Lab
Peptide Sky
Every star is a peptide. The brighter it shines, the more people look it up.
Lab
Every star is a peptide. The brighter it shines, the more people look it up.
A peptide is a short chain of amino acids, the building blocks of every protein in your body. Each star here is one.
GLP-1s and their relatives
Most of these copy hormones your body releases after a meal, the ones that help control blood sugar and appetite.
A fatty tail on one lysine grips albumin in the blood, which is why it lasts about a week.
It switches on three receptors at once: GIP, GLP-1 and glucagon. In each one it sits as a single unbroken spiral.
Built on the gut hormone GIP, it switches on both the GIP and GLP-1 receptors. A 20-carbon fatty tail holds it to albumin for about five days.
Nearly the same chain as semaglutide, with a plain 16-carbon fat that holds it to albumin for about half a day, not a week.
A copy of amylin, a fullness hormone released with insulin, with six amino acids swapped so it can't clump into fibres, and a fatty tail on its front end.
Two GLP-1 chains joined to an antibody stump, 275 amino acids each: too big and folded to draw as one chain here.
Its second amino acid isn't one of the usual twenty: a small four-carbon ring that keeps enzymes from cutting the chain there.
The last fifteen amino acids of growth hormone with a tyrosine added to the front, and a sulfur bridge tying its two cysteines into a small loop.
Built on oxyntomodulin, a gut hormone that works on two receptors at once, with a 20-carbon fatty tail that keeps it in the blood for about a week.
The last sixteen amino acids of human growth hormone, with a sulfur bridge closing the final loop. It differs from AOD-9604 by one amino acid at the front, and vials sold under this name usually hold AOD-9604.
Instead of a fatty tail it carries a sugar with a long fatty arm, and a bond stitched between two of its own amino acids holds the middle of the chain in its spiral.
Healing and recovery
Peptides people use for healing and recovery. Many are pieces of proteins your own body makes.
Fifteen amino acids with three prolines side by side near the front. Its discoverers describe it as part of a protein found in human gastric juice; that protein has never been sequenced.
Seven amino acids: the exact stretch, 17 to 23, that the much longer thymosin beta-4 uses to grip actin, with an acetyl cap on its front.
Twenty-eight amino acids that become one long spiral the moment they dock into their receptor, with an amide capping the tail.
A floppy 43-amino-acid chain with no fixed shape of its own. It snaps into two short spirals only when it wraps around a building block of actin.
The last three amino acids of alpha-MSH, the hormone that darkens skin: the tail end, used on its own.
The first 28 amino acids of a much longer protein that lives in the cell nucleus, with an acetyl cap on the front. It stiffens into a spiral only when it touches a membrane.
Eight amino acids with not one charged side chain among them, which makes it one of the plainest molecules in the sky.
Eleven amino acids assembled from the water-facing side of one helix of erythropoietin. Its first amino acid has bitten its own tail into a ring, so that end carries no free amine.
Thirty-seven amino acids that curl into a bent spiral lying flat on a bacterial membrane, with the greasy side chains on one face and the charged ones on the other.
Copper and the melanocortins
A copper-carrying peptide, and copies of the hormone that darkens your skin in the sun.
Three amino acids holding one copper ion with three nitrogen atoms: glycine's front end, the link to histidine, and histidine's ring.
The same seven-amino-acid ring as Melanotan II. The only difference is its tail end: a plain acid where Melanotan II has an amide.
A bond between the side chains of its 2nd and 7th amino acids closes it into a ring.
The skin's own tanning hormone, alpha-MSH, with two of its 13 amino acids swapped so it survives the enzymes in blood.
Signals from the brain
Copies of signals your brain sends out to the rest of your body.
A sulfur-sulfur bond joins its 1st and 6th amino acids, closing six of its nine into a ring with a short tail.
The last ten amino acids of a 54-amino-acid hormone, ending in the Arg-Phe tip its receptor recognises.
Both ends are capped: the first amino acid curls into a small ring and the last ends in an amide. Inside its receptor it folds into a U.
Focus, calm and sleep
Short peptides people use for focus, calm and sleep.
Its first four amino acids are a piece of the stress hormone ACTH, with a sturdy Pro-Gly-Pro tail added to the end.
