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Encyclopedia of Physical Science and Technology EN002C-64 May 19, 2001 20:39
Biopolymers 209
FIGURE 1 (a) Formation of a linear polymer from monomer A with two functional groups and (b) formation of nonlinear
polymers from monomer B with three functional groups: (i) branched polymer, (ii) branch-on-branch polymer, and (iii)
network polymer.
A. Proteins increased, so also has our understanding of the relation-
ship between structure and function.
All proteins are polymers of α-amino acids, but they differ
in three-dimensional molecular structure and in the func-
1. Structure
tions they perform in living organisms. Protein molecules
can, for example, have structural, transporting, or regula- As mentioned earlier, the monomers of proteins are α-
tory roles; in addition, as antibodies they protect mammals amino acids. Such acids can exist in two configurations
from disease and as enzymes act as the most efficient cat- (see Fig. 2), but the strict stereochemical requirements
alysts known. As our knowledge of protein structure has of the processes involved in protein biosynthesis result
