A ZnS4Structural Zinc Site in theHelicobacter pyloriFerric Uptake Regulator

Biochemistry ◽  
2009 ◽  
Vol 48 (24) ◽  
pp. 5582-5591 ◽  
Author(s):  
Sylvia Vitale ◽  
Caroline Fauquant ◽  
David Lascoux ◽  
Kristine Schauer ◽  
Christine Saint-Pierre ◽  
...  
Keyword(s):  
2009 ◽  
Vol 1201 ◽  
Author(s):  
Pekka Tapio Neuvonen ◽  
Lasse Vines ◽  
Klaus Magnus Johansen ◽  
Anders Hallén ◽  
Bengt Gunnar Svensson ◽  
...  

AbstractSecondary ion mass spectrometry has been applied to study the transportation of Na and Li in hydrothermally grown ZnO. A dose of 1015 cm-2 of Na+ was implanted into ZnO to act as a diffusion source. A clear trap limited diffusion is observed at temperatures above 550 °C. From these profiles, an activation energy for the transport of Na of ∼1.7 eV has been extracted. The prefactor for the diffusion constant and the solid solubility of Na cannot be deduced independently from the present data but their product estimated to be ∼3 × 1016 cm-1s-1. A dissociation energy of ∼2.4 eV is extracted for the trapped Na. The measured Na and Li profiles show that Li and Na compete for the same traps and interact in a way that Li is depleted from Na-rich regions. This is attributed to a lower formation energy of Na-on-zinc-site than that for Li-on-zinc-site defects and the zinc vacancy is considered as a major trap for migrating Na and Li atoms. Consequently, the diffusivity of Li is difficult to extract accurately from the present data, but in its interstitial configuration Li is indeed highly mobile having a diffusivity in excess of 10-11 cm2s-1 at 500 °C.


1998 ◽  
Vol 275-276 ◽  
pp. 215-221 ◽  
Author(s):  
Kimber Clark-Baldwin ◽  
Adam R. Johnson ◽  
Yen-Wen Chen ◽  
Eugene E. Dekker ◽  
James E. Penner-Hahn

2007 ◽  
Vol 1774 (2) ◽  
pp. 312-322 ◽  
Author(s):  
Stefano Mangani ◽  
Manuela Benvenuti ◽  
Arthur J.G. Moir ◽  
Maria Ranieri-Raggi ◽  
Daniela Martini ◽  
...  

2003 ◽  
Vol 125 (33) ◽  
pp. 9962-9969 ◽  
Author(s):  
Daniel A. Tobin ◽  
Jennifer S. Pickett ◽  
Heather L. Hartman ◽  
Carol A. Fierke ◽  
James E. Penner-Hahn

2009 ◽  
Vol 11 (6) ◽  
pp. 975-983 ◽  
Author(s):  
Erik G. Brandt ◽  
Mikko Hellgren ◽  
Tore Brinck ◽  
Tomas Bergman ◽  
Olle Edholm

2018 ◽  
Vol 36 (2) ◽  
pp. 021503
Author(s):  
Zhonghua Xu ◽  
Kun Tang ◽  
Shunming Zhu ◽  
Jingrui Ma ◽  
Jiandong Ye ◽  
...  
Keyword(s):  

2017 ◽  
Vol 114 (52) ◽  
pp. 13661-13666 ◽  
Author(s):  
Rongfeng Zhu ◽  
Yanqun Song ◽  
Haiping Liu ◽  
Yufei Yang ◽  
Shenlin Wang ◽  
...  

Metalloregulators allosterically control transcriptional activity through metal binding-induced reorganization of ligand residues and/or hydrogen bonding networks, while the coordination atoms on the same ligand residues remain seldom changed. Here we show that the MarR-type zinc transcriptional regulator ZitR switches one of its histidine nitrogen atoms for zinc coordination during the allosteric control of DNA binding. The Zn(II)-coordination nitrogen on histidine 42 within ZitR’s high-affinity zinc site (site 1) switches from Nε2 to Nδ1 upon Zn(II) binding to its low-affinity zinc site (site 2), which facilitates ZitR’s conversion from the nonoptimal to the optimal DNA-binding conformation. This histidine switch-mediated cooperation between site 1 and site 2 enables ZitR to adjust its DNA-binding affinity in response to a broad range of zinc fluctuation, which may allow the fine tuning of transcriptional regulation.


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