MSU biofilms research helps set standards for everyday products

August 25, 2008

BOZEMAN -- Montana State University scientist Darla Goeres knows that there is more than one way to grow a biofilm, a fact that she uses to make sure that when a product claims it kills "99 percent" of bacteria, it really does the job.

Biofilms are the extremely common communities of bacteria that form on most wet surfaces. They range from the plaque on teeth to the slime on streamside rocks to the sludge that clogs pipes.

Most biofilms are harmless, but some have been linked to ailments such as urinary tract infections, gingivitis and infections around implanted devices like artificial joints and heart valves.

"In the world that I study, everybody's trying to kill the biofilm," said Goeres, a research professor in the Department of Chemical and Biological Engineering. "But there's not a concrete answer for that, and that's why you need to understand methods."

Earlier this year, Goeres was awarded a five-year, $1.7 million contract from the Environmental Protection Agency to work on new ways to measure how well antimicrobial products perform against biofilms.

"The EPA contract provides a solid basis of support," Goeres said. "That's why we can be one of the few labs in the world that can focus on methods development."

Goeres works in the Standardized Biofilms Methods Laboratory at MSU's Center for Biofilm Engineering. There, she develops standards for growing, treating and sampling biofilms.

All biofilms are unique. They are composed of varying numbers of different bacteria, and the conditions under which these bacteria form a biofilm can make a big difference in the resulting slime. So a product designed to kill one biofilm might not work on any others, which makes proving the effectiveness of antibacterial cleaning products tricky.

"Every time a person buys a product with an EPA-approved efficacy claim, such as 'kills 99 percent of bacteria,' the public trusts the validity of the process used to prove that claim," Goeres said.

However, the method a company uses to prove its product's effectiveness can make a big difference in the test results. Until recently, most methods for testing products involved growing bacteria in a way that's not consistent with the real world, Goeres said.

"Our goal is to grow bacteria in a way that's relevant to how the bacteria exist where the product is used," she said. "That way, we can have more confidence in the product's actual effectiveness, and so can the public."

The EPA contract will allow Goeres to hire two additional undergraduate students for her lab, where they will receive training and experience that will help them continue into graduate school or biofilms jobs. The lab normally hires four to six undergraduates each year.

Goeres said her biofilm methods work, which can seem detached from the real world, is ultimately about making sure people can trust the products they're using to keep their homes clean.

"So many results depend on the process a person uses," Goeres said. "To have only one way to grow a biofilm isn't going to cut it."

Montana State University

The Biofilm Primer (Springer Series on Biofilms)
by J. William Costerton (Author)

This book details the widely accepted hypothesis that the majority of bacteria in virtually all ecosystems grow in matrix-enclosed biofilms. The author, who first proposed this biofilm hypothesis, uses direct evidence from microscopy and from molecular techniques, arguing cogently for moving beyond conventional culture methods that dominated microbiology in the last century. Bacteria grow predominantly in biofilms in natural, engineered, and pathogenic ecosystems; this book provides a solid basis for the understanding of bacterial processes in environmental, industrial, agricultural, dental and medical microbiology. Using a unique "ecological" perspective, the author explores the commensal and pathogenic colonization of human organ systems.

Microbial Biofilms: Current Research and Applications
by Gavin Lear (Editor), Gillian D. Lewis (Editor)

Biofilms are the default mode-of-life for many bacterial species. The three-dimensional structure of the biofilm provides the associated microbial communities with additional protection from predation, toxic substances, and physical perturbation. The variety of microniches provided by the biofilm also promotes a huge diversity of microbial life and metabolic potential. These complex and highly structured communities help to maintain the health of soils and waters. Current applications of biofilms include the degradation of toxic substances in soil and water, the commercial production of chemicals, and the generation of electricity. However, biofilm-based infections cause harm to millions of humans annually. In addition, biofilms can affect the quality and yield of crops and cause...

Fundamentals of Biofilm Research
by Zbigniew Lewandowski (Author), Haluk Beyenal (Author)

The history of natural sciences demonstrates that major advances in the understanding of natural processes follow the development of relevant tools. The progress of biofilm research is no different. While individual areas have mushroomed in recent years, difficulties in reproducing results, communicating new findings, and reconciling differences in conceptual versus mathematical advances are holding back the true growth of the field. Fundamentals of Biofilm Research offers a system of compatible tools and measurements that can be used to conduct biofilm studies and consistently interpret their results. After extensive testing and refinement in labs and classrooms over twenty years, the authors introduce a coherent system of conceptual, physical, computational, and virtual tools to...

Microbial Biofilms
by Mahmoud Ghannoum (Author)

Medical Implications of Biofilms
by Michael Wilson (Editor), Deirdre Devine (Editor)

Interest in biofilms has increased dramatically in recent years. New microscopic and molecular techniques have revolutionized our understanding of biofilm structure, composition, organization, and activities. This book brings advances in the prevention and treatment of biofilm-related diseases to the attention of clinicians and medical researchers. Human tissues often support complex microbial communities growing as biofilms that can cause infections. As microbes in biofilms exhibit increased tolerance toward anti-microbial agents and decreased susceptibility to host defense systems, biofilm-associated diseases have become increasingly difficult to treat.

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.

Biofilm Reactors WEF MOP 35 (Water Resources and Environmental Engineering Series)
by Water Environment Federation (Author)

The latest Methods for Wastewater Treatment Using Fixed-Film Processes This Water Environment Federation resource provides complete coverage of pure fixed-film and hybrid treatment systems, along with details on their design, performance, and operational issues. Biofilm Reactors discusses factors that affect the design of the various processes, appropriate design criteria and procedures, modeling techniques, equipment requirements, and construction methods. Operational issues associated with each type of process are presented, including potential problems and corrective actions. Real-world case studies illustrate the application of the technologies presented in this authoritative volume. Biofilm Reactors covers: Biology of fixed-film processes Trickling filter and...

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...

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...

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.