Open AccessA Transglucosylase from Sclerotinia libertiana
Author(s) -
Ryōichi Yamamoto,
Donald J. Nevins
Publication year - 1979
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.64.2.193
Subject(s) - sclerotinia , glucanase , cellobiose , chemistry , enzyme , biochemistry , stereochemistry , substrate (aquarium) , biology , botany , cellulase , ecology
A Sclerotinia enzyme preparation with predominant exo-beta-(1-->3)-glucanase activity has the capacity to mediate the formation of tetrasaccharide from 3-O-beta-cellobiosyl-d-glucose or cellotriose, and a pentasaccharide from 3-O-beta-cellotriosyl-d-glucose or cellotetraose. Transglucosylation is not observed when the enzyme is incubated in the presence of laminaritriose, laminaritetraose, or cellobiose. Substrate specificity of the reaction therefore resembles certain features of exo-beta-(1-->4)-glucanases. The optimum pH of the activity is 5.5 and the reaction is inhibited by nojirimycin but not by glucono-1,5-lactone. In contrast to the Sclerotinia glucanase, a Basidiomycete exo-beta-(1-->3)-glucanase has no apparent transglucosylase activity. The results indicate that a transglucosylase may have been an undetected constituent in exo-beta-(1-->3)-glucanase preparations used for promoting growth in auxin-depleted tissues.