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Title: Molecular Structures and Dynamics of the Stepwise Activation Mechanism of a Matrix Metalloproteinase Zymogen: Challenging the Cysteine Switch Dogma

Abstract

Activation of matrix metalloproteinase zymogen (pro-MMP) is a vital homeostatic process, yet its molecular basis remains unresolved. Using stopped-flow X-ray spectroscopy of the active site zinc ion, we determined the temporal sequence of pro-MMP-9 activation catalyzed by tissue kallikrein protease in milliseconds to several minutes. The identity of three intermediates seen by X-ray spectroscopy was corroborated by molecular dynamics simulations and quantum mechanics/molecular mechanics calculations. The cysteine-zinc interaction that maintains enzyme latency is disrupted via active-site proton transfers that mediate transient metal-protein coordination events and eventual binding of water. Unexpectedly, these events ensue as a direct result of complexation of pro-MMP-9 and kallikrein and occur before proteolysis and eventual dissociation of the pro-peptide from the catalytic site. Here we demonstrate the synergism among long-range protein conformational transitions, local structural rearrangements, and fine atomic events in the process of zymogen activation.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
959763
Report Number(s):
BNL-82749-2009-JA
Journal ID: ISSN 0002-7863; JACSAT; TRN: US1005803
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Chemical Society; Journal Volume: 129
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 62 RADIOLOGY AND NUCLEAR MEDICINE; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 74 ATOMIC AND MOLECULAR PHYSICS; CYSTEINE; DISSOCIATION; ENZYMES; KALLIKREIN; MOLECULAR STRUCTURE; PROTEINS; PROTEOLYSIS; PROTONS; SYNERGISM; TRANSIENTS; WATER; X-RAY SPECTROSCOPY; ZINC IONS; national synchrotron light source

Citation Formats

Rosenblum,G., Meroueh, S., Toth, M., Fisher, J., Fridman, R., Mobashery, S., and Sagi, I. Molecular Structures and Dynamics of the Stepwise Activation Mechanism of a Matrix Metalloproteinase Zymogen: Challenging the Cysteine Switch Dogma. United States: N. p., 2007. Web. doi:10.1021/ja073941l.
Rosenblum,G., Meroueh, S., Toth, M., Fisher, J., Fridman, R., Mobashery, S., & Sagi, I. Molecular Structures and Dynamics of the Stepwise Activation Mechanism of a Matrix Metalloproteinase Zymogen: Challenging the Cysteine Switch Dogma. United States. doi:10.1021/ja073941l.
Rosenblum,G., Meroueh, S., Toth, M., Fisher, J., Fridman, R., Mobashery, S., and Sagi, I. Mon . "Molecular Structures and Dynamics of the Stepwise Activation Mechanism of a Matrix Metalloproteinase Zymogen: Challenging the Cysteine Switch Dogma". United States. doi:10.1021/ja073941l.
@article{osti_959763,
title = {Molecular Structures and Dynamics of the Stepwise Activation Mechanism of a Matrix Metalloproteinase Zymogen: Challenging the Cysteine Switch Dogma},
author = {Rosenblum,G. and Meroueh, S. and Toth, M. and Fisher, J. and Fridman, R. and Mobashery, S. and Sagi, I.},
abstractNote = {Activation of matrix metalloproteinase zymogen (pro-MMP) is a vital homeostatic process, yet its molecular basis remains unresolved. Using stopped-flow X-ray spectroscopy of the active site zinc ion, we determined the temporal sequence of pro-MMP-9 activation catalyzed by tissue kallikrein protease in milliseconds to several minutes. The identity of three intermediates seen by X-ray spectroscopy was corroborated by molecular dynamics simulations and quantum mechanics/molecular mechanics calculations. The cysteine-zinc interaction that maintains enzyme latency is disrupted via active-site proton transfers that mediate transient metal-protein coordination events and eventual binding of water. Unexpectedly, these events ensue as a direct result of complexation of pro-MMP-9 and kallikrein and occur before proteolysis and eventual dissociation of the pro-peptide from the catalytic site. Here we demonstrate the synergism among long-range protein conformational transitions, local structural rearrangements, and fine atomic events in the process of zymogen activation.},
doi = {10.1021/ja073941l},
journal = {Journal of the American Chemical Society},
number = ,
volume = 129,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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