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Title: Correlation between fundamental binding forces and clinical prognosis of Staphylococcus aureus infections of medical implants

Abstract

Atomic force microscopy was used to “fish” for binding reactions between a fibronectin-coated probe (i.e., substrate simulating an implant device) and each of 15 different strains of S. aureus isolated from either patients with infected cardiac prosthesis (invasive group) or healthy human subjects (control group). There is a strong distinction (p=0.01) in the binding force-signature observed for the invasive vs. control populations. This observation suggests that a microorganism’s “force taxonomy” may provide a fundamental and practical indicator of the risk that bacterial infections pose to patients with implanted medical devices.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
901181
Report Number(s):
PNNL-SA-52975
Journal ID: ISSN 0743-7463; LANGD5; 19602; 9593; KP1704020; TRN: US200713%%84
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Langmuir, 23:2289-2292; Journal Volume: 23
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; PATIENTS; STAPHYLOCOCCUS; TAXONOMY; MECHANICAL HEART; BIOLOGICAL INDICATORS; AFM, binding, Staphylococcus aureus; Environmental Molecular Sciences Laboratory

Citation Formats

Yongsunthon, Ruchirej, Fowler, Vance, Lower, Brian H., Vellano, Francis P., Alexander, Emily, Reller, L. Barth, Corey, G. Ralph, and Lower, Steven. Correlation between fundamental binding forces and clinical prognosis of Staphylococcus aureus infections of medical implants. United States: N. p., 2007. Web. doi:10.1021/la063117v.
Yongsunthon, Ruchirej, Fowler, Vance, Lower, Brian H., Vellano, Francis P., Alexander, Emily, Reller, L. Barth, Corey, G. Ralph, & Lower, Steven. Correlation between fundamental binding forces and clinical prognosis of Staphylococcus aureus infections of medical implants. United States. doi:10.1021/la063117v.
Yongsunthon, Ruchirej, Fowler, Vance, Lower, Brian H., Vellano, Francis P., Alexander, Emily, Reller, L. Barth, Corey, G. Ralph, and Lower, Steven. Thu . "Correlation between fundamental binding forces and clinical prognosis of Staphylococcus aureus infections of medical implants". United States. doi:10.1021/la063117v.
@article{osti_901181,
title = {Correlation between fundamental binding forces and clinical prognosis of Staphylococcus aureus infections of medical implants},
author = {Yongsunthon, Ruchirej and Fowler, Vance and Lower, Brian H. and Vellano, Francis P. and Alexander, Emily and Reller, L. Barth and Corey, G. Ralph and Lower, Steven},
abstractNote = {Atomic force microscopy was used to “fish” for binding reactions between a fibronectin-coated probe (i.e., substrate simulating an implant device) and each of 15 different strains of S. aureus isolated from either patients with infected cardiac prosthesis (invasive group) or healthy human subjects (control group). There is a strong distinction (p=0.01) in the binding force-signature observed for the invasive vs. control populations. This observation suggests that a microorganism’s “force taxonomy” may provide a fundamental and practical indicator of the risk that bacterial infections pose to patients with implanted medical devices.},
doi = {10.1021/la063117v},
journal = {Langmuir, 23:2289-2292},
number = ,
volume = 23,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
  • Implanted medical devices (e.g., prosthetic heart valves, permanent pacemakers) significantly improve the quality of life for many humans. However, a common clinical observation is that such devices become colonized with potentially life-threatening Staphylococcus aureus biofilms, which are difficult to combat with host defenses or antibiotics. This study attempts to draw a correlation between the clinical outcome of patients with implanted cardiac devices and the fundamental binding forces ultimately responsible for the initiation of an S. aureus biofilm in-situ. Atomic force microscopy was used to measure forces between a fibronectin-coated probe (simulating a prosthetic implant) and 15 different strains of S.more » aureus isolated from either patients with infected cardiac devices (invasive population) or healthy human subjects (control population). The fibronectin-coated probe was repeatedly brought into and out of contact with a bacterium’s surface, “fishing” for a reaction with the cell’s fibronectin-binding proteins. More than 40,000 force profiles were measured on 5-10 different cells for each of the 15 clinical strains. A unique force-signature was observed for a binding event between the fibronectin-coated probe and the bacteria. When grouped by the frequency of this force-signature, there was a strong distinction (p=0.01) between the invasive and control populations of S. aureus. This discovery suggests that biofilm forming bacteria may be classified according to their “force taxonomy”, which could have a positive effect on health care as it bridges the long-standing disconnect between macroscopic, clinical investigations and nanometer-scale forces ultimately responsible for a bond between S. aureus and the surface of a prosthetic device.« less
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