<?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%">Andrade, S. L.</style></author><author><style face="normal" font="default" size="100%">Brondino, C. D.</style></author><author><style face="normal" font="default" size="100%">Kamenskaya, E. O.</style></author><author><style face="normal" font="default" size="100%">Levashov, A. V.</style></author><author><style face="normal" font="default" size="100%">Moura, J. J.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Kinetic behavior of Desulfovibrio gigas aldehyde oxidoreductase encapsulated in reverse micelles</style></title><secondary-title><style face="normal" font="default" size="100%">Biochem Biophys Res Commun</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">*Micelles</style></keyword><keyword><style  face="normal" font="default" size="100%">Aldehyde Reductase/*metabolism</style></keyword><keyword><style  face="normal" font="default" size="100%">Aldehydes/metabolism</style></keyword><keyword><style  face="normal" font="default" size="100%">Desulfovibrio/*enzymology</style></keyword><keyword><style  face="normal" font="default" size="100%">Kinetics</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year><pub-dates><date><style  face="normal" font="default" size="100%">Aug 15</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=12890482 </style></url></web-urls></urls><number><style face="normal" font="default" size="100%">1</style></number><volume><style face="normal" font="default" size="100%">308</style></volume><pages><style face="normal" font="default" size="100%">73-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;We report the kinetic behavior of the enzyme aldehyde oxidoreductase (AOR) from the sulfate reducing bacterium Desulfovibrio gigas (Dg) encapsulated in reverse micelles of sodium bis-(2-ethylhexyl) sulfosuccinate in isooctane using benzaldehyde, octaldehyde, and decylaldehyde as substrates. Dg AOR is a 200-kDa homodimeric protein that catalyzes the conversion of aldehydes to carboxylic acids. Ultrasedimentation analysis of Dg AOR-containing micelles showed the presence of 100-kDa molecular weight species, confirming that the Dg AOR subunits can be dissociated. UV-visible spectra of encapsulated Dg AOR are indistinguishable from the enzyme spectrum in solution, suggesting that both protein fold and metal cofactor are kept intact upon encapsulation. The catalytic constant (k(cat)) profile as a function of the micelle size W(0) (W(0)=[H(2)O]/[AOT]) using benzaldehyde as substrate showed two bell-shaped activity peaks at W(0)=20 and 26. Furthermore, enzymatic activity for octaldehyde and decylaldehyde was detected only in reverse micelles. Like for the benzaldehyde kinetics, two peaks with both similar k(cat) values and W(0) positions were obtained. EPR studies using spin-labeled reverse micelles indicated that octaldehyde and benzaldehyde are intercalated in the micelle membrane. This suggests that, though Dg AOR is found in the cytoplasm of bacterial cells, the enzyme may catalyze the reaction of substrates incorporated into a cell membrane.&lt;/p&gt;
</style></abstract><accession-num><style face="normal" font="default" size="100%">12890482</style></accession-num><notes><style face="normal" font="default" size="100%">&lt;p&gt;0006-291X (Print)0006-291X (Linking)Journal ArticleResearch Support, Non-U.S. Gov't&lt;/p&gt;
</style></notes><auth-address><style face="normal" font="default" size="100%">REQUIMTE/CQFB, Departamento de Qui;mica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica 2829-516, Portugal.</style></auth-address></record></records></xml>