Some phytotoxic glycopeptides from Ceratocystis ulmi, the Dutch Elm Disease pathogen.
Ceratocystis ulmi, the causal agent of Dutch Elm Disease, produces phytotoxic glycopeptides in culture. A mixture of phytotoxic glycopeptides has been prepared by affinity chromatography on a concanavalin A-Sepharose column and collectively they have been termed the toxin. The polydisperse component that makes up the majority of toxin (80%) by weight has a molecular weight of about 2.7.10(5). The large molecular weight component (less than 5%) elutes at the void volume of a Bio-Gel A 50 m column. The other component (15%) appears as a trailing peak on the edge of the major component and has an approximate molecular weight of 7.10(4). The toxin is composed of 83% sugar residues, primarily rhamnose and mannose, and 7% amino acid residues. Methylation analysis coupled with mild acid hydrolysis indicates that the backbone of the polysaccharide portion of the toxin is composed of alpha -1,6-linked mannosyl residues with a 3-linked terminal rhamnosyl residue linked to C-3 of almost every mannosyl residue. The carbohydrate portion of the molecule is linked to the peptide via O-glycosidic linkages to both threonyl and seryl residues. All three components of the toxin are capable of causing wilt in stem cuttings of American elm.
D000596:Amino Acids / Q000032:analysis; D001203:Ascomycota / Q000378:metabolism*; D006020:Glycopeptides / Q000032:analysis / Q000378:metabolism*; D006027:Glycosides / Q000032:analysis; D006601:Hexoses / Q000032:analysis; D008970:Molecular Weight; D010935:Plant Diseases; D010944:Plants / Q000382:microbiology*; D014118:Toxins, Biological / Q000378:metabolism*
D000596:Amino Acids; D006020:Glycopeptides; D006027:Glycosides; D006601:Hexoses; D014118:Toxins, Biological