From the Guidelines
A complete list of all dipeptides is not feasible due to the numerous possible combinations of the 20 standard amino acids, resulting in approximately 400 possible dipeptides. Dipeptides are molecules consisting of two amino acids joined by a peptide bond, and they have various biological functions and applications. Some notable examples include carnosine (beta-alanine-histidine), anserine (beta-alanine-1-methylhistidine), and aspartame (aspartic acid-phenylalanine methyl ester) 1. These dipeptides have been studied for their potential benefits, such as glutamine dipeptide, which has been reviewed in several studies for its effects on morbidity and outcome in surgical patients 1.
- Notable dipeptides include:
- Carnosine (beta-alanine-histidine), which acts as an antioxidant in muscle tissue
- Anserine (beta-alanine-1-methylhistidine), which has similar properties and is found in birds and fish
- Aspartame (aspartic acid-phenylalanine methyl ester), a common artificial sweetener
- Dipeptides can be naturally occurring in foods and tissues or synthesized for pharmaceutical, research, or food additive purposes
- They represent an important class of biomolecules that serve as building blocks for larger peptides and proteins, and some have specific biological activities including buffering, antioxidant properties, and taste modification 1.
From the Research
Dipeptides Overview
- Dipeptides are compounds consisting of two amino acids linked by a peptide bond.
- They can be found in various forms and have different biological activities.
Examples of Dipeptides
- Carnosine (β-alanyl-L-histidine) is a histidine-containing dipeptide found in excitable tissues such as the nervous system and skeletal muscle 2.
- Homocarnosine (γ-amino-butyryl-histidine), balenine (β-alanyl-L-3-methylhistidine), and anserine (β-alanyl-L-1-methylhistidine) are also histidine-containing dipeptides 2.
- Cyclo(L-Leu-L-Pro) and cyclo(L-Pro-L-Pro) are volatile cyclic dipeptides found in terrestrial vertebrates 3.
Synthesis and Identification of Dipeptides
- Dipeptides can be synthesized by conventional means or derived from polypeptides digested with dipeptidyl aminopeptidase 4.
- Trimethylsilylation of dipeptides can be used for identification and separation using gas chromatography and mass spectrometry 4.
Biological Activities of Dipeptides
- Carnosine and its derivatives have anti-aging, antioxidant, membrane protective, metal ion chelating, buffering, anti-glycation/transglycating activities 5.
- Carnosine supplementation has been shown to have beneficial effects in preventing sarcopenia, preserving cognitive abilities, and improving neurodegenerative disorders 6.
- Cyclo(L-Pro-L-Pro) has been found to have a potential semiochemical role in male intra-specific communication in terrestrial vertebrates 3.