Home Hydration Analogs Hydration Bridging Hydrophobic Surfaces Coil Formation
Beta-Sheet Formation Beta-Turn Formation Carboxypeptidase A Assembly References

SURFACE HYDRATION OF POLYPEPTIDES AND PROTEINS

1

2

3

4

5

6

7

8

9

10

VIII – Hydration-Directed Assembly

Just as the polypeptide chain has two prolines strategically-positioned to produce bends, the continuing chain has two glycines at positions 278 and 275 to initiate beta-turns and permit the hydrophobic surface of a leucine and two phenylalanines (as shown on the right below), to spontaneously move into position on the coil and release covalent linearly-ordered water from both surfaces.
































Glycine 278, by initiating the first beta-turn, permits the chain to move upward and bring the cationic side-chain of arginine 276 close enough to the anionic phenolic oxygen of tyrosine 277 to be bridged by a single water molecule as shown in B. Glycine 275, by initiating the second beta turn, then brings the chain back down to permit arginine 272 to couple directly with glutamate 292 above the coil and the two hydrophobic surfaces to produce a tight thermodynamically-stable union. As polypeptide folding and assembly continue, the same strategic placement of linear hydration disrupting peptides in the chain guide it into its final protein form and direct its enzymatic function. To view the role surface water may play in the continued assembly and function of this enzyme and three other proteins, check out www.linearwater.com.

Download PDF of this page   Download PDF Book  References Strategically-positioned glycines in the terminal segments of polypeptides provide for spontaneous and rapid assembly.