Glycosylphosphatidylinositol-anchored glucanosyltransferases play an active role in the biosynthesis of the fungal cell wall.

A novel 1,3-beta-glucanosyltransferase isolated from the cell wall of Aspergillus fumigatus was recently characterized. This enzyme splits internally a 1,3-beta-glucan molecule and transfers the newly generated reducing end to the non-reducing end of another 1, 3-beta-glucan molecule forming a 1,3-beta linkage, resulting in the elongation of 1,3-beta-glucan chains. The GEL1 gene encoding this enzyme was cloned and sequenced.

Tea tree oil causes K+ leakage and inhibits respiration in Escherichia coli.

Concentrations of tea tree oil (TTO) which inhibit or decrease growth of Escherichia coli also inhibit glucose-dependent respiration and stimulate the leakage of intracellular K+. Stationary phase cells are more tolerant to these TTO effects than exponential phase cells.

Differential patterns of activity displayed by two exo-beta-1,3-glucanases associated with the Aspergillus fumigatus cell wall.

Two exo-beta-1,3-glucanases (herein designated exoG-I and exoG-II) were isolated from the cell wall autolysate of the filamentous fungus Aspergillus fumigatus and purified by ion-exchange, hydrophobic-interaction, and gel filtration chromatographies. Molecular masses estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography were 82 kDa for the monomeric exoG-I and 230 kDa for the dimeric exoG-II. exoG-I and exoG-II were glycosylated, and N glycans accounted, respectively, for 2 and 44 kDa.

Purification and characterization of an endo-1,3-beta-glucanase from Aspergillus fumigatus.

An endo-1,3-beta-glucanase was purified from a cell wall autolysate of Aspergillus fumigatus. This beta-glucanase activity was associated with a glycosylated 74-kDa protein. Using a sensitive colorimetric assay and a high-performance anion-exchange chromatography with a pulsed electrochemical detector for product analysis, it was shown that the endoglucanase hydrolysed exclusively linear 1,3-beta-glucan chains, had an optimum pH of 7.