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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

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Bacteriophage-derived CHAP domain protein, P128, kills Staphylococcus cells by cleaving interpeptide cross-bridge of

Sudarson Sundarrajan1, Junjappa Raghupatil1, Aradhana Vipra1

  • 1GangaGen Biotechnologies Pvt. Ltd, No. 12 5th cross, Raghavendra layout, Tumkur road, Yeshwantpur, Bangalore 560022, India.

Microbiology (Reading, England)
|July 16, 2014
PubMed

Insights

P128 protein resistance in Staphylococcus mutants involves femA gene mutations, impacting peptidoglycan cross-bridge cleavage. These resistant mutants exhibit reduced fitness and altered antibiotic sensitivity.

Area of Science:

  • Microbiology
  • Biochemistry
  • Molecular Biology

Background:

  • P128 is a novel anti-staphylococcal protein engineered from phage-K and lysostaphin components.
  • Understanding resistance mechanisms is crucial for developing effective anti-staphylococcal therapies.

Purpose of the Study:

  • To investigate the mechanism of action and resistance emergence against P128 in Staphylococcus species.
  • To characterize P128-resistant mutants and identify genetic alterations responsible for resistance.

Main Methods:

  • Isolation and characterization of P128-resistant Staphylococcus mutants.
  • Analysis of mutant fitness, virulence, and antibiotic sensitivity.
  • Sequencing of the femA gene and investigation of peptidoglycan cross-bridge cleavage.

Main Results:

  • P128-resistant mutants exhibited reduced growth and virulence, with some MRSA mutants regaining sensitivity to beta-lactams.
  • Mutations in the femA gene were identified in resistant strains, suggesting impaired peptidoglycan cross-bridge formation.
  • P128 effectively cleaved pentaglycine cross-bridges and demonstrated activity against lysostaphin-resistant strains, including Staphylococcus haemolyticus.

Conclusions:

  • Resistance to P128 in Staphylococcus spp. is associated with femA mutations and compromised peptidoglycan cross-bridge integrity.
  • P128 exhibits a unique mechanism of action, targeting pentaglycine cross-bridges and showing efficacy against certain lysostaphin-resistant staphylococci.

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