No hiding place for infecting bacteria

March 16, 2009

Preventing Pseudomonas aeruginosa biofilms

Scientists in Colorado have discovered a new approach to prevent bacterial infections from taking hold. Writing in the Journal of Medical Microbiology, Dr Quinn Parks and colleagues describe how they used enzymes against products of the body's own defence cells to prevent Pseudomonas aeruginosa bacteria from building a protective biofilm which enables them to avoid both the body's immune mechanisms and antibiotics.

When the body's defence cells, called neutrophils, attack P. aeruginosa, the cell contents - including a protein called F-actin and the cell's DNA - are released. P. aeruginosa uses these cell proteins as a scaffold to build a protective biofilm making these infections very difficult to treat. P. aeruginosa biofilms cause disease in burns, wounds, contact lens infections and are particularly prevalent in the lungs of cystic fibrosis patients.

"We specifically targeted the F-actin protein with a negatively charged peptide, and the DNA with the enzyme DNase, which both prevented and disrupted the formation of P. aeruginosa biofilms in the presence of human neutrophils." said Dr Parks. "These results suggest a new combined therapeutic strategy for the treatment of P. aeruginosa infections.

Society for General Microbiology

Microbially-mediated glass dissolution and sorption of metals by Pseudomonas aeruginosa cells and biofilm [An article from: Journal of Hazardous Materials]
by G. Aouad (Author), J.L. Crovisier (Author), V.A. Geoffroy (Author), J. Meyer (Author)

This digital document is a journal article from Journal of Hazardous Materials, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
A basaltic glass and a vitrified bottom ash were incubated at 25^oC in a growth medium (based on casaminoacids) inoculated with Pseudomonas aeruginosa. Bacterial growth and mineral concentrations in different compartments (bacterial cells, growth medium and biofilm) were monitored in short-term (3 days), and long-term experiments involving repeated renewals of the culture medium during 174 days. In short-term experiments, while the concentration of iron increased in the presence of bacteria, a decrease...

The Role of Biofilms in Device-Related Infections (Springer Series on Biofilms)
by Mark Shirtliff (Editor), Jeff G. Leid (Editor)

Approximately 60% of all hospital-associated infections, over one million cases per year, are due to biofilms that have formed on indwelling medical devices. Device-related biofilm infections increase hospital stays and add over one billion dollars/year to U.S. hospitalization costs. Since the use and the types of indwelling medical devices commonly used in modern healthcare are continuously expanding, especially with an aging population, the incidence of biofilm infections will also continue to rise. The central problem with microbial biofilm infections of foreign bodies is their propensity to resist clearance by the host immune system and all antimicrobial agents tested to date. In fact, compared to their free floating, planktonic counterparts, microbes within a biofilm are 50 – 500...

Biofilm Highlights (Springer Series on Biofilms)
by Hans-Curt Flemming (Editor), Jost Wingender (Editor), Ulrich Szewzyk (Editor)

Living in biofilms is the common way of life of microorganisms, transiently immobilized in their matrix of extracellular polymeric substances (EPS), interacting in many ways and using the matrix as an external digestion and protection system. This is how they have organized their life in the environment, in the medical context and in technical systems – and has helped make them the oldest, most successful and ubiquitous form of life. In this book, hot spots in current biofilm research are presented in critical and sometimes provocative chapters. This serves a twofold purpose: to provide an overview and to inspire further discussions. Above all, the book seeks to stimulate lateral thinking.

Control of Biofilm Infections by Signal Manipulation (Springer Series on Biofilms)
by Naomi Balaban (Editor), J.W. Costerton (Editor)

The number of patients affected by and dying from what can be considered as a "biofilm disease" is higher than heart disease and cancer combined. Thus, this is a hugely important work that describes the molecular mechanisms of cell-to-cell communication among bacterial cells in a biofilm, the development of antibiofilm inhibitors such as quorum-sensing inhibitors, and the use of biofilm inhibitors to prevent and treat bacterial infections in humans and other animals.

