1. An amino acid that is one of the 20 standard amino acids found in proteins; essential for growth and development, especially in infants.
Usage: biochemistry; Also spelled histidin in some contexts, though histidine is the standard spelling.

Examples

• Histidine is classified as a semi-essential amino acid because the body can produce it, but dietary sources are still important.
• The protein structure depends on the proper incorporation of histidine at specific positions.
• Histidine plays a crucial role in enzyme function and metal ion binding.
• Infants require adequate histidine intake because their bodies cannot synthesize enough of it.
• Many foods rich in protein, such as chicken and cheese, contain significant amounts of histidine.