Toward Intelligent Materials - Molecular Self-Assembly: Advances and Applications - page 11

Figure 1.5 Potential registries of A (16-23), KLVFFAED. Favorable

cross-strand pairings for each registry are highlighted in
color where the negatively charged residues E and D side
chains associate with the positively charged K side chain.
This peptide was backbone capped, as was A

β

β

(16-22), with

N-terminal acetyl and C-terminal -NH .

2

A B

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0.0

0 5 10 15 20 25 30 35 40 45 50

Time [ms]

C D

5.8Å

4.2Å

Figure 1.6 ( ) Electron micrograph of KLVFFAED peptide assembled

under neutral conditions (identical to A

A

β

(16-22) [23]) for

a week into 15-50 nm bundled sheets. ( ) 13 C{ 15 N} REDOR

of KL[1- 13 C]VFF[ 15 N]AED. Solid black line is the calculated
13

B

C{ 15 N} REDOR curve for 13 C- 15 N distances shown in (

)
with an N-C-N angle of 156°, consistent with in-register
anti-parallel

C

β

13

C{ 15 N}REDOR curve for out-of-

-sheets.

register

β

-sheets (red) and parallel

β

-sheets (dashed line).

( D ) Model for in-register anti-parallel A

β

(16-23)

β

-sheet

consistent with the NMR distance constraints.

In longer peptide sequences, the sheer number of interactions
could well attenuate the global morphological attenuation of single