Date of Award
2008
Degree Type
Thesis
Degree Name
Master of Science
Program
Biology
Supervisor
Dr. Mark A. Bernards
Second Advisor
Dr. Charlie Trick
Third Advisor
Dr. Mark Gijzen
Abstract
Three ginsenoside-deglycosylating enzymes have been purified 13- to 25-fold, from Pythium irregulare culture filtrates, by a four-step purification protocol. The three glycosidases are relatively high molecular weight (a homodimer of 78 kDa subunits and two monomeric enzymes of 57 and 61 kDa), acidic proteins, sharing these properties with a series of other saponin-glycosidases. They were induced in cultures grown in the presence of ginsenosides and they have apparently, different glycosidic activities (1→6 versus 1→2). Primary sequence analysis identified them as glycosidases, but did not relate them to other saponin-deglycosylating enzymes. While no definite conclusions can be drawn regarding the involvement of these glycosidases in pathogenicity, it is possible that these enzymes help the oomycete find its host or obtain nutrients and/or growth factors from its environment. These are the first glycosidases purified from a Pythium species and provide a starting point for future characterization studies.
Recommended Citation
Neculai, M. Andreea, "PURIFICATION AND CHARACTERIZATION OF EXTRACELLULAR GLYCOSIDASES FROM THE GINSENG ROOT PATHOGEN, PYTHIUM IRREGULARE" (2008). Digitized Theses. 4793.
https://ir.lib.uwo.ca/digitizedtheses/4793