(1-->6)-Beta-D-glucan as the cell wall binding site for Debaryomyces hansenii killer toxin.
OBJECTIVE
The aims of this study were to characterize the cell wall binding site of Debaryomyces hansenii killer toxin to provide a simple purification method and to determine some characteristics of this toxin.


RESULTS
Various linear (1-->6)-beta-D-glucans of different origins were effective competitive inhibitors of the toxin action. Periodate oxidation and 1H-NMR was used to determine the receptor nature. Affinity chromatography on pustulan-Sepharose column was used to purify D. hansenii killer toxin, probably a 23-kDa protein. The killer toxin character was cureless.


CONCLUSIONS
The investigation revealed that the killer toxin was mainly adsorbed by (1-->6)-beta-D-glucans. This is a low molecular weight protein, probably encoded by chromosomal genes.


CONCLUSIONS
The specificity of the killer toxin for its receptor provides an effective means to purify the killer toxin. This study is the first to identify the cell wall binding site of this killer toxin, a toxin with properties of industrial relevance.
Santos
A
A
Department of Microbiology, Biology Faculty, Complutense University of Madrid, 28040, Madrid, Spain.
Marquina
D
D
Barroso
J
J
Peinado
J M
JM
D001665:Binding Sites; D002473:Cell Wall / Q000737:chemistry* / Q000378:metabolism; D002846:Chromatography, Affinity; D005936:Glucans / Q000378:metabolism*; D055646:Killer Factors, Yeast; D011506:Proteins / Q000302:isolation & purification* / Q000378:metabolism*; D004718:Saccharomycetales / Q000378:metabolism*; D047071:beta-Glucans
D005936:Glucans; D055646:Killer Factors, Yeast; D011506:Proteins; D047071:beta-Glucans; C064197:beta-1,6-glucan