Proteins and carbohydrates 6

Question 1

Why do bacteria use catch bonds to adhere to surfaces?

Answer 1

It prevents them from dislodging at high shear forces yet enables movement (e.g. to search for nutrients) at low shear forces

Question 2

How long is the backbone of a single amino acid?

Answer 2

0.4 nm

Question 3

What happens to pyranoses at high forces?

Answer 3

At high forces, conformational transitions of the pyranose ring add enthalpic elasticity. If you stretch a monosaccharide enough, its preffered conformation will change. The preffered conformation will revert to the original one once the applied stretching force is removed.

Question 4

How does the stiffness of polysaccharides compare to protein chains and why?

Answer 4

Polysaccharides are stiffer than protein chains due to bending rigidity arising from the pyranose ring and glycosidic linkage.