Center for Biofilm Engineering News Update:  June, 2001 Volume 4, Issue 6 __________________________________________   Welcome New TAC Members   Microbia, Inc. Cambridge, MA Designated Representative: Bart Henderson, VP Business Development Microbia, Inc. has joined the CBE as our latest Industrial Associate. They are a privately held company based in Cambridge, Massachusetts developing antimicrobial drugs and microbial drug production technologies based on the physiological changes made by microbes as they sense and adapt to changes in their environment. The company's initial priorities are biofilm inhibition factors and anti-fungal drugs; and technology which enhances the production of fungally secreted drugs. The designated representative will be Bart Henderson, VP Business Development.   Reckitt Benckiser, Inc. Montvale, NJ Designated Representative: Karen McCue, Associate, Basic Research & Technology Reckitt Benckiser delivers solutions in household cleaning and health and personal care to consumers. The five product categories are fabric care, surface care, health & personal care, dish washing and home care. It sells its products in 180 countries and has operations in over 50 countries across all continents.   __________________________________________   Research Highlights   Paper Spotlight   The Role of Hydrodynamics on Biofilm Structure and Strength   This research investigates the role of hydrodynamics on the material properties and strength of aerobic and anaerobic biofilms. In previous studies we demonstrated that hydrodynamics could have a significant influence on biofilm structure. Under low shear conditions our biofilms formed irregular mound like micro-colonies whereas under higher shear the micro-colonies become elongated in the downstream direction, sometimes forming filamentous “streamers”. In this study we asked the question “does the magnitude of the fluid shear stress under which the biofilm was grown influence the material properties and strength of the biofilm?” Our hypothesis was that biofilms grown under higher shear would be stronger than those grown under lower shear. To investigate this we used an in situ microscopic method to relate changes in the fluid shear stress to induced deformation in biofilm structure. These tests were analogous to stress-strain and creep tests and provided both qualitative and quantitative information on the material properties of biofilm. We found that P. aeruginosa and Desulfovibrio biofilms grown at higher shear were more rigid (had a higher elastic modulus) than those grown under lower shear in parallel glass flow cells. We also found that biofilms grown under higher shear had a higher yield point (the transition stress at which the biofilms switched from behaving like elastic solids to behaving like viscoelastic fluids), and were therefore stronger, than those grown under lower shear. We hypothesized that the biofilm material properties were governed largely by the interactions between polymers in the extra-cellular polymeric slime (EPS) matrix and the relative proportion of labile hydrogen bonds to stronger ionic bonds which can cross-link carboxyl residues in the uronic acids commonly found in biofilm polymers. To test this hypothesis and to determine if the material properties of biofilms could be manipulated by changing the ionic environment we added the multivalent cation aluminum (Al+++) to the biofilm. This significantly increased the yield point and the elastic modulus of both types of biofilms, supporting the cross-linking hypothesis. We concluded that hydrodynamics not only influences the structure of the biofilm but also its strength. Whether this is due to selection, physical arrangement of the polymers, or genetic regulation remains to be found. This work is part of our ongoing research effort to investigate how the material properties of biofilm relate to both spontaneous and shear induced detachment. Both of which are important mechanisms in the dissemination of contamination in industrial systems.   This work was conducted primarily by Aaron Jacobsen, a participant in the Center 2000 Research Education for Undergraduates (REU) program and Braden Dunsmore, a visiting Ph.D. student from Dr. Lappin-Scotts group in Exeter UK.   Stoodley, P., Jacobsen, A., Dunsmore, B.C., Purevdorj, B., Wilson, S., Lappin-Scott, H.M. and Costerton, J.W. 2001. The influence of fluid shear and AlCl3 on the material properties of Pseudomonas aeruginosa PAO1 and Desulfovibrio sp. EX265 biofilms. Wat. Sci. Technol. 