<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gonzalez, P. J.</style></author><author><style face="normal" font="default" size="100%">Barrera, G. I.</style></author><author><style face="normal" font="default" size="100%">Rizzi, A. C.</style></author><author><style face="normal" font="default" size="100%">Moura, J. J.</style></author><author><style face="normal" font="default" size="100%">Passeggi, M. C.</style></author><author><style face="normal" font="default" size="100%">Brondino, C. D.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">EPR studies of the Mo-enzyme aldehyde oxidoreductase from Desulfovibrio gigas: an application of the Bloch-Wangsness-Redfield theory to a system containing weakly-coupled paramagnetic redox centers with different relaxation rates</style></title><secondary-title><style face="normal" font="default" size="100%">J Inorg Biochem</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Aldehyde Reductase/*chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Bacterial Proteins/*chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Desulfovibrio gigas/*enzymology</style></keyword><keyword><style  face="normal" font="default" size="100%">Electron Spin Resonance Spectroscopy</style></keyword><keyword><style  face="normal" font="default" size="100%">Molybdenum/*chemistry</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">Oct</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;dopt=Citation&amp;list_uids=19628281 </style></url></web-urls></urls><number><style face="normal" font="default" size="100%">10</style></number><volume><style face="normal" font="default" size="100%">103</style></volume><pages><style face="normal" font="default" size="100%">1342-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Electron transfer proteins and redox enzymes containing paramagnetic redox centers with different relaxation rates are widespread in nature. Despite both the long distances and chemical paths connecting these centers, they can present weak magnetic couplings produced by spin-spin interactions such as dipolar and isotropic exchange. We present here a theoretical model based on the Bloch-Wangsness-Redfield theory to analyze the dependence with temperature of EPR spectra of interacting pairs of spin 1/2 centers having different relaxation rates, as is the case of the molybdenum-containing enzyme aldehyde oxidoreductase from Desulfovibrio gigas. We analyze the changes of the EPR spectra of the slow relaxing center (Mo(V)) induced by the faster relaxing center (FeS center). At high temperatures, when the relaxation time T(1) of the fast relaxing center is very short, the magnetic coupling between centers is averaged to zero. Conversely, at low temperatures when T(1) is longer, no modulation of the coupling between metal centers can be detected.&lt;/p&gt;
</style></abstract><accession-num><style face="normal" font="default" size="100%">19628281</style></accession-num><notes><style face="normal" font="default" size="100%">&lt;p&gt;1873-3344 (Electronic)0162-0134 (Linking)Journal ArticleResearch Support, Non-U.S. Gov't&lt;/p&gt;
</style></notes><auth-address><style face="normal" font="default" size="100%">REQUIMTE, Departamento de Quimica, Centro de Quimica Fina e Biotecnologia, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.</style></auth-address></record></records></xml>