<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Shinde, Sandip S.</style></author><author><style face="normal" font="default" size="100%">Minami, Atsushi</style></author><author><style face="normal" font="default" size="100%">Chen, Zhi</style></author><author><style face="normal" font="default" size="100%">Tokiwano, Tetsuo</style></author><author><style face="normal" font="default" size="100%">Toyomasu, Tomonobu</style></author><author><style face="normal" font="default" size="100%">Kato, Nobuo</style></author><author><style face="normal" font="default" size="100%">Sassa, Takeshi</style></author><author><style face="normal" font="default" size="100%">Oikawa, Hideaki</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cyclization mechanism of phomopsene synthase: mass spectrometry based analysis of various site-specifically labeled terpenes</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Antibiotics</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2017</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAY</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">632-638</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Elucidation of the cyclization mechanism catalyzed by terpene synthases is important for the rational engineering of terpene cyclases. We developed a chemoenzymatic method for the synthesis of systematically deuterium-labeled geranylgeranyl diphosphate ( GGPP), starting from site-specifically deuterium-labeled isopentenyl diphosphates (IPPs) using IPP isomerase and three prenyltransferases. We examined the cyclization mechanism of tetracyclic diterpene phomopsene with phomopsene synthase. A detailed EI-MS analysis of phomopsene labeled at various positions allowed us to propose the structures corresponding to the most intense peaks, and thus elucidate a cyclization mechanism involving double 1,2-alkyl shifts and a 1,2-hydride shift via a dolabelladien-15-yl cation. Our study demonstrated that this newly developed method is highly sensitive and provides sufficient information for a reliable assignment of the structures of fragmented ions.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">1.730</style></custom4></record></records></xml>