Deprotonation of the cysteine sulfhydryl by an adjacent histidine residue is followed by nucleophilic attack of the cysteine S on the peptide carbonyl carbonyl carbon.
Histidine is metabolized into the neurotransmitter histamine which is used by the body in its response to foreign substances.
This region includes a conserved histidine followed, two residues later by a glutamate and another histidine.
If yes answer this question with YES, both histidine side chain nitrogens in all histidine side chain nitrogens in all histidines will be treated as basic.
The turn provides a hydrophobic environment for the zinc ion and the three ligating histidine residues at the catalytic centers of the enzymes.