Please use this identifier to cite or link to this item: http://ktisis.cut.ac.cy/handle/10488/6620
Title: Two ligand-binding sites in the O2-sensing signal transducer HemAT: implications for ligand recognition/discrimination and signaling
Authors: Pinakoulaki, Eftychia 
Yoshimura, Hideaki 
Yoshioka, Shiro 
Aono, Shigetoshi 
Varotsis, Constantinos 
Daskalakis, Evangelos 
Pinakoulaki, Eftychia 
Keywords: Fourier transform infrared spectroscopy
Heme
Oxygen
Binding sites (Biochemistry)
Electric fields
Photochemistry
Gas
Issue Date: 2006
Publisher: National academy of sciences
Source: Proceedings of the national academy of sciences of the United States of America, 2006, Volume 103, Issue 40, Pages 14796-14801
Abstract: We have identified a ligand (CO) accommodation cavity in the signal transducer sensor protein HemAT (heme-based aerotactic transducer) that allows us to gain single-molecule insights into the mechanism of gas sensor proteins. Specific mutations that are distal and proximal to the heme were designed to perturb the electrostatic field near the ligand that is bound to the heme and near the accommodated ligand in the cavity. We report the detection of a second site in heme proteins in which the exogenous ligand is accommodated in an internal cavity. The conformational gate that directs the ligand-migration pathway from the distal to the proximal site of the heme, where the ligand is trapped, has been identified. The data provide evidence that the heme pocket is the specific ligand trap and suggest that the regulatory mechanism may be tackled starting from more than one position in the protein. Based on the results, we propose a dynamic coupling between the two distinct binding sites as the underlying allosteric mechanism for gas recognition/discrimination that triggers a conformational switch for signaling by the oxygen sensor protein HemAT
URI: http://ktisis.cut.ac.cy/handle/10488/6620
ISSN: 00278424
DOI: 10.1073/pnas.0604248103
Rights: © 2006 by The National Academy of Sciences of the USA
Appears in Collections:Άρθρα/Articles

Show full item record

SCOPUSTM   
Citations 10

24
checked on May 25, 2017

WEB OF SCIENCETM
Citations 10

24
checked on May 26, 2017

Page view(s)

10
Last Week
1
Last month
checked on May 25, 2017

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.