Related Experiment Video
Updated: Apr 14, 2026

Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing
Published on: July 7, 2020
Peptoid-based antimicrobial strategies against polymyxin-resistant Gram-negative bacteria
Shyam Kumar Mishra1,2, Jiawei Shen1, Tanzina Akter1,3
1School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW 2052, Australia.
Cationic peptoid TM8 shows potent activity against polymyxin-resistant bacteria, a growing global health threat. TM8 also synergizes with existing antibiotics and demonstrates low resistance development, offering a promising alternative for treating challenging infections.
Area of Science:
- Microbiology
- Infectious Diseases
- Drug Discovery
Background:
- Polymyxins are crucial for treating multidrug-resistant bacterial infections.
- Rising polymyxin resistance necessitates novel therapeutic strategies.
- Cationic peptoids are explored as potential antimicrobial agents.
Purpose of the Study:
- To evaluate the antibacterial activity of cationic peptoids against priority polymyxin-resistant bacteria.
- To identify potent peptoid candidates for combating emerging resistance.
Main Methods:
- Screening of nine cationic peptoids against polymyxin-sensitive and -resistant bacterial strains.
- Determination of minimum inhibitory concentrations (MICs) for peptoid TM8.
- Assessment of TM8 synergy with colistin, rifampicin, and ciprofloxacin.
- Evaluation of resistance development in Enterobacter cloacae to TM8 and ciprofloxacin.
- Flow cytometry analysis of membrane disruption.
- Investigation of cation effects on TM8 activity.
Main Results:
- Cationic peptoid TM8 exhibited potent activity against polymyxin-resistant bacteria (MIC 15.6 μg/mL).
- TM8 showed synergistic effects with colistin, rifampicin, and ciprofloxacin, reducing their MICs by 8- to 64-fold.
- Enterobacter cloacae did not develop resistance to TM8, unlike ciprofloxacin.
- TM8 demonstrated concentration-dependent membrane disruption.
- Divalent cations increased TM8 MIC up to 4-fold.
Conclusions:
- TM8 is a promising candidate antimicrobial agent against polymyxin-resistant bacteria.
- Further research into TM8's safety, pharmacokinetics, and pharmacodynamics is warranted.
More Related Videos
12:03Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
Published on: April 18, 2019
12:02An Efficient Method for the Synthesis of Peptoids with Mixed Lysine-type/Arginine-type Monomers and Evaluation of Their Anti-leishmanial Activity
Published on: November 2, 2016
Related Concept Videos
Inhibitors of Gram-positive Cell Wall Synthesis
Inhibitors of Bacterial Protein Synthesis
Antimicrobial Proteins
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
Mechanism of Antibiotic Resistance in MRSA
Combined Effects of Drugs: Synergism
Such synergistic combinations...
Development of Antibiotic Resistance