Its first four amino acids are tuftsin, a small piece of antibodies, and the last three (Pro-Gly-Pro) were added to help it hold up in the body.
Not quite a peptide: only two of its parts are true amino acids (tyrosine and isoleucine), with carbon-chain caps on both ends.
Its nine amino acids match no known family of peptides, and no gene that makes it has been found.
Not one molecule: a mix of small peptides and free amino acids made from pig brain proteins.
Semax with both ends capped: an acetyl group on the front and an amide on the back.
Four of its five parts are copied from the nerve-supporting protein CNTF, and the fifth is a rigid adamantane cage that makes it sturdier.
Mitochondria and ageing
Peptides people use for healthy ageing. Several are tied to mitochondria, the tiny power plants in your cells.
Its first link is unusual: the glutamate holds the cysteine with its side arm, not the end that amino acids normally use. That is why it survives the gut's ordinary enzymes.
Four amino acids, built to match the amino-acid makeup of an extract of the pineal gland.
Its 16 amino acids are written inside a mitochondrial gene whose main job is to build a piece of the ribosome's RNA.
Three amino acids: glutamate, aspartate, arginine. The shortest chain in the sky.
Four building blocks: a mirror-image arginine the body never builds, then a tyrosine carrying two extra methyl groups.
Every amino acid is a mirror image of the natural kind and the order is written backwards, so the side chains sit where they need to while the body's enzymes no longer recognise the chain.
Like MOTS-c, its 24 amino acids are written inside a mitochondrial gene for ribosome RNA, and the chain takes a spiral shape only outside water.
The growth hormone axis
Peptides that tell your body to release more of its own growth hormone, plus growth hormone and its relatives.
Four long spirals folded back on each other and pinned by two sulfur bridges: 191 amino acids, far bigger than the peptides around it.
The body's whole growth-hormone-releasing hormone, all 44 amino acids, with a small six-carbon cap on its front that keeps enzymes off it.
The first 29 amino acids of the body's own growth-hormone-releasing hormone: the shortest piece that still works.
The same chain plus one lysine carrying a small reactive ring that bonds to albumin in the blood, so it lasts days instead of minutes.
Sermorelin with four amino acids swapped. The second is flipped to its mirror image, which stops the enzyme that would cut it in two.
Five building blocks, two of them mirror-image amino acids, designed by leaving the middle out of an older growth-hormone peptide.
The 344 counts a 29-amino-acid leader that cells cut off, so the protein in blood has 315 amino acids, folded and stapled by 18 sulfur bridges.
Human IGF-1 with one amino acid swapped and a 13-amino-acid extension on its front, so the carrier proteins in the blood can't hold on to it.
Designed from met-enkephalin, a natural brain peptide, yet it fills the same receptor pocket as the hunger hormone ghrelin.
Half of its six amino acids are mirror-image forms, and one carries a double-ring naphthalene group no natural amino acid has.
The 24-amino-acid tail of a growth factor muscles make more of after hard exercise. Its PEG chain isn't drawn: no source gives its size or where it attaches.
GHRP-6 with one extra methyl group on its second amino acid, which makes it chemically more stable.
GHK-Cu + KPV + BPC-157 + TB-500
GHK-Cu + BPC-157 + TB-500
CJC-1295 (no DAC) + Ipamorelin
Cagrilintide + Semaglutide
BPC-157 + TB-500
Semax + Selank + Dihexa
MOTS-c + Epitalon + SS-31
Nothing here is invented. Every part comes from published science, and every star lists its sources.
Every star is a peptide people use or study. The more its English Wikipedia page is read (the last 4 weeks), the brighter it shines.
Every bead is one amino acid, in the order published for that peptide: its drug label, its patent or the paper that made it.
Where scientists have measured a peptide's shape, you see that shape: 18 of the 51 here, from the Protein Data Bank. The rest have no one fixed shape to measure, so they are drawn as flexible chains.
Where a peptide has a gene, the DNA you see is that gene, letter for letter from the gene records, and every three letters were checked against the bead they spell.
Inside a bead, every atom sits where the Protein Data Bank's chemical dictionary puts it.
Each star's Sources lists the records behind it: 608 links in all.
Drawn from published sequences and structures. For learning, not medical advice.