Why is trehalose a non-reducing sugar?

Because cellobiose, maltose and gentiobiose are hemiacetals they are all reducing sugars (oxidized by Tollen’s reagent). Trehalose, a disaccharide found in certain mushrooms, is a bis-acetal, and is therefore a non-reducing sugar.

Is trehalose a reducing sugar?

Trehalose (α-d-glucopyranosyl α-d-glucopyranoside) is a non-reducing disaccharide in which the two d-glucose residues are linked through the anomeric positions to one another. Trehalose is widespread in bacteria, fungi, yeast, insects and plants, but is absent from vertebrates.

How does trehalose stabilize cellular molecules?

It is hypothesized that trehalose prevents the inactivation and aggregation of proteins at lower temperature and stabilizes the cell membrane by delaying the onset of phase shift from liquid crystal to gel state.

How does trehalose stabilize proteins?

In solution, trehalose has been ob- served to stabilize RNase A by increasing the surface tension of the medium, which leads to the preferential hydration of the protein (8, 9). These studies have been carried out using a representative protein at a few selected conditions only.

Why is cellobiose a reducing sugar?

Similar to maltose, cellobiose is a reducing sugar since it can turn into an open-chain form with its functional group acting as a reducing agent. This means that it can be hydrolyzed not just enzymatically but also via acid hydrolysis. Cellobiose is similar to cellulose in having glucose constituents.

Why is trehalose resistant to acid hydrolysis?

Unlike maltose, trehalose is a nonreducing sugar. The glycosidic bond that joins the two glucose units keeps trehalose in a closed-ring form. Consequently, the aldehyde or the ketone ends cannot bind with lysine or arginine of proteins. Thus, trehalose is resistant to acid hydrolysis.

How does trehalose prevent aggregation?

Interesting bioprotective actions offered by trehalose include its ability to stabilize proteins, cell membranes and liposomes, to decrease intracellular ice formation during freezing, and to prevent protein aggregation (reviewed in ref. 11).

Why is trehalose an exceptional protein stabilizer?

Trehalose, a naturally occurring osmolyte, is known to be an exceptional stabilizer of proteins and helps retain the activity of enzymes in solution as well as in the freeze-dried state. There is a decrease in the heat capacity of protein denaturation (DeltaCp) in trehalose solutions for all the studied proteins.

What is the difference between maltose and trehalose?

Both trehalose and maltose are disaccharides containing two alpha glucose units. The key difference between trehalose and maltose is that trehalose contains a 1,1-glycosidic linkage, whereas maltose contains a 1,4-glycosidic linkage. Moreover, trehalose is a non-reducing sugar, while maltose is a reducing sugar.

What happens when cellobiose is hydrolysed?

Cellobiose is hydrolyzed into glucose by intracellular β-glucosidase or into glucose and glucose-1-P by CBP in the cytosol (Fig. 9.1(c)).

Is trehalose more or less susceptible to acid hydrolysis?

Trehalose is non-reducing because it is formed by the coupling of two reducing groups. This bond also ensures that trehalose is not affected by acid hydrolysis. Therefore, it can maintain its stability even in acidic environments and high temperatures.

What is disaccharide trehalose?

Trehalose is a naturally occurring disaccharide comprised of two molecules of glucose. The sugar is widespread in many species of plants and animals, where its function appears to be to protect cells against desiccation, but is not found in mammals.

What is the stabilizing effect of trehalose?

This stabilizing effect of trehalose is a property of its structure and its stereochemistry. X-ray diffraction studies show that trehalose fits well between the polar head groups of the lipids with multiple sites of interaction.

What is intestinal trehalase?

Like other intestinal hydrolases, trehalase is a glycosylphosphatidylinositol-anchored protein. 72 Individuals with a defect in intestinal trehalase suffer diarrhoea when foods with high trehalose content are ingested. While trehalose is a significant sugar in its own right, it is also found at the core of a range of oligosaccharides.

What is tretrehalose and why is it important?

Trehalose is the major sugar in the hemolymph and thorax muscle of insects, and it is converted to glucose and consumed during flight. It is also an important source of energy and carbon in fungal spores and is utilized during the germination process.

Is trehalose safe to eat?

A January article in Food Chemistry showed that in mice, doses of 1.25gms/kg, 2.5gms/kg, and 5gms/kg were safe Multiple toxicity studies of trehalose in mice by intragastric administration : “The results obtained in the present study could support the conclusion that consumption of trehalose has no adverse effects for humans.”