Title:Rubiscolins - Highly Potent Peptides Derived from Plant Proteins
Volume: 18
Issue: 2
Author(s): Renata Perlikowska*Anna Janecka
Affiliation:
- Department of Biomolecular Chemistry, Faculty of Medicine, Medical University of Lodz, 92-215 Lodz,Poland
Keywords:
RuBisCo, opioid peptides, δ opioid receptor, structure-activity relationship, antinociception, food intake.
Abstract: Rubiscolins are two naturally occurring, linear peptides, isolated from the pepsin digests of
D-ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) from spinach leaves. Their sequences
are as follows: Tyr-Pro-Leu-Asp-Leu (YPLDL, rubiscolin-5) and Tyr-Pro-Leu-Asp-Leu-Phe (YPLDLF,
rubiscolin-6, also known as rubixyl). Though their structure does not resemble typical opioid peptides,
rubiscolins were found to exhibit high affinity and selectivity for the delta opioid receptor and an antinociceptive
effect in mice after oral administration. Moreover, orally administered rubiscolin-6 was
shown to possess orexigenic, anxiolytic-like, and memory-enhancing activities in mice. This review
summarizes various biological activities of rubiscolins in mammalian organism and recent developments
on the structure-activity relationship of rubiscolin analogs, aimed at improving their pharmacological
properties. Naturally occurring substances, such as rubiscolins, may provide a rational and powerful
approach in the design of new therapeutics or functional foods.