---
title: "Lysine: research glossary | Sable Peptides"
description: "Lysine (three-letter code Lys, one-letter code K) is a basic amino acid with a primary amine on a four-carbon side chain, positively charged at neutral pH."
canonical: https://www.sablepeptides.co.uk/glossary/lysine
publisher: Sable Peptides Limited (UK company 17488610)
note: Research use only. Not for human or veterinary use.
---

Glossary

# Lysine

Lysine (three-letter code Lys, one-letter code K) is a basic amino acid with a primary amine on a four-carbon side chain, positively charged at neutral pH. Lysine increases water solubility and is a common site for attaching labels, lipids or PEG. Each lysine contributes a site for counter-ion pairing in TFA salts.

Source: [en.wikipedia.org](https://en.wikipedia.org/wiki/Lysine)

## Related terms

-   [Amino acid](/glossary/amino-acid)
-   [Counter-ion](/glossary/counter-ion)
-   [One-letter code](/glossary/one-letter-code)
-   [Solubility](/glossary/solubility)

[Back to glossary A–Z](/glossary/terms)

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