11. TPCK is chosen for the chemical labelling of active histidine in enzyme analysis. 12. This pocket contains a histidine buried at the bottom where domain 2 attaches. 13. Two histidine residues from each subunit coordinate the haem. 14. Histidine kinases usually have an N-terminal superfamily.15. The imidazole nitrogen of a histidine side-chain is a common ligand. 16. S100A8 histidine residues are coloured grey, S100A9 histidine residues are coloured purple. 17. S100A8 histidine residues are coloured grey, S100A9 histidine residues are coloured purple. 18. The CHAP domain contains two invariant residues, a cysteine and a histidine . 19. One of the histidine residues is electrostatically bound to a negatively charged phosphate. 20. The second, histidine , they will inject.
