PMID- 20219471
OWN - NLM
STAT- MEDLINE
DCOM- 20100525
LR  - 20100329
IS  - 1089-8638 (Electronic)
IS  - 0022-2836 (Linking)
VI  - 397
IP  - 5
DP  - 2010 Apr 16
TI  - Intramolecular movements in EF-G, trapped at different stages in its GTP 
      hydrolytic cycle, probed by FRET.
PG  - 1245-60
LID - 10.1016/j.jmb.2010.02.039 [doi]
AB  - Elongation factor G (EF-G) is one of several GTP hydrolytic proteins (GTPases) 
      that cycles repeatedly on and off the ribosome during protein synthesis in 
      bacterial cells. In the functional cycle of EF-G, hydrolysis of guanosine 
      5'-triphosphate (GTP) is coupled to tRNA-mRNA translocation in ribosomes. GTP 
      hydrolysis induces conformational rearrangements in two switch elements in the G 
      domain of EF-G and other GTPases. These switch elements are thought to initiate 
      the cascade of events that lead to translocation and EF-G cycling between 
      ribosomes. To further define the coupling mechanism, we developed a new 
      fluorescent approach that can detect intramolecular movements in EF-G. We 
      attached a fluorescent probe to the switch I element (sw1) of Escherichia coli 
      EF-G. We monitored the position of the sw1 probe, relative to another fluorescent 
      probe anchored to the GTP substrate or product, by measuring the 
      distance-dependent, Forster resonance energy transfer between the two probes. By 
      analyzing EF-G trapped at five different functional states in its cycle, we could 
      infer the cyclical movements of sw1 within EF-G. Our results provide evidence for 
      conformational changes in sw1, which help to drive the unidirectional EF-G cycle 
      during protein synthesis. More generally, our approach might also serve to define 
      the conformational dynamics of other GTPases with their cellular receptors.
CI  - Copyright (c) 2010 Elsevier Ltd. All rights reserved.
FAU - Nguyen, Boray
AU  - Nguyen B
AD  - Department of Biochemistry, Faculty of Medicine & Dentistry, University of 
      Alberta, Edmonton, Alberta, Canada T6G 2H7.
FAU - Ticu, Cristina
AU  - Ticu C
FAU - Wilson, Kevin S
AU  - Wilson KS
LA  - eng
GR  - Canadian Institutes of Health Research/Canada
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20100226
PL  - Netherlands
TA  - J Mol Biol
JT  - Journal of molecular biology
JID - 2985088R
RN  - 0 (Escherichia coli Proteins)
RN  - 0 (Peptide Elongation Factor G)
RN  - 86-01-1 (Guanosine Triphosphate)
SB  - IM
MH  - Escherichia coli Proteins/chemistry/metabolism
MH  - *Fluorescence Resonance Energy Transfer
MH  - Guanosine Triphosphate/*metabolism
MH  - Hydrolysis
MH  - Molecular Dynamics Simulation
MH  - Movement
MH  - Peptide Elongation Factor G/*chemistry/metabolism
MH  - *Protein Biosynthesis
MH  - Protein Conformation
MH  - Ribosomes
EDAT- 2010/03/12 06:00
MHDA- 2010/05/26 06:00
CRDT- 2010/03/12 06:00
PHST- 2009/08/18 00:00 [received]
PHST- 2010/02/19 00:00 [revised]
PHST- 2010/02/22 00:00 [accepted]
PHST- 2010/03/12 06:00 [entrez]
PHST- 2010/03/12 06:00 [pubmed]
PHST- 2010/05/26 06:00 [medline]
AID - S0022-2836(10)00214-7 [pii]
AID - 10.1016/j.jmb.2010.02.039 [doi]
PST - ppublish
SO  - J Mol Biol. 2010 Apr 16;397(5):1245-60. doi: 10.1016/j.jmb.2010.02.039. Epub 2010 
      Feb 26.