Reference Report for IND20360804
Title: | Purification and partial characterization of a host-specific pathotoxin from culture filtrates of Septoria glycines. |
Authors: | Song, H.S., Lim, S.M., Clark, J.M. Jr. |
Source: | Phytopath.1993, 83(6):659-661 |
Abstract: | A host-specific pathotoxin isolated from culture filtrate of Septoria glycines caused typical symptoms of brown spot disease on cotyledons and leaves of soybean. This toxin was stable until autoclaving, but drying the toxin under flash-evaporation at 46 C in vacuo destroyed over 99% of the toxin activity. The toxin was purified approximately 16,000-fold by sequential carboxymethyl (CM)-cellulose treatment, diethylaminoethyl (DEAE)-cellulose chromatography, dialysis, gel filtration, and 5% charcoal treatment. The purified toxin appeared to be a polysaccharide because it was resistant to proteinase K, but oxidation with 35 mM IO4- and incubation with alpha-mannosidase, beta-galactosidase, or beta-glucosidase markedly reduced toxin activity. The partial characterization of the purified toxin as a polysaccharide was supported by positive results with phenol-H2SO4 and carbazole tests and increased generation of reducing center analysis (detected by reduction with NaB3H4) after acid hydrolysis. The combined results indicated that the toxin is an approximately 20,000-Da polysaccharide with a high content of uronic acids and perhaps low levels of mannose, galactose, and glucose. |