Antimicrobial

Alloferon

13 residues · 1265 Da · 90 atoms

Thirteen residues, six of them glycine and four histidine, which makes the backbone unusually flexible. An immune signal rather than a membrane-disrupting peptide, unlike the rest of this group.

Reference entry · not stocked

Aurein 1.2

13 residues · 1480 Da · 105 atoms

Thirteen residues forming a short helix with a clear split between its charged and greasy faces.

Reference entry · not stocked

Bactenecin

12 residues · 1484 Da · 102 atoms

Twelve residues with cysteines at three and eleven joined by a disulfide, closing a loop with a single residue hanging off each end. The smallest cyclic antimicrobial peptide from cattle.

Reference entry · not stocked

Beta-defensin 2

41 residues · 4328 Da · 299 atoms

Forty-one residues with three disulfides in a different arrangement to the alpha-defensin above. The two families are named for exactly that difference in how their bonds pair up, and both are here to show it.

Reference entry · not stocked

Buforin II

21 residues · 2435 Da · 172 atoms

Twenty-one residues cut from histone H2A, the protein that packages DNA. A proline in the middle puts a kink in the helix, which is unusual and is thought to matter.

Reference entry · not stocked

Cecropin B

35 residues · 3835 Da · 270 atoms

Thirty-five residues in two helices joined by a hinge: a charged one at the front and a hydrophobic one at the back. One of the first antimicrobial peptides ever described.

Reference entry · not stocked

Citropin 1.1

16 residues · 1615 Da · 114 atoms

Sixteen residues opening with the same glycine-leucine-phenylalanine-aspartate as aurein, which is also here. The two are close relatives.

Reference entry · not stocked

Defensin HNP-1

30 residues · 3442 Da · 238 atoms

Thirty residues held by three disulfides in a fixed pattern: first to last, and two more crossing the middle. Six cysteines out of thirty, and every one of them is bonded. The most heavily cross-linked structure in this library.

Reference entry · not stocked

Dermaseptin S1

34 residues · 3455 Da · 241 atoms

Thirty-four residues, one of the longest linear antimicrobial peptides described, forming a single continuous helix.

Reference entry · not stocked

Histatin 5

24 residues · 3036 Da · 217 atoms

Twenty-four residues from human saliva, seven of them histidine, which is what binds the metal ions it depends on. No other peptide here is so histidine-rich.

Reference entry · not stocked

Indolicidin

13 residues · 1906 Da · 139 atoms

Thirteen residues, five of which are tryptophan and three proline. That composition is extraordinary: no other peptide here is close, and the mass of indole rings makes it visually unmistakable.

Reference entry · not stocked

Lactoferricin B

25 residues · 3124 Da · 219 atoms

Twenty-five residues released from lactoferrin by digestion, closed into a large loop by a single disulfide between residues three and twenty.

Reference entry · not stocked

Magainin 2

23 residues · 2467 Da · 174 atoms

Twenty-three residues that fold into a helix with all the charged side chains on one face and all the greasy ones on the other. That split is the whole mechanism: it is what lets the helix sit in a membrane.

Reference entry · not stocked

Melittin

26 residues · 2847 Da · 201 atoms

Twenty-six residues, hydrophobic through the front and strongly basic at the tail. A proline near the middle bends the helix into two segments.

Reference entry · not stocked

Pandinin 2

24 residues · 2611 Da · 186 atoms

Twenty-four residues with a proline breaking the helix in the middle, the same architecture melittin uses.

Reference entry · not stocked

Pexiganan

Magainin 2 with more lysines

22 residues · 2477 Da · 176 atoms

Magainin redesigned with extra lysines to make it more strongly cationic. Both are in the library, and comparing them shows a natural peptide next to a deliberately engineered version of itself.

Reference entry · not stocked

Protegrin-1

18 residues · 2156 Da · 148 atoms

Eighteen residues held by two disulfides into a hairpin. Both bonds are drawn, and the chain is folded until each reaches a real bonding distance rather than having lines drawn across it.

Reference entry · not stocked

Temporin A

13 residues · 1397 Da · 99 atoms

Thirteen residues, almost entirely hydrophobic with a single arginine. One of the shortest natural antimicrobial peptides.

Reference entry · not stocked