BioNMR
NMR aggregator & online community since 2003
BioNMR    
Learn or help to learn NMR - get free NMR books!
 

Go Back   BioNMR > Educational resources > Journal club
Advanced Search
Home Forums Wiki NMR feeds Downloads Register Today's Posts



Jobs Groups Conferences Literature Pulse sequences Software forums Programs Sample preps Web resources BioNMR issues


Webservers
NMR processing:
MDD
NMR assignment:
Backbone:
Autoassign
MARS
UNIO Match
PINE
Side-chains:
UNIO ATNOS-Ascan
NOEs:
UNIO ATNOS-Candid
UNIO Candid
ASDP
Structure from NMR restraints:
Ab initio:
GeNMR
Cyana
XPLOR-NIH
ASDP
UNIO ATNOS-Candid
UNIO Candid
Fragment-based:
BMRB CS-Rosetta
Rosetta-NMR (Robetta)
Template-based:
GeNMR
I-TASSER
Refinement:
Amber
Structure from chemical shifts:
Fragment-based:
WeNMR CS-Rosetta
BMRB CS-Rosetta
Homology-based:
CS23D
Simshift
Torsion angles from chemical shifts:
Preditor
TALOS
Promega- Proline
Secondary structure from chemical shifts:
CSI (via RCI server)
TALOS
MICS caps, β-turns
d2D
PECAN
Flexibility from chemical shifts:
RCI
Interactions from chemical shifts:
HADDOCK
Chemical shifts re-referencing:
Shiftcor
UNIO Shiftinspector
LACS
CheckShift
RefDB
NMR model quality:
NOEs, other restraints:
PROSESS
PSVS
RPF scores
iCing
Chemical shifts:
PROSESS
CheShift2
Vasco
iCing
RDCs:
DC
Anisofit
Pseudocontact shifts:
Anisofit
Protein geomtery:
Resolution-by-Proxy
PROSESS
What-If
iCing
PSVS
MolProbity
SAVES2 or SAVES4
Vadar
Prosa
ProQ
MetaMQAPII
PSQS
Eval123D
STAN
Ramachandran Plot
Rampage
ERRAT
Verify_3D
Harmony
Quality Control Check
NMR spectrum prediction:
FANDAS
MestReS
V-NMR
Flexibility from structure:
Backbone S2
Methyl S2
B-factor
Molecular dynamics:
Gromacs
Amber
Antechamber
Chemical shifts prediction:
From structure:
Shiftx2
Sparta+
Camshift
CH3shift- Methyl
ArShift- Aromatic
ShiftS
Proshift
PPM
CheShift-2- Cα
From sequence:
Shifty
Camcoil
Poulsen_rc_CS
Disordered proteins:
MAXOCC
Format conversion & validation:
CCPN
From NMR-STAR 3.1
Validate NMR-STAR 3.1
NMR sample preparation:
Protein disorder:
DisMeta
Protein solubility:
camLILA
ccSOL
Camfold
camGroEL
Zyggregator
Isotope labeling:
UPLABEL
Solid-state NMR:
sedNMR


Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
  #1  
Old 12-04-2013, 03:12 PM
nmrlearner's Avatar
Senior Member
 
Join Date: Jan 2005
Posts: 23,777
Points: 193,617, Level: 100
Points: 193,617, Level: 100 Points: 193,617, Level: 100 Points: 193,617, Level: 100
Level up: 0%, 0 Points needed
Level up: 0% Level up: 0% Level up: 0%
Activity: 50.7%
Activity: 50.7% Activity: 50.7% Activity: 50.7%
Last Achievements
Award-Showcase
NMR Credits: 0
NMR Points: 193,617
Downloads: 0
Uploads: 0
Default NMR-monitored titration of acid-stress bacterial chaperone HdeA reveals that Asp and Glu charge neutralization produces a loosened dimer structure in preparation for protein unfolding and chaperone activation

NMR-monitored titration of acid-stress bacterial chaperone HdeA reveals that Asp and Glu charge neutralization produces a loosened dimer structure in preparation for protein unfolding and chaperone activation

Abstract

HdeA is a periplasmic chaperone found in several gram-negative pathogenic bacteria that are linked to millions of cases of dysentery per year worldwide. After the protein becomes activated at low pH, it can bind to other periplasmic proteins, protecting them from aggregation when the bacteria travel through the stomach on their way to colonize the intestines. It has been argued that one of the major driving forces for HdeA activation is the protonation of aspartate and glutamate side chains. The goal for this study, therefore, was to investigate, at the atomic level, the structural impact of this charge neutralization on HdeA during the transition from near-neutral conditions to pH 3.0, in preparation for unfolding and activation of its chaperone capabilities. NMR spectroscopy was used to measure pKa values of Asp and Glu residues and monitor chemical shift changes. Measurements of R2/R1 ratios from relaxation experiments confirm that the protein maintains its dimer structure between pH 6.0 and 3.0. However, calculated correlation times and changes in amide protection from hydrogen/deuterium exchange experiments provide evidence for a loosening of the tertiary and quaternary structures of HdeA; in particular, the data indicate that the dimer structure becomes progressively weakened as the pH decreases. Taken together, these results provide insight into the process by which HdeA is primed to unfold and carry out its chaperone duties below pH 3.0, and it also demonstrates that neutralization of aspartate and glutamate residues is not likely to be the sole trigger for HdeA dissociation and unfolding.




