Histidine (siok-siá: His / H), sī chi̍t chióng an-ki-sng, R group ū ke̍k-sèng, toà tiong-sèng tiān. Jîn-thé bô-hoat-tō ka-tī ha̍p-sêng chit khoán an-ki-sng.

L-histidine.