Trehalose accumulation in Baudoinia compniacensis following abiotic stress

Baudoinia compniacensis is a microfungus recently described as the principal agent of fouling known as ‘‘warehouse staining’’, affecting building exteriors, fixtures and vegetation surfaces in areas proximate to distillery aging warehouses, commercial bakeries and other areas subject to low-level ethanol vapour exposure. The surfaces most affected tend to be highly exposed and undergo extreme diurnal temperature fluctuations. In previous work, we have demonstrated the existence of heat-inducible putative chaperone proteins that may also be induced by low-level exposures to ethanol vapour (e.g., <10 ppm). The present study investigated the cellular accumulation of trehalose, a disaccharide identified in some microorganisms to be important in the protection of cell components during adverse stress conditions, such as thermal stress. Following heat shock at 45 C, we observed a 2.5-fold accumulation of trehalose relative to unheated controls maintained at 26 C. Peak trehalose concentrations of 10 mg g 1 dry wt were seen at 90 min after heat treatment, followed by a gradual return to post-treatment by 150 min. Exposure of B. compniacensis cells to ethanol resulted in a similar increased accumulation of trehalose compared to unexposed controls. These findings imply that trehalose may be important in the tolerance of this fungus to abiotic stresses, such as heat and solvent exposure, and suggest future research directions for the control and prevention of warehouse staining. 2009 Elsevier Ltd. All rights reserved.