The black mamba snake here illustrates the structure of mambaglin-1, a pain-relieving peptide found in its venom. Thick gray lines lines represent the four disulfide bonds linking Cys1–3, 2–4, 5–6, and 7–8. The N-terminus of the 57 amino acid peptide is at the head of the snake and the C-terminus at the tail. The peptide has potential as a pharmacological probe or drug lead. Image design by David Craik and drawing by Peta Harvey, University of Queensland.