Four novel antimicrobial peptides derived from human C8α-MACPF.

Area of Science:

• Biochemistry
• Immunology
• Microbiology

Background:

• Antimicrobial peptides (AMPs) are crucial in innate immunity, exhibiting broad-spectrum antimicrobial activity.
• The complement system, particularly C8α, is a potential source for novel AMP discovery.

Purpose of the Study:

• To identify and characterize novel antimicrobial peptides from the C8α complement component.
• To evaluate the antimicrobial and hemolytic activities of the identified peptides.

Main Methods:

• Bioinformatics analysis was employed to identify potential AMPs within the C8α complement component.
• Gene cloning, protein expression (fusion with EDDIE), and peptide synthesis were performed.
• Antimicrobial activity assays against various bacteria and hemolytic assays were conducted.

Main Results:

• Six potential novel peptides (A1, C1, A2, A3, C2, A4) were identified in C8α.
• Peptides A1, A2, A3, and A4 exhibited significant antimicrobial activity against tested bacteria.
• Peptides C1 and C2 showed no antimicrobial activity.
• Peptides A1-A4 displayed no hemolytic activity at concentrations up to 500 μg/ml over 3 hours.

Conclusions:

• A1, A2, A3, and A4 are novel antimicrobial peptides derived from the human C8α complement component.
• These peptides possess potent antimicrobial properties without causing hemolysis, indicating their potential as therapeutic agents.