Trehalose Metabolism: Enzymatic Pathways and Physiological Functions

Abstract

Trehalose is a disaccharide (α-D-glucopyranosyl α-D-glucopyranoside) commonly found in many fungi and present in particularly high concentrations in stationary-phase cells and survival forms. For a long time, trehalose was considered to be a storage carbohydrate, accumulated under conditions of imminent carbon shortage and mobilized under prolonged starvation conditions. However, several unusual features of trehalose metabolism have been discovered in recent years. Trehalose levels often correlate closely with stress resistance and in vitro experiments have shown a remarkable capacity of high trehalose concentrations in conferring protection to denaturation of proteins and membranes under stress conditions. The role of trehalose in stress protection is now well established.