Studies of the mechanism of an antibacterial peptide (cecropinA-magainin) on methicillin-resistant Staphylococcus aureus membranes.
As bacterial resistance becomes increasingly common, a new hybrid peptide, cecropinA-magainin (KWALSKEGPGKFLGKKKKF), has been developed that can kill a broad spectrum of bacteria without damaging human cells. The mechanism of antibacterial toxicity for the hybrid peptides is unknown. Herein, we investigate the localization of the hybrid peptide in methicillin-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentration was 64 µg/mL. The hybrid peptides could enhance the hydrophobicity of MRSA. Dye leakage experiments showed that the hybrid peptides caused dye leakage from liposomes. The hybrid peptides influenced the permeability of the outer membrane and plasma membrane of MRSA. After cecropinA-magainin treatment of MRSA, the membrane ultrastructure was damaged and the concentration of K+increased. Ultimately, the peptide destroyed the integrity of the bacterial cell membrane, allowing the dye propidium iodide to enter the cytoplasm. Therefore, the hybrid antibacterial peptide can kill MRSA.
Institute of Clinical Laboratory of Medicine of Ningxia Medical University, XingQing District, Yinchuan, Ningxia, People's Republic of China.
Longmei
L
Yu
Center of Science Technology of Medicine of Ningxia Medical University, XingQing District, Yinchuan, Ningxia, People's Republic of China.
Mingxing
M
Zhu
Institute of Clinical Laboratory of Medicine of Ningxia Medical University, XingQing District, Yinchuan, Ningxia, People's Republic of China.
Erqiang
E
Liu
Institute of Clinical Laboratory of Medicine of Ningxia Medical University, XingQing District, Yinchuan, Ningxia, People's Republic of China.
Tiantian
T
Yang
Institute of Clinical Laboratory of Medicine of Ningxia Medical University, XingQing District, Yinchuan, Ningxia, People's Republic of China.
Xiangjun
X
Chen
Institute of Clinical Laboratory of Medicine of Ningxia Medical University, XingQing District, Yinchuan, Ningxia, People's Republic of China.
Xiuqing
X
Wang
D000595:Amino Acid Sequence; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry*; D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism; D004396:Coloring Agents / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D054806:Magainins / Q000737:chemistry* / Q000494:pharmacology*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000166:cytology* / Q000187:drug effects*; D010539:Permeability / Q000187:drug effects; D011188:Potassium / Q000378:metabolism
D023181:Antimicrobial Cationic Peptides; D004396:Coloring Agents; D054806:Magainins; C031161:cecropin A; D011188:Potassium
cecropinA-magainin; flow cytometry; liposomes; methicillin-resistant Staphylococcus aureus; permeability; potassium ion; transmission electron microscopy