Biomedical Engineering Reference
In-Depth Information
Fig. 4.4
Model of hierarchical assembly of apatite nanocrystals mediated by glycine and glutamic
acid. Nanocrystals consisting of HAP core (purple) and ACP shell (light blue) aggregated
spontaneously and were dispersed in water. In the presence of indicated amino acids, nanocrystals
reassembled into different hierarchical structures. One-dimensional linear assemblies and two-
dimensional plate-like structures were formed in the presence of Gly and Glu, respectively.
Nanocrystals were connected by ACP surrounding HAP core. ACP transformed into thermody-
namically stable HAP, and, at the same time, HAP core rotated to the most stable orientation. As a
result, each HAP domain had the same crystallographic orientation and fused into single crystals.
Reprinted with permission from [
73
]. (Copyright 2007, American Chemical Society)
encapsulated within a membrane consisting of proteins. When a gene encoding
an artificial peptide is inserted into a gene encoding a membrane protein using
recombinant DNA technology, a chimeric protein consisting of the membrane
protein and the peptide is synthesized and displayed on the surface of the phage.
If the artificial peptide has the ability to bind to the target compound, the phage will
also be able to bind to that compound.
DNA sequences encoding 12-16 amino acids are usually inserted into a mem-
brane protein gene. In a typical experiment, up to 10
9
phages displaying 10
9
different peptide sequences can be used. First, 10
9
phages and the target compound
are mixed together. Phages that have affinity to the target compound are recovered
using an affinity chromatography-like technique. The recovered phages are infected