Bacterial Biofilms (Current Topics in Microbiology and Immunology)
by Tony Romeo (Editor)

Throughout the biological world, bacteria thrive predominantly in surface attached, matrix enclosed, multicellular communities or biofilms, as opposed to isolated planktonic cells. This choice of lifestyle is not trivial, as it involves major shifts in the use of genetic information and cellular energy, and has profound consequences for bacterial physiology and survival. Growth within a biofilm can thwart immune function and antibiotic therapy and thereby complicate the treatment of infectious diseases, especially chronic and foreign device-associated infections. Modern studies of many important biofilms have advanced well beyond the descriptive stage, and have begun to provide molecular details of the structural, biochemical and genetic processes that drive biofilm formation and its...

Biofilms and Veterinary Medicine (Springer Series on Biofilms)
by Steven L. Percival (Editor), Derek C. Knottenbelt (Editor), Christine A. Cochrane (Editor)

Biofilms are implicated in many common medical problems including urinary tract infections, catheter infections, middle-ear infections, dental plaque, gingivitis, and some less common but more lethal processes such as endocarditis and infections in cystic fibrosis. However, the true importance of biofilms in the overall process of disease pathogenesis has only recently been recognized. Bacterial biofilms are one of the fundamental reasons for incipient wound healing failure in that they may impair natural cutaneous wound healing and reduce topical antimicrobial efficiency in infected skin wounds. Their existence explains many of the enigmas of microbial infection and a better grasp of the process may well serve to establish a different approach to infection control and management. ...

Biofilm Infections
by Thomas Bjarnsholt (Editor), Peter Østrup Jensen (Editor), Claus Moser (Editor), Niels Høiby (Editor)

This book will cover both the evidence for biofilms in many chronic bacterial infections as well as the problems facing these infections such as diagnostics and treatment regimes. A still increasing interest and emphasis on the sessile bacterial lifestyle biofilms has been seen since it was realized that that less than 0.1% of the total microbial biomass lives in the planktonic mode of growth. The term was coined in 1978 by Costerton et al. who defined the term biofilm for the first time.In 1993 the American Society for Microbiology (ASM) recognised that the biofilmmode of growth was relevant to microbiology. Lately many articles have been published on the clinical implications of bacterial biofilms. Both original articles and reviews concerning the biofilm problem are available.

Microbial Biofilms (Biotechnology Research)
by Hilary M. Lappin-Scott (Editor), J. William Costerton (Editor)

The formation of microcolonies on surfaces is an important bacterial survival strategy. These biofilms occur on both inert and living systems, making them important to a wide range of scientific disciplines. This book first provides an analysis of the chemical, ecological and physical processes involved with the development of biofilms and their interactions with surfaces. The next section deals with biofilms on non-living surfaces. Biofilms have important engineering implications, such as in mining industries, the corrosion of pipelines and pure and waste water industries. Biofilms have medical significance when associated with the mouth, urinary tract and urinogenital tract. In addition, they form in plant root systems and in animals, such as the ruminant digestive tract, and so are...

Biofilm Eradication and Prevention: A Pharmaceutical Approach to Medical Device Infections
by Tamilvanan Shunmugaperumal (Author)

Biofilm Eradication and Preventions presents the basics of biofilm formation on medical devices, diseases related to this formation, and approaches pharmaceutical researchers need to take to limit this problem. Split into three parts, the first deals with the development and characterization of biofilm on the surfaces of implanted or inserted medical devices. Questions as to why biofilms form over medical device surfaces and what triggers biofilm formation are addressed. In the second section, the author discusses biofilm-mediated chronic infections occurred in various organs (eyes, mouth, wounds) and pharmaceutical and drug delivery knowledge gained from research in these area. The third part explores pharmaceutical approaches like lipid-and polymer-based drug delivery carriers for...

Biofilms in the Food Environment (Institute of Food Technologists Series)
by Hans P. Blaschek (Editor), Hua H. Wang (Editor), Meredith E. Agle (Editor)

Biofilms in the Food Environment examines biofilms produced by food-borne microorganisms, the risks associated with biofilms in the food chain, the beneficial applications of biofilms in the food environment, and approaches for biofilm removal to improve sanitation and safety in the food environment.

Specifically, this book provides:

an introduction into the emerging and exciting field of biofilm research in the food environment
a summary of advanced knowledge in medical microbiology and engineering and its applicability to food biofilm research, and
potential directions for biofilm intervention and industrial beneficial applications that may have direct impact on food safety and public health.

Biofilms in the Food Environment is intended to serve as a...