Gastrointestinal Endogenous Proteins as a Source of Bioactive Peptides - An In Silico Study

Abstract

Dietary proteins are known to contain bioactive peptides that are released during digestion. Endogenous proteins secreted into the gastrointestinal tract represent a quantitatively greater supply of protein to the gut lumen than those of dietary origin. Many of these endogenous proteins are digested in the gastrointestinal tract but the possibility that these are also a source of bioactive peptides has not been considered. An in silico prediction method was used to test if bioactive peptides could be derived from the gastrointestinal digestion of gut endogenous proteins. Twenty six gut endogenous proteins and seven dietary proteins were evaluated. The peptides present after gastric and intestinal digestion were predicted based on the amino acid sequence of the proteins and the known specificities of the major gastrointestinal proteases. The predicted resultant peptides possessing amino acid sequences identical to those of known bioactive peptides were identified. After gastrointestinal digestion (based on the in silico simulation), the total number of bioactive peptides predicted to be released ranged from 1 (gliadin) to 55 (myosin) for the selected dietary proteins and from 1 (secretin) to 39 (mucin-5AC) for the selected gut endogenous proteins. Within the intact proteins and after simulated gastrointestinal digestion, angiotensin converting enzyme (ACE)-inhibitory peptide sequences were the most frequently observed in both the dietary and endogenous proteins. Among the dietary proteins, after in silico simulated gastrointestinal digestion, myosin was found to have the highest number of ACE-inhibitory peptide sequences (49 peptides), while for the gut endogenous proteins, mucin-5AC had the greatest number of ACE-inhibitory peptide sequences (38 peptides). Gut endogenous proteins may be an important source of bioactive peptides in the gut particularly since gut endogenous proteins represent a quantitatively large and consistent source of protein.

Identification of snake bradykinin-potentiating peptides (BPPs)-simile sequences in rat brain – Potential BPP-like precursor protein?

“…It is well know that the BK action is dependent of its binding and activation of the BK B2 receptor, which triggers intracellular signaling through G-protein activation and consequent increase in the SOD expression [63,64], which could be then the source for an increased release of these putative peptides. This suggestion is in line with the recent scientific discovery trend suggesting the importance of the production of bioactive peptides derived from recycling and/or metabolism of proteins after their primary function [65].…”

Bioactive peptides derived from bovine and porcine co-products: A review

“…The use of online databases and in silico analysis for the development of novel bioactive peptides is becoming more and more common. Online tools such as BIOPEP have been repeatedly used for bioactive peptide generation over the last couple of years (Dave, Montoya, Rutherfurd, & Moughan, ; Dellafiora et al, ; Fu et al, ; Gangopadhyay et al, ; Jin, Yan, Yu, & Qi, ; Lafarga, O'Connor, & Hayes, , Lafarga et al, ; Lin, Han, Lin, & Hou, ; Zhu et al, ). BIOPEP, available at http://www.uwm.edu.pl/biochemia/index.php/pl/biopep, consists of a database of bioactive proteins and peptides, and permits the user to use a number of tools for the evaluation of proteins.…”

Peptides Derived from Foods as Supportive Diet Components in the Prevention of Metabolic Syndrome

“…Peptides with diversified bioactivities were discovered in all sources of food proteins, that is, milk, meat, eggs, a variety of plants, and so on. Examples of peptide MSyn‐biological activities include among others antihypertensive, antioxidative, antiobesity, antidiabetic, and cholesterol level reducing effects (Dave and others ). The beneficial role of food proteins in MSyn prevention and treatment was recently reviewed by Miglani and Bains ().…”