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Colostrum hexasaccharide, a novel Staphylococcus aureus quorum-sensing inhibitor
A Srivastava1, B N Singh2, D Deepak3
1Pharmacognosy & Ethnopharmacology Division, CSIR-National Botanical Research Institute, Lucknow, Uttar Pradesh, India Chemistry Department, Lucknow University, Lucknow, Uttar Pradesh, India.
Antimicrobial Agents and Chemotherapy
|February 4, 2015
Summary
Mare colostrum hexasaccharide (CHS) effectively inhibits Staphylococcus aureus virulence and biofilm formation. This study demonstrates CHS
Area of Science:
- Microbiology
- Biochemistry
- Pharmacology
Background:
- Quorum-sensing (QS) systems regulate bacterial virulence factors (VFs) and antibiotic resistance.
- Dietary molecules can modulate bacterial QS circuits, offering a strategy against pathogenicity.
- The role of colostrum hexasaccharide (CHS) in QS regulation remains unexplored.
Purpose of the Study:
- To investigate the potential of mare colostrum hexasaccharide (CHS) in inhibiting QS signaling in Staphylococcus aureus.
- To evaluate CHS's antibiofilm activity and its interference with QS systems.
- To assess CHS's impact on QS-regulated virulence factors and antibiotic resistance.
Main Methods:
- CHS isolation and characterization from mare colostrum using HPTLC, RP-HPLC-ELSD, NMR, and ESI-MS.
- Assessment of antibiofilm activity via microscopic analyses and microtiter-plate assays.
- Evaluation of QS interference by assessing degradation of acyl-homoserine lactones (AHLs) and inhibition of VFs.
Main Results:
- CHS significantly inhibited QS-regulated secretion of virulence factors (spreading, hemolysis, protease, lipase) in S. aureus at 5 mg/ml.
- CHS demonstrated strong inhibition of biofilm formation and effective eradication of established biofilms.
- CHS interfered with bacterial QS systems, evidenced by AHL degradation, and reduced S. aureus antibiotic resistance.
Conclusions:
- Mare colostrum hexasaccharide (CHS) is a potent inhibitor of Staphylococcus aureus virulence and biofilm formation.
- CHS interferes with bacterial quorum sensing and reduces antibiotic resistance.
- Mare colostrum represents a promising source for novel antibacterial compounds.
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