樓國隆Lou, Kuo-LongKuo-LongLou2006-07-262018-07-092006-07-262018-07-092001http://ntur.lib.ntu.edu.tw//handle/246246/22657Glucosyltransferases (GtfB/C/D) of Streptococcus mutans, a pathogen for human dental caries, synthesize water-insoluble glucan through the hydrolysis of sucrose. Genetic and biochemical approaches have identified several active sites of these enzymes, but no three-dimensional (3D) structural evidence is yet available to elucidate the subdomain arrangement and molecular mechanism of catalysis. Based on a combined sequence and secondary structure alignment against known crystal structures of segments from closely related proteins, we propose here the 3D model of an N-terminal domain essential for the sucrose binding and splitting in GtfB. A Tim-barrel of (K/L)8 structural characteristics is revealed and the structural correlation for two peptides is described.application/pdf615870 bytesapplication/pdfzh-TW國立臺灣大學醫學院口腔生物科學研究所GlucosyltransferaseStreptococcus mutansSucrase activityCatalytic domainThree-dimensional modelTim-barreljournal articlehttp://ntur.lib.ntu.edu.tw/bitstream/246246/22657/1/892314B002555.pdf