Food Proteins as Precursors of Bioactive Peptides — Classification Into Families

Abstract

The Bioactive Peptides (BIOPEP) database developed at the Department of Food Biochemistry, University of Warmia and Mazury in Olsztyn was used to determine the profiles of the potential biological activity of food proteins and to classify them into families. Proteins whose amino acid sequences contained fragments with a specified activity and which were a potential source of this activity were divided into families. Among the 44 biological activities of peptides included in the BIOPEP database, 23 were selected for analysis. The number of families was diversified. The largest families were composed of proteins — precursors of antihypertensive peptides and dipeptidyl aminopeptidase IV inhibitors as well as those activating ubiquitin-mediated proteolysis and opioid ones. Only a few proteins included in the database contained in their sequences fragments with the following activities: chemotactic, binding and transporting metals and metal ions, stimulating red blood cells synthesis, inducing contractions of smooth muscles, and hemolytic. Highly numerous families were divided into five sub-families according to the value of the frequency of occurrence of fragments exhibiting given activity (A parameter).

Identification of bioactive peptides in hypoallergenic infant milk formulas by capillary electrophoresis–mass spectrometry

“…Milk proteins are precursors of many different bioactive peptides that may remain latent until being released by enzymatic proteolysis during gastrointestinal digestion or food processing [1][2][3][4][5][6][7]. Immunostimulating, antimicrobial, opioid, angiotensinconverting enzyme inhibition, mineral binding, antithrombotic, allergenic are, among others, the described bioactivities [1][2][3][4][5][6][7].…”

Milk proteins-derived bioactive peptides in dairy products: molecular, biological and methodological aspects

“…The precursors of many biological active peptides include food proteins. Food protein peptides can lower blood pressure, inhibit the activity of proline-specifi c endopeptidases, stimulate the immune system, act as opioids and opioid antagonists, contract smooth muscles, inhibit blood platelet aggregation, inhibit HIV proteinase and oxidation processes, demonstrate antibacterial and fungicidal activity and surface activity, bind ions, participate in mineral transport, determine sensory properties, improve the nutritional value of foods and control body weight [Dziuba and Darewicz 2007]. According to the current state of scientifi c knowledge, in addition to fulfi lling its basic roles, every protein can contain fragments that control life processes in various organisms [Karelin et al 1998].…”

“…The results can be used in food research, and they can support the development of new technologies for the production of special purpose foods. The main stages of research into bioactive peptides and precursor proteins include the identifi cation and selection of proteins characterised by the highest frequency of motifs with the given activity [Dziuba and Darewicz 2007], selection of enzymes that release those motifs (in silico proteolysis) [Dziuba et al 2006], verifi cation of the results of in silico proteolysis by analytical methods [Vecruysse et al 2009], peptides isolation and purifi cation [Korhonen and Pihlanto 2006] application of in vitro methods, followed by ex vivo and in vivo methods in evaluations of biological activity [Expósito andRecio 2006, Simos et al 2011], and determination of correlations between structure and function [Iwaniak 2011]. The combination of bioinformatics and chemometrics tools speeds up the screening of various peptide sources with high levels of biological activity and optimises the process of isolating (selected substrates) and identifying peptides in food products.…”

“…Food proteins and peptides are hydrolysed at different stages: ingestion, digestion and absorption [Shimizu 2004, Vermeirssen et al 2004. The exact amount of a peptide that can be released and activated during the consumption of a balanced diet remains unknown because proteolytic enzymes are characterised by varied specifi city, therefore, the range of bioactive fragments released from a precursor protein cannot be accurately predicted [Dziuba and Darewicz 2007, Dziuba et al 2006, Phelan et al 2009]. The presence of bioactive peptides in dairy products such as cheese, fermented milk and yoghurt has been reported in numerous research studies [FitzGerald et al 2004, Gagnaire 2001, Gobbetti et al 2002, Korhonen and Pihlanto 2006, Meisel et al 1997, Nakamura et al 1995, Saito et al 2000.…”

Safety of protein hydrolysates, fractions thereof and bioactive peptides in human nutrition

“…Examples are b-casomorphin (opiate activity), casein macro peptide (stimulation of release of CCK), b-casein fragments (angiotensin-I-converting enzyme inhibition), casein phosphopeptides (enhancement of mineral absorption), a-lactalbumin fragments (immune stimulation) and a wide range of antimicrobial peptides derived from caseins and whey proteins. For an extensive overview of food proteins and their bioactive amino-acid sequences, the reader is referred to Dziuba and Darewicz (2007).…”