Datasheet

The early days of biochemistry were devoted to finding out a better way
to represent proteins — preferably in terms of a formula that would explain
their biological (or even nutritional) properties. Biochemists realized over
time that proteins were huge molecules (
macromolecules) made up of large
numbers of amino acids (typically from 100 to 500), picked out from a selec-
tion of 20 “flavors” with names such as alanine, glycine, tyrosine, glutamine,
and so on. Table 1-1 gives you the list of these 20 building blocks, with their
full names, three-letter codes, and one-letter codes (the
IUPAC code, after the
International Union of Pure and Applied Chemistry committee that designed it).
Table 1-1 The 20 Amino Acids and Their Official Codes
# 1-Letter Code 3-Letter Code Name
1 A Ala Alanine
2 R Arg Arginine
3 N Asn Asparagine
4 D Asp Aspartic acid
5 C Cys Cysteine
6 Q Gln Glutamine
7 E Glu Glutamic acid
8 G Gly Glycine
9 H His Histidine
10 I Ile Isoleucine
11 L Leu Leucine
12 K Lys Lysine
13 M Met Methionine
14 F Phe Phenylalanine
15 P Pro Proline
16 S Ser Serine
17 T Thr Threonine
18 W Trp Tryptophan
19 Y Tyr Tyrosine
20 V Val Valine
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Chapter 1: Finding Out What Bioinformatics Can Do for You
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