Related Experiment Video

Updated: Apr 4, 2026

From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028
09:08

From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028

Published on: January 13, 2017

17.9K

Optimization of oncocin for antibacterial activity using a SPOT synthesis approach: extending the pathogen spectrum

Daniel Knappe1,2, Serge Ruden3, Stefanie Langanke4,5

  • 1Institute of Bioanalytical Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, Deutscher Platz 5, 04103, Leipzig, Germany. daniel.knappe@bbz.uni-leipzig.de.

Amino Acids
|September 4, 2015
PubMed

Insights

Developing novel antimicrobial drugs is crucial for combating multidrug-resistant bacteria. Researchers enhanced proline-rich antimicrobial peptides, creating analogs with significantly improved activity against Pseudomonas aeruginosa and Staphylococcus aureus.

Area of Science:

  • Microbiology
  • Medicinal Chemistry
  • Peptide Science

Background:

  • Multidrug-resistant bacteria pose a significant global health threat, necessitating novel antimicrobial agents.
  • Proline-rich antimicrobial peptides show promise but exhibit limited efficacy against key pathogens like Pseudomonas aeruginosa and Staphylococcus aureus.
  • Suboptimal uptake or target interaction may explain the reduced effectiveness of existing peptides.

Purpose of the Study:

  • To synthesize and evaluate a library of oncocin analogs to identify improved antimicrobial agents.
  • To investigate the impact of single amino acid substitutions on peptide activity against Gram-negative and Gram-positive bacteria.
  • To develop potent peptide-based therapeutics against challenging multidrug-resistant pathogens.

Main Methods:

  • Peptide arrays on cellulose membranes were synthesized using cleavable linkers for efficient peptide release.
  • A library of 361 singly substituted oncocin analogs was generated by systematic amino acid replacement.
  • Peptide efficacy was assessed against a luminescent Pseudomonas aeruginosa strain and confirmed against other bacterial species.

Main Results:

  • Thirteen oncocin substitutions demonstrated promising enhanced antibacterial activity.
  • Larger-scale synthesis confirmed the improved efficacy of these selected analogs.
  • A combined double-substitution analog exhibited a 10-fold increase in activity against P. aeruginosa and a 100-fold increase against S. aureus.

Conclusions:

  • Systematic peptide modification can significantly enhance antimicrobial potency.
  • Optimized oncocin analogs represent promising lead compounds for developing new treatments against multidrug-resistant bacteria.
  • The developed analogs show high activity, with minimal inhibitory concentrations as low as 0.5 µg/mL for S. aureus.
Keywords:
OncocinProline-rich antimicrobial peptidePseudomonas aeruginosaQuartz crystal microbalanceSPOT synthesis

More Related Videos

Synthesis of Masarimycin, a Small Molecule Inhibitor of Gram-Positive Bacterial Growth09:10

Synthesis of Masarimycin, a Small Molecule Inhibitor of Gram-Positive Bacterial Growth

Published on: January 7, 2022

2.8K
A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products07:59

A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products

Published on: October 4, 2019

10.5K

Related Concept Videos

Production of Antibiotics01:27

Production of Antibiotics

Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
82
Antibiotic Selection00:57

Antibiotic Selection

Overview
62.2K
Production of Pharmaceuticals01:30

Production of Pharmaceuticals

Industrial insulin production uses genetically engineered E. coli expressing a proinsulin gene controlled by a tryptophan promoter and containing a methionine linker for later cleavage. The cells also carry ampicillin resistance for selective growth. Seed cultures are stored at −80 °C and production begins by thawing a small amount to inoculate starter cultures, which are progressively scaled to a 50,000-L bioreactor. In the bioreactor, E. coli grow in nutrient-rich media under...
64
Antimicrobial Effectiveness01:28

Antimicrobial Effectiveness

The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...
2.0K
Inhibitors of Bacterial Protein Synthesis01:25

Inhibitors of Bacterial Protein Synthesis

Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...
54
Inhibitors of Bacterial DNA Synthesis01:28

Inhibitors of Bacterial DNA Synthesis

Bacterial pathogens depend on precise and efficient DNA replication to sustain infection. Two type II topoisomerases—DNA gyrase and topoisomerase IV—are critical to this process, as they resolve DNA supercoiling and unlink chromosomes during replication. Fluoroquinolones, synthetic derivatives of quinolones, exploit this mechanism by stabilizing the transient DNA–enzyme cleavage complex, preventing strand religation, and causing lethal double-strand breaks. These...
54