Identification of Antimicrobial Peptides from the Microalgae Tetraselmis suecica (Kylin) Butcher and Bactericidal Activity Improvement

• Published in: Marine drugs 2019-08, Vol.17 (8), p.453
• Main Authors: Guzmán, Fanny, Wong, Genezareth, Román, Tanya, Cárdenas, Constanza, Alvárez, Claudio, Schmitt, Paulina, Albericio, Fernando, Rojas, Verónica
• Format: Article
• Language: English
• Subjects: active ingredients; Alanine; alanine scan; Algae; alpha helical secondary structure; Amino Acid Sequence; Amino acids; Analogs; Antibacterial activity; antibacterial properties; antibiotic resistance; Antibiotics; Antimicrobial agents; Antimicrobial Cationic Peptides - chemistry; Antimicrobial Cationic Peptides - isolation & purification; Antimicrobial Cationic Peptides - pharmacology; Antimicrobial peptides; Aquatic environment; Aquatic fungi; Aquatic microorganisms; Aquatic Organisms - chemistry; Bacteria; Bacteria - drug effects; Bacterial infections; Bactericidal activity; Chlorophyta - chemistry; Chromatography; Cytotoxicity; Disease resistance; E coli; Enzymes; Fatty acids; Fungi; Localization; Lysine; lysine analogs; Marine microorganisms; Mass spectrometry; microalga; Microalgae; Microalgae - chemistry; Microbial Sensitivity Tests; Microorganisms; Pathogenic bacteria; Peptides; Peptides - chemistry; Peptides - isolation & purification; Peptides - pharmacology; Phytoplankton; Protein structure; Protein Structure, Secondary; Scientific imaging; Secondary structure; Staphylococcus infections; Synthetic peptides; Tetraselmis suecica; virulent strains; Viruses
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md17080453

The outburst of microbial resistance to antibiotics creates the need for new sources of active compounds for the treatment of pathogenic microorganisms. Marine microalgae are of particular interest in this context because they have developed tolerance and defense strategies to resist the exposure to pathogenic bacteria, viruses, and fungi in the aquatic environment. Although antimicrobial activities have been reported for some microalgae, natural algal bioactive peptides have not been described yet. In this work, acid extracts from the microalga with antibacterial activity were analyzed, and de novo sequences of peptides were determined. Synthetic peptides and their alanine and lysine analogs allowed identifying key residues and increasing their antibacterial activity. Additionally, it was determined that the localization of positive charges within the peptide sequence influences the secondary structure with tendency to form an alpha helical structure.