More...
Reply With Quote


Did you find this post helpful? Yes | No

Reply
Similar Threads
Thread Thread Starter Forum Replies Last Post
Biochemists reveal interaction between tumor suppressor protein and chaperone - News-Medical.net
Biochemists reveal interaction between tumor suppressor protein and chaperone - News-Medical.net <img alt="" height="1" width="1" /> Biochemists reveal interaction between tumor suppressor protein and chaperone News-Medical.net Using nuclear magnetic resonance (NMR) spectroscopy, the scientists at the Bavarian NMR Center in Garching were able for the first time to characterize the interaction surfaces between Hsp90 and p53 and show that p53 binds to Hsp90 in an already ... Read here
nmrlearner Online News 0 09-08-2011 08:24 AM
NMR spectroscopy of 14-3-3? reveals a flexible C-terminal extension. Differentiation of the chaperone and phosphoserine binding activities of 14-3-3?
NMR spectroscopy of 14-3-3? reveals a flexible C-terminal extension. Differentiation of the chaperone and phosphoserine binding activities of 14-3-3? NMR spectroscopy of 14-3-3? reveals a flexible C-terminal extension. Differentiation of the chaperone and phosphoserine binding activities of 14-3-3? Biochem J. 2011 May 10; Authors: Williams DM, Ecroyd H, Goodwin KL, Dai H, Fu H, Woodcock JM, Zhang L, Carver JA Intracellular 14-3-3 proteins bind to many proteins, via a specific phosphoserine motif, regulating diverse cellular tasks including cell...
nmrlearner Journal club 0 05-12-2011 03:40 PM
Common 'chaperone' protein found to work in surprising way, say Scripps ... - EurekAlert (press release)
Common 'chaperone' protein found to work in surprising way, say Scripps ... - EurekAlert (press release) <img alt="" height="1" width="1" /> Common 'chaperone' protein found to work in surprising way, say Scripps ... EurekAlert (press release) "None of these studies was able to pinpoint either what the client protein looked like in the complex or what part of Hsp90 was contacting the client." In the new study, the team used protein nuclear magnetic resonance (NMR) spectroscopy; ... and more &raquo; Read here
nmrlearner Online News 0 04-03-2011 10:00 PM
[NMR paper] Real time NMR monitoring of local unfolding of HIV-1 protease tethered dimer driven b
Real time NMR monitoring of local unfolding of HIV-1 protease tethered dimer driven by autolysis. Related Articles Real time NMR monitoring of local unfolding of HIV-1 protease tethered dimer driven by autolysis. FEBS Lett. 2001 May 18;497(1):59-64 Authors: Panchal SC, Bhavesh NS, Hosur RV Structural studies in proteases have been hampered because of their inherent autolytic function. However, since autolysis is known to be mediated via protein unfolding, careful monitoring of the autolytic reaction has the potential to throw light on the...
nmrlearner Journal club 0 11-19-2010 08:32 PM
[NMR paper] NMR structure and metal interactions of the CopZ copper chaperone.
NMR structure and metal interactions of the CopZ copper chaperone. Related Articles NMR structure and metal interactions of the CopZ copper chaperone. J Biol Chem. 1999 Aug 6;274(32):22597-603 Authors: Wimmer R, Herrmann T, Solioz M, Wüthrich K A recently discovered family of proteins that function as copper chaperones route copper to proteins that either require it for their function or are involved in its transport. In Enterococcus hirae the copper chaperone function is performed by the 8-kDa protein CopZ. This paper describes the NMR...
nmrlearner Journal club 0 11-18-2010 08:31 PM
[NMR paper] NMR solution structure of the periplasmic chaperone FimC.
NMR solution structure of the periplasmic chaperone FimC. Related Articles NMR solution structure of the periplasmic chaperone FimC. Nat Struct Biol. 1998 Oct;5(10):885-90 Authors: Pellecchia M, Güntert P, Glockshuber R, Wüthrich K The NMR structure of the 205-residue periplasmic chaperone FimC is presented. This protein consists of two globular domains with immunoglobulin-like folds connected by a 15-residue linker peptide. The relative orientation of the two domains is defined by hydrophobic contacts and an interdomain salt bridge. FimC...
nmrlearner Journal club 0 11-17-2010 11:15 PM
[NMR paper] NMR solution structure of the 21 kDa chaperone protein DnaK substrate binding domain:
NMR solution structure of the 21 kDa chaperone protein DnaK substrate binding domain: a preview of chaperone-protein interaction. Related Articles NMR solution structure of the 21 kDa chaperone protein DnaK substrate binding domain: a preview of chaperone-protein interaction. Biochemistry. 1998 Jun 2;37(22):7929-40 Authors: Wang H, Kurochkin AV, Pang Y, Hu W, Flynn GC, Zuiderweg ER The solution structure of the 21 kDa substrate-binding domain of the Escherichia coli Hsp70-chaperone protein DnaK (DnaK 386-561) has been determined to a precision...
nmrlearner Journal club 0 11-17-2010 11:06 PM
[NMR paper] NMR structure determination of the Escherichia coli DnaJ molecular chaperone: seconda
NMR structure determination of the Escherichia coli DnaJ molecular chaperone: secondary structure and backbone fold of the N-terminal region (residues 2-108) containing the highly conserved J domain. http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles NMR structure determination of the Escherichia coli DnaJ molecular chaperone: secondary structure and backbone fold of the N-terminal region (residues 2-108) containing the highly conserved J domain. Proc Natl Acad Sci U S A. 1994 Nov...
nmrlearner Journal club 0 08-22-2010 03:29 AM



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



BioNMR advertisements to pay for website hosting and domain registration. Nobody does it for us.



Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright, BioNMR.com, 2003-2013
Search Engine Friendly URLs by vBSEO 3.6.0

All times are GMT. The time now is 09:21 AM.


Map