FHI Programme Identifies New Bioactive Peptides in Milk Proteins

The bioinformatics team uses a combination of evolutionary principles and cues in amino acid sequences to detect potential bioactive peptides within the milk proteins.

24 May 2010 --- Over 30 new bioactive milk peptides have been identified by Food for Health Ireland’s (FHI’s) bioinformatics work package at University College Dublin. Part of FHI’s intelligent milk mining programme, the latest breakthrough will enable researchers to focus on the most meaningful biological elements of milk whey and casein proteins, ultimately benefiting the development of new functional foods.

The bioinformatics team uses a combination of evolutionary principles and cues in amino acid sequences to detect potential bioactive peptides within the milk proteins. Bioactive peptides are among many elements in food which can benefit and enhance human health, and have captured the attention and imagination of the research community in recent years.

Bioactive peptides are embedded in the protein sequence where they remain inactive until released from the full protein by appropriate enzymes. An advantage of the bioinformatics, computer based strategy is that it can first rule out any known bioactive sequences in the published literature, so that investigations can focus on detecting novel regions of the proteins. Bioinformatics enables a systematic and intelligent approach to leverage existing knowledge and direct the generation of new healthy ingredients.

Initially, researchers compared bovine, human and other mammalian milk proteins to detect regions that are more conserved in evolution than expected. Conserved regions in a protein are those that have remained constant through evolutionary changes and are often required for basic cellular function and interaction. The next stage of the programme involved searching for patterns of amino acid composition that are characteristic of known bioactive peptides. Indeed, many peptides share common features, such as their amino acid composition. The bioinformatics team then narrowed down the focus to sets of regions that share similar amino acid composition to known beneficial peptides. The 30 predicted novel peptides are currently being synthesised and tested by FHI.

Dr Nora Khaldi, leader of FHI’s bioinformatics work package, comments: “Unlike any other food, milk has had the chance to co-evolve with mammals for over 200 million years. In other words, milk has adapted to the different needs of the diverse array of mammals. The goal of any species is to maintain its fitness and growth - which is a direct result of the current and future health of the offspring. Because of milk’s adaptation to the species needs, it holds the key to those elements that increase the offspring’s health. It is these beneficial features that we are now isolating from milk proteins. This novel approach focuses investigation on the important regions of milk proteins and can thus bring major benefits to future functional foods”