Computational Screening of Microalgae and Cyanobacteria RuBisCO as Potential Precursors for Bioactive Peptides

Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is a critical enzyme found in plants and autotrophic organisms such as microalgae and cyanobacteria. This study conducts an in silico evaluation to identify RuBisCO proteins from these organisms as potential sources of bioactive peptides. Using the BIOPEP server and database, fourteen RuBisCO sequences from microalgae and cyanobacteria were analyzed for their potential to release bioactive peptides through selected proteolytic enzymes. The study employed tools to assess biological activity, enzyme action, and active peptide calculations to determine the frequency and efficacy of peptide release. ProtParam was used to compute the physicochemical parameters of the selected sequences. Among the analyzed proteins, Chaetoceros calcitrans showed promise for DPP-IV inhibiting peptides, Chlorella pyrenoidosa for ACE inhibition, and Aphanizomenon flos-aquae for antioxidative, ubiquitin-activating, and antiamnestic activities. The high content of glycine and proline in Aphanizomenon flos-aquae, Dunaliella salina, Chlorella pyrenoidosa, and Chlorella vulgaris is linked to a higher occurrence of bioactive fragments. Enzymes like papain and proteinase K released more biologically active fragments compared to bromelain and chymotrypsin. These findings suggest that microalgal and cyanobacterial RuBisCO could be viable alternative sources of bioactive peptide-based nutraceuticals for human consumption.