Abstract
Antimicrobial peptide (AMP) peptide-based lead compound has become interesting target in developing new antibiotics. AMP is possibly generated through the digestion of protein. The protein of castor (Ricinus communis) seed is characterized as a ribosome-inactivating protein (RIP) that can be a source of AMP. The objectives of this research are to identify antibacterial peptides from Ricinus communis seed protein hydrolysate. The seed protein was isolated using sodium dodecyl sulfate and subsequently digested using trypsin. The hydrolysate was fractionated using a strong cation exchange chromatography system, and the resulting fractions were tested for antibacterial activity. The peptides present in the active fraction were identified using high-resolution mass spectrometry. As the result, the pH 4 and pH 5 fractions of the elution buffer indicated antibacterial activity, with the pH 4 fraction of the hydrolysate having high activity against both gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria. Three peptides that have the sequences EESETVGQR, GQSTGTGQQER, and LDALEPDNR could be responsible for the activity of the pH 4 fraction. The antibacterial activity of these peptides, which is due to their ionic properties and secondary structure, supports the disruption of the bacterial cell membrane. It can be concluded that Ricinus communis seed protein hydrolysate contains peptides with sequence EESETVGQR, GQSTGTGQQER, and LDALEPDNR that potent to be used as AMP lead compounds
Highlights
The treatment of bacterial infections and diseases using antibiotics is currently facing problems because of bacterial resistance to existing antibiotics
This study aimed to reveal the antibacterial activity of peptides obtained from the tryptic hydrolysis of castor seed protein
A higher concentration of sodium dodecyl sulfate (SDS) could lead to ion suppression that interferes with ion exchange fractionation and MS analysis of the peptides (Scheerlinck et al, 2015)
Summary
The treatment of bacterial infections and diseases using antibiotics is currently facing problems because of bacterial resistance to existing antibiotics. Peptides are interesting targets to study for their potential as antibacterial compounds because their structures vary depending on the amino acid sequence and peptide length. Some natural peptides, such as thionin (plant peptides), bombinin, and cecropin (insect peptides) have been used as the basis for the development of antibiotics. Most antibacterial peptides contain the tip of weakly loaded amino acids, such as arginine (R) and lysine (K) (Hancock et al, 2006). This phenomenon is related to the biosynthesis of antibacterial peptides, which involves the enzymatic proteolytic hydrolysis of protease against polypeptides
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
