond cleavage, respectively. In this work, the crystal structures of hBChE inhibited by the ophthalmic reagents echothiophate (nonaged and aged) and diisopropylfluorophosphate (aged) were solved and refined to 2.1, 2.25, and 2.2 A resolution, respectively. No appreciable shift in the position of the catalytic triad histidine was observed between the aged and nonaged conjugates of hBChE. This absence of shift contrasts with the aged and nonaged crystal structures of Torpedo californica acetylcholinesterase inhibited by the nerve agent VX. The nonaged hBChE structure shows one water molecule interacting with Glu197 and the catalytic triad histidine (His438). Interestingly, this water molecule is ideally positioned to promote aging by two mechanisms: breaking either a C-O bond or a P-O bond. Pesticides and certain stereoisomers of nerve agents are expected to undergo aging by breaking the P-O bond.
+
The line below this paragraph, {{ABSTRACT_PUBMED_15667209}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 15667209 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_15667209}}
==About this Structure==
==About this Structure==
Line 29: Line 33:
[[Category: Nachon, F.]]
[[Category: Nachon, F.]]
[[Category: Cholinesterase]]
[[Category: Cholinesterase]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 15:11:40 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 07:38:37 2008''

Revision as of 04:38, 28 July 2008

Image:1xlu.png

Template:STRUCTURE 1xlu

X-Ray Structure Of Di-Isopropyl-Phosphoro-Fluoridate (Dfp) Inhibited Butyrylcholinesterase after Aging

Template:ABSTRACT PUBMED 15667209

About this Structure

1XLU is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.

Reference

Role of water in aging of human butyrylcholinesterase inhibited by echothiophate: the crystal structure suggests two alternative mechanisms of aging., Nachon F, Asojo OA, Borgstahl GE, Masson P, Lockridge O, Biochemistry. 2005 Feb 1;44(4):1154-62. PMID:15667209

Page seeded by OCA on Mon Jul 28 07:38:37 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1xlu"
Personal tools