43:113-120.   __________________________________________   Don G. Willems Scholarship Award   Graduate students, Kristin Van Andel and Elsa Meiser, were both winners of the Don G. Willems Scholarship. The Donald G. Willems Scholarship was presented to the two MSU students during a recent state meeting of the American Water Works Association and the Water Environment Association. Elsa and Kristin were awarded $500 in memory of Don Willems, a quiet, supportive Montana wastewater professional. As the scholarship certificate indicates "... Don recognized worth and ability in other people, and did not so much rule over people as to work with them. He gave people chances to prove themselves and was responsible for giving many young people in Montana the career opportunities they desired." Ms. Meiser recently began her graduate studies with Drs. Joel Cahoon and Al Cunningham while Ms. Van Andel is finishing her M.S. degree with Dr. Anne Camper.   __________________________________________   Education   Research Experience for Undergraduates - Summer 2001   This summer's Research Experience for Undergraduate (REU) students arrived at the CBE on June 4th for a ten-week program. A full schedule is planned for the students and by far the most important interaction of the summer is the time spent working with the CBE students, staff and faculty. The following is a listing of the projects and students.   Distribution of freshwater microorganisms in paper machine biofilms REU Student: Patricia L. Ball Mentors: Anne Camper, CBE and Laura Rice, Senior Microbiologist, Nalco Chemical Company   Design and validate a method for enumerating biofilm cells on an antimicrobial surface using conventional plating techniques and to determine a protocol to neutralize surface-bound Polyhexamethylene Biguanide (PHMB) REU Student: Summer Gibbs Mentors: Joanna Heersink, CBE and Robert Orr, Research Associate, Kendall Healthcare   Biodegradation of MTBE REU Student: Sarah Hall Mentors: Joel Cahoon and Elsa Meiser, CBE   The relationship between biofilm and acquired antimicrobial resistance REU Student: Riva Martin Mentors: Phil Stewart, CBE and Tom Palys, Senior Research Microbiologist/Biotech Research, Arch Chemicals, Inc.   Bioelectric effect: Determination of the efficacy of induced field for the remediation of biofilms REU Student: Anders Spike Mentor: Mark Pasmore, CBE   Comparing the efficacy of bromine and chlorine against suspended cells verses biofilm REU Student: Matthew Strauss Mentors: Darla Goeres, CBE and Joe Sauer, Senior Research & Development Advisor, Albemarle, Corp.   Influence of growth environment on protein expression in Pseudomonas aeruginosa biofilms REU Student: Kimberly White Mentors: Paul Stoodley/Karin Sauer, CBE   For more details see http://www.erc.montana.edu/CBEssentials-SW/education/REU/students_REU2001.htm   ________________________________________   Upcoming CBE Meetings and Workshops   Summer 2001 TAC Meeting - July 24-26 The CBE Technical Advisory Committee (TAC) Meeting has been scheduled for July 24-26, 2001 at the Montana State University-Bozeman campus, in Bozeman, Montana. If you are interested in attending, please contact Paul Sturman, phone: (406) 994-2102 or email: paul_stu@erc.montana.edu.   Note: If you plan to attend the pre-meeting reception at the Gran Tree Inn, Monday July 23rd at 6pm, please register with Susan Cooper at 406 994-4770 or email susan_c@erc.montana.edu. There is no charge for the reception.   Workshops will take place on Monday, July 23rd and research presentations will follow on Tuesday through Thursday, July 24th - 26th. See the TAC Workshop Survey below.   _______   TAC Workshop Survey   The CBE is again planning to host a biofilm methods workshop at our Summer TAC meeting. The workshop is scheduled for July 23, 2001. In an effort to tailor this workshop to the needs of our members, we are soliciting input from Industrial Associates regarding topics which are of particular interest. If you are planning to attend the TAC meeting, and you would like to request a particular topic be presented at the pre-meeting workshop, please email Paul Sturman with your request (paul_stu@erc.montana.edu).   _______   Microsensor Workshop   An upcoming summer workshop on the manufacture and application of microsensors will be held August 20-24, 2001, at the CBE. The registration deadline for this workshop is June 15th. See the conference details and registration form at: http://www.erc.montana.edu/CBEssentials-SW/MicrosensorWorkshop/default.htm   For other upcoming conferences see the Events Calendar at http://www.erc.montana.edu/CBEssentials-SW/whats_new/index.htm   _________________________________________   CBE People in Action   Darla Goeres presented an industrial seminar at Biolab, Inc , Decator, GA, which focused on the control of biofilms in pools and spas, May 2, 2001.   Dr. William Costerton, as invited speaker presented "How We Will Use the On Line Optical Biofilm Probe" to research personnel at Intellectual Optical Systems (IOS), Los Angeles, CA, May 7, 2001.   Dr. William Costerton, invited to the “Rats in Space” program at Ames Research Center in San Jose, CA, May 8, 2001. He provided expert opinion regarding design feasibility with respect to bacterial contamination of the water, feeder, and waste management sub-systems.   Dr. William Costerton was an invited speaker at the University of California-Los Angeles Pharmacology Department, May 9, 2001. He presented "Biofilms in Oral Biology."   Dr. Paul Stoodley, as invited speaker presented "Detachment and Other Dynamic Processes in Bacterial Biofilms," to the Planetary Protection Technologies Group, Jet Propulsion Laboratory, Pasadena, CA, May 10, 2001.   Dr. William Costerton as invited speaker, presented "How to Assess the Efficacy of Antibacterial Materials" to Genzyme, Cambridge, MA, May 16, 2001.   Dr. William Costerton, as an American Society for Microbiology (ASM) foundation speaker, presented "Biofilms in Health and Disease," Waterclub at Siro's in North Quincy, MA, May 16, 2001.   Dr. William Costerton was invited to speak to the research personnel at Microbia, Boston, MA, May 17, 2001.   Dr. William Costerton presented "How Do We Teach the Fast-Breaking News: Biofilms and Chronic Infections?", at the American Society for Microbiology (ASM) 8th Undergraduate Microbiology Education Conference, Orlando, FL, May 18, 2001.   Dr. Andrew Neal, presented "Alternative Electron Acceptors for Respiration by Sulfate-Reducing Bacteria Growing on Hematite Mineral Surfaces" at the ASM General Meeting, Orlando, FL, May 20-24, 2001.   Dr. Mark Pasmore, presented "The Effects of Signaling Analogs on Biofilm Behavior" at the ASM General Meeting, Orlando, FL, May 20-24, 2001.   Jill Petik, presented a poster entitled "Presence and Qualitative Analysis of Staphylococcus aureus in the Vagina During Menstruation" at the ASM General Meeting, May 20-24, 2001.   Dr. Karin Sauer, presented "Biofilm Phenotype and Signaling Mechanisms in Pseudomonas species" and a poster entitled "Characterization of Phenotypic Changes in Pseudomonas putida in Response to Surface-Associated Growth'" at the ASM General Meeting, May 20-24, 2001.   Dr. Mark Shirtliff, presented "Comparison of in vivo versus in vitro Methicillin Resistant Staphylococcus aureus (MRSA) Gene Expression Using Differential Gene Expression by Replica Plate Hybridization (dGERPH), " at the ASM General Meeting, May 20-24, 2001.   Dr. William Costerton presented "The Role of Biofilms in Chronic Infection," in a session titled "Biofilms in Chronic Bacterial Infections" at the 101st General Meeting for the American Society for Microbiology, Orlando, FL, May 25, 2001.   __________________________________________   Theses   See theses abstracts at http://www.erc.montana.edu/Res-Lib99-SW/pubs/Theses/default.htm     __________________________________________   Web Watch   The BiofilmsOnline.com site has been upgraded to a searchable database. The website format remains the same with a new feature of drop down boxes to display archived information.  See the June issue at http://www.BiofilmsOnline.com.   Check our Recent Web Updates page created to make it easy for you to locate new information on the CBE web. See http://www.erc.montana.edu/Recent%20Web%20Updates/default.htm     __________________________________________   Newsletter Listserve   The CBE News Update is a listserve newsletter. If you need to subscribe or unsubscribe from the listserve, follow the directions at the following CBE website.   http://www.erc.montana.edu/Res-Lib99-SW/newsarchives/subscribe.htm   An alternative to subscribing to the listserve is to view the CBE News Update on our web page at http://www.erc.montana.edu/Ind-Col99-SW/Current_Newsletter/default.htm. Newsletter archives can be found at http://www.erc.montana.edu/Res-Lib99-SW/newsarchives/index.htm   __________________________________________   Diane Williams  editor of the CBE News Update