Hormonal
Insulin A-chain
The shorter of insulin's two chains
Reference entry · not stocked
69 more in HormonalIdentity
- Class
- Hormonal
- Molecular weight
- 2384 Da
- Residues
- 21
- Heavy atoms
- 163
- Reference slug
- insulin-a-chain
These are published properties of the molecule, given for identification. Values we cannot confirm are omitted rather than estimated. What these terms mean.
What this compound is
Twenty-one residues carrying four cysteines. In whole insulin two of them bridge to the B-chain and one pair closes an internal loop; shown alone here, so the sulphurs are drawn free.
Sequence
| 1 | GIVEQCCTSI CSLYQLENYC N |
|---|
- Three-letter code
- Gly-Ile-Val-Glu-Gln-Cys-Cys-Thr-Ser-Ile-Cys-Ser-Leu-Tyr-Gln-Leu-Glu-Asn-Tyr-Cys-Asn
The one-letter code gives the amino-acid backbone. Terminal modifications, where a compound carries them, are accounted for in the molecular weight above but are not visible in the letters.
Residue composition
Counted directly from the sequence above. Insulin A-chain is built from 11 of the twenty standard amino acids across 21 positions.
By residue
| Residue | Code | Count | Share |
|---|---|---|---|
| Cysteine | C · Cys | 4 | 19% |
| Glutamic acid | E · Glu | 2 | 9.5% |
| Isoleucine | I · Ile | 2 | 9.5% |
| Leucine | L · Leu | 2 | 9.5% |
| Asparagine | N · Asn | 2 | 9.5% |
| Glutamine | Q · Gln | 2 | 9.5% |
| Serine | S · Ser | 2 | 9.5% |
| Tyrosine | Y · Tyr | 2 | 9.5% |
| Glycine | G · Gly | 1 | 4.8% |
| Threonine | T · Thr | 1 | 4.8% |
| Valine | V · Val | 1 | 4.8% |
By side-chain class
Nonpolar, aliphatic
6 · 28.6%
G I L V
Aromatic
2 · 9.5%
Y
Polar, uncharged
11 · 52.4%
C N Q S T
Negatively charged
2 · 9.5%
E
Side-chain classes follow the standard grouping of the twenty proteinogenic amino acids. Composition is arithmetic over the published sequence and says nothing about how the molecule behaves.
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Reference entry
This is a reference entry. Sequence, residue count, molecular weight and atom count are published properties of the molecule, given for identification. Nothing on this page describes an application, benefit, dose, route or outcome, and nothing here should be read as an offer to supply or as guidance for use in a person or an animal. Materials sold by PepXtide are for laboratory research use only, are not for human or animal consumption, and have not been evaluated by the FDA.