Amacidos Nemotecnia
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E-mail address: vmezl@uottawa.ca (V.A. Mezl).
Biochemistry and Molecular Biology Education 29 (2001) 66}70
The AAA amino acid list a mnemonic derivation of the structures and
properties of the amino acids
Vasek A. Mezl
Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa,
Ont. Canada, K1H 8M5
Abstract
A rhymed presentation of the amino acids, consisting of one line per amino acid, gives the structures of the amino acids, their
nomenclature, abbreviations, pKs, basic chemistry, dietary requirements and the characteristics of the peptide bond. 2001
IUBMB. Published by Elsevier Science Ltd. All rights reserved.
1. Introduction
Almost all the life sciences at some point involve the
amino acids and in day-to-day lab work one often needs
semi-quantitative amino acid data that cannot be derived
from a recollection of general structures. While most
biochemistry courses cover these compounds, the wealth
of information and the only occasional need for it means
that little is retained over the long term.
Since rhymed jingles and relationships are remembered
over long periods, a rhymed presentation of the
amino acids has been devised that not only allows one to
learn and retain the structure of the amino acids, but this
mnemonic also provides information about the amino
acids and their relationship to other body components.
The order in which these amino acids are presented,
referred to as the AAA amino acid list, can be used to
derive key metabolic relationships and several lists of
numerical data related to the amino acids. This article
presents the mnemonic and shows how to use the imagery
raised by the words to derive the structures and
some basic chemical properties.
2. Instructions
In the mnemonic, the names of amino acids are in italic
type and the three letter abbreviations are double underlined.
The one letter abbreviations are in bold type; for
the "rst 11 amino acids they are the "rst letter of the
name and for the rest of the list they are the "rst letter of
each line. Essential amino acids are identi"ed by lines
containing the word give or get (underlined in the text);
one has to give them in the diet or get them in the diet for
normal health. Vertical spacing divides the text into
sections that are used for the derivation of the structures
(endnotes), for the presentation of metabolic relationships
(article in preparation), for the generation of numerical
data (see Section 1) and for the rapid retrieval of
speci"c information about an amino acid (Section 4). The
number of words in each line is equal to the number of
carbons in each amino acid. This feature can be used to
verify several structures and for quickly calculating molecular
weights and other characteristics. Other topics
that can be derived from these lines are underlined in the
detailed explanations provided as endnotes. Fig. 1 shows
the structures of the amino acids in the order in which
they are developed using bold type to highlight the new
structural element that is added at each line.
1470-8175/01/$20.00 2001 IUBMB. Published by Elsevier Science Ltd. All rights reserved.
PII: S 1 4 7 0 - 8 1 7 5 ( 0 1 ) 0 0 0 1 3 - 3
3. The AAA mnemonic
AminoP, Acid, Alpha hydrogen;
All three on one carbon. [1]
When my forearm comes from the end and my "ngers are
AAA;
-D-sugars are my right hand, amino acids are a Left
hand away. [2]
Glycine's symmetrical; [3]
Alanine's methyl's typical. [4]
Alcohol addition's Serine;
Another methyl gives TThreonine. [5]
Twice methylated alanine gives Valine;
but stretched homovaline unfortunately gives Leucine;
[6]
Isoleucine gives another rare logical scoop; [7]
Proline's envelope freezes amino group. [8]
Sensitive sulfhydryl's Cysteine; [9]
Homocysteine methylation continuously gives
Methionine. [10]
Histidine's two nitrogen twingling imidazole star; [11]
Without its closest nitrogen, buds a benzene, giving
Trypptophan's indole handlebar. [12]
For Phenylalanine we get a weak logical scoop;
Yet ¹yrosine's just phenylalanine with A para alcohol
group. [13]
Dicarboxyl means negative Aspartic; [14]
Not amide, Asparagine's Biotypic; [15]
Extra methylene means Glutamic's homoaspartic;
Quasi homoasparagine, Glutamine's still Zwitterionic.
[16]
Key six aliphatic amine gives Lysine; [17]
Resonant guanidino on "ve begets Arginine. [18]
4. One line summary
For the rapid recall of the order or of a speci"c section
of the AAA list, a possibly life saving phrase sequentially
gives the "rst word (in italics) or the idea (underlined
below) of each section: `Glass-in Alcohol Twice: Su!er His
Negative Charges!a On the one hand, this line warns that
if one drinks two alcoholic drinks before driving, one will
be charged with driving under the in#uence of alcohol in
North America and on the other hand it recalls the order
of the various sections if one interprets suwer as sulphur,
negative as the charge on the R group and charges as the
other possible charge on the R group. Twice identi"es
the "rst section that is twice as long as most sections and
one can note that such a four line section is then found
twice more. This summary presents the amino acids as
seven groups based on the characteristics of their side
chains: small, alcohol containing, aliphatic, sulfur containing,
rings with double bonds, acids (and their amides)
and basic side chains. The lecturer should present these
groups by using the "ngers of both hands to list the
amino acid pairs. Students should be encouraged to
summarize the amino acids on their "ngers in this manner
as this will prevent them from forgetting a category of
amino acids.
5. Deriving the peptide bond from the AAA mnemonic
One mispronunciation and one word replacement
change the de"nition of an amino acid into a line that
describes the peptide bond:
...