Impedimetric Detection of Pathogenic Gram-Positive Bacteria Using an Antimicrobial Peptide from Class IIa Bacteriocins

2014 ◽  
Vol 86 (3) ◽  
pp. 1693-1700 ◽  
Author(s):  
Hashem Etayash ◽  
Keren Jiang ◽  
Thomas Thundat ◽  
Kamaljit Kaur
Keyword(s):  
Antimicrobial Peptide ◽  
Gram Positive ◽  
Gram Positive Bacteria

scholarly journals Effects of Antibacterial Peptide F1 on Bacterial Liposome Membrane Integrity

2021 ◽  
Vol 8 ◽  
Author(s):  
Qun Wang ◽  
Bo Peng ◽  
Mingyue Song ◽  
Abdullah ◽  
Jun Li ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Membrane Structure ◽  
Bacterial Membrane ◽  
Phospholipid Membranes ◽  
Phospholipid Membrane ◽  
Gram Positive ◽  
Liposome Membrane ◽  
Gram Negative ◽  
Bacterial Membranes ◽  
Gram Positive Bacteria

Previous studies from our lab have shown that the antimicrobial peptide F1 obtained from the milk fermentation by Lactobacillus paracasei FX-6 derived from Tibetan kefir was different from common antimicrobial peptides; specifically, F1 simultaneously inhibited the growth of Gram-negative and Gram-positive bacteria. Here, we present follow-on work demonstrating that after the antimicrobial peptide F1 acts on either Escherichia coli ATCC 25922 (E. coli) or Staphylococcus aureus ATCC 63589 (S. aureus), their respective bacterial membranes were severely deformed. This deformation allowed leakage of potassium and magnesium ions from the bacterial membrane. The interaction between the antimicrobial peptide F1 and the bacterial membrane was further explored by artificially simulating the bacterial phospholipid membranes and then extracting them. The study results indicated that after the antimicrobial peptide F1 interacted with the bacterial membranes caused significant calcein leakage that had been simulated by different liposomes. Furthermore, transmission electron microscopy observations revealed that the phospholipid membrane structure was destroyed and the liposomes presented aggregation and precipitation. Quartz Crystal Microbalance with Dissipation (QCM-D) results showed that the antimicrobial peptide F1 significantly reduced the quality of liposome membrane and increased their viscoelasticity. Based on the study's findings, the phospholipid membrane particle size was significantly increased, indicating that the antimicrobial peptide F1 had a direct effect on the phospholipid membrane. Conclusively, the antimicrobial peptide F1 destroyed the membrane structure of both Gram-negative and Gram-positive bacteria by destroying the shared components of their respective phospholipid membranes which resulted in leakage of cell contents and subsequently cell death.

Antimicrobial-peptide coating that ruptures the wall of Gram positive bacteria

2014 ◽  
Vol 30 ◽  
pp. e86-e87
Author(s):  
X. Chen ◽  
H. Hirt ◽  
Y. Li ◽  
S.-U. Gorr ◽  
C. Aparicio
Keyword(s):  
Antimicrobial Peptide ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Peptide Coating

Surface-Conjugated Antimicrobial Peptide Leucocin A Displays High Binding to Pathogenic Gram-Positive Bacteria

2014 ◽  
Vol 6 (2) ◽  
pp. 1131-1138 ◽  
Author(s):  
Hashem Etayash ◽  
Lana Norman ◽  
Thomas Thundat ◽  
Michael Stiles ◽  
Kamaljit Kaur
Keyword(s):  
Antimicrobial Peptide ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
High Binding ◽  
Leucocin A

scholarly journals Antimicrobial Peptide Resistance Mechanisms of Gram-Positive Bacteria

Antibiotics ◽  
2014 ◽  
Vol 3 (4) ◽  
pp. 461-492 ◽  
Author(s):  
Kathryn Nawrocki ◽  
Emily Crispell ◽  
Shonna McBride
Keyword(s):  
Antimicrobial Peptide ◽  
Resistance Mechanisms ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Antimicrobial Peptide Resistance

scholarly journals Development of a Potent Antimicrobial Peptide With Photodynamic Activity

2021 ◽  
Vol 12 ◽  
Author(s):  
Di Zhang ◽  
Jingyi Chen ◽  
Qian Jing ◽  
Zheng Chen ◽  
Azeem Ullah ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Red Light ◽  
Antimicrobial Effect ◽  
Resistant Bacteria ◽  
Infection Model ◽  
Light Illumination ◽  
Gram Positive ◽  
Antibiotic Resistant ◽  
Gram Positive Bacteria ◽  
Mouse Infection Model

The emergence of antibiotic-resistant bacteria poses a serious challenge to medical practice worldwide. A small peptide with sequence RWRWRW was previously identified as a core antimicrobial peptide with limited antimicrobial spectrum to bacteria, especially Gram-positive bacteria. By conjugating this peptide and its analogs with lipophilic phthalocyanine (Pc), we identified a new antibiotic peptide [PcG3K5(RW)3]. The peptide demonstrates increased antimicrobial effect to both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. In addition, Pc also provides added and potent antimicrobial effect upon red light illumination. The inhibitory efficacy of PcG3K5(RW)3 was increased by ~140-fold to nanomolar range upon illumination. Moreover, PcG3K5(RW)3 was safe for mammalian cell and promoted wound healing in the mouse infection model. Our work provides a new direction to optimize antimicrobial peptides to enhance antimicrobial efficacy.

Sign in / Sign up

Export Citation Format

Share Document