essential amino acid
Let an agent explain essential amino acids and which they are, relay biochemistry, nutrition and protein quality from scientific references, describe dietary sources in general terms, and distinguish essential from conditionally essential and non-essential amino acids and from the specific threonine isomers listed as aliases.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent explain essential amino acids and which they are, relay biochemistry, nutrition and protein quality from scientific references, describe dietary sources in general terms, and distinguish essential from conditionally essential and non-essential amino acids and from the specific threonine isomers listed as aliases.
An amino acid that the human body cannot synthesise and must obtain from food, comprising histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine, with threonine also known systematically as 2-amino-3-hydroxybutanoic acid and occurring in stereoisomers such as L-threonine, D-threonine and allo-threonine and labelled forms used in research; essential amino acids are the basis of protein quality assessment in nutrition.
What it is for: Not applicable; a class of nutrients.
It can be explain the class; relay biochemistry and nutrition; describe dietary sources; distinguish related categories.
Distinguishing features
Not synthesised by humans
Dietary requirement
Protein quality basis
Species-dependent
What it looks like
Not a visible object; molecules in proteins.
Physical character
essential amino acids in humans: 9 count
threonine formula: C4H9NO3 formula
protein quality score: DIAAS note - FAO 2013
How it is recognised
Amino acid that must come from the diet
Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine
Non-essential amino acids are synthesised; conditionally essential ones are needed in some states
Related models
is a kind of - in registry terms
is exemplified by - named in the aliases
is contrasted with - synthesised by the body
is assessed by - scores such as DIAAS
In practice
Families and kinds
branched-chain amino acids leucine, isoleucine and valine
aromatic amino acids phenylalanine and tryptophan
sulphur-containing methionine
lysine, threonine and histidine
threonine stereoisomers and labelled forms
conditionally essential amino acids
Identifiers
ChEBI CHEBI:33709 amino acid class
CAS 72-19-5 L-threonine
Standards and regulation
FAO and WHO protein and amino acid requirements
Food labelling rules
Feed regulations for amino acid supplements
Failure modes and hazards
Agents giving personal nutrition advice
Confusing essential and non-essential lists across species
Registry aliases naming isomers of one acid
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.essential-amino-acid
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Understand What essential amino acids are.
Science.
Definition
Definition.
Definition
Definition.
- What are essential amino acids, and how do they differ from conditionally essential and non-essential ones? definition
- Is the question about the class, a specific acid, nutrition or a personal diet? boundary
List
The nine.
List
List.
- What are the nine essential amino acids, and what does each do? definition
- Which entry fits the specific amino acid? action
Nutrition Nutrition.
Science.
Sources
Dietary sources.
Sources
Sources.
- Which foods provide complete proteins, and how do plant proteins combine, in general terms? provenance
- Is the user asking for personal dietary advice, which needs a professional? boundary
Quality
Protein quality.
Quality
Quality.
- How do PDCAAS and DIAAS assess protein quality? provenance
- Which references are standard? provenance
Chemistry Chemistry.
Science.
Threonine
Threonine.
Threonine
Threonine.
- What is threonine, and what are its L, D and allo stereoisomers and labelled forms? provenance
- Which sources are cited? provenance
Metabolism
Metabolism.
Metabolism
Metabolism.
- How are essential amino acids absorbed, used and degraded? provenance
- Which entry fits amino acid metabolism? action
Context Health and history.
Context.
Health
Deficiency and disease.
Health
Health.
- What happens in amino acid deficiency and in disorders such as phenylketonuria, in general terms? provenance
- Which entry fits protein-energy malnutrition? action
History
History.
History
History.
- How were essential amino acids identified by William Rose and others? provenance
- Which entry fits the history of nutrition science? action
What the second pass must settle
- Should threonine and the branched-chain amino acids be separate primary entries?
- How should nutrition references be linked?
- The registry entry has merged aliases naming threonine isomers; should they be split off?