Center for Biofilm Engineering News Update:  November, 2002 Volume 5, Issue 11   __________________________________________   Research Highlights   Paper Spotlight    Microbial Growth Kinetics on Multiple Substrates, by Nurdan Yurt   The goal of this study was to represent the planktonic growth rate of Leptothrix discophora SP-6 by a suitable mathematical model and to calculate biokinetic parameters associated with this model. L. discohora SP-6 is a model manganese oxidizing bacterium that we use to study microbially influenced corrosion of stainless steels in laboratory conditions. To simplify calculating the growth parameters from the chemostat data, researchers often use single substrate growth models (mostly Monod type) (noninteractive model). However, it is well known that the microbial growth rate often depends on more than one substrate (interactive or multiplicative model). To take into account more than one substrate, we operated a chemostat and quantified the steady-state growth parameters based on mass balances for pyruvate, dissolved oxygen, microorganisms and their respective concentrations.  We then used MATLAB programming to estimate biokinetic parameters by testing whether single or double substrate growth models would predict the specific growth rate more accurately.  The single growth models tested were Monod (1949), Tessier (1942), Moser (1958) and Contois (1959).   The results showed that the microbial growth was limited by both pyruvate and dissolved oxygen. A combined growth kinetics model using Monod growth kinetics for pyruvate and Tessier growth kinetics for oxygen showed the best correlation with the experimental data.  We believe the ready-to-use algorithm and computer program will be used by other researchers to calculate biokinetic parameters of different microorganisms.   Reference:  Yurt, N., J. Sears, and Z. Lewandowski, "Multiple Substrate Growth Kinetics of Leptothrix discophora SP-6," Biotechnol. Prog., 18:994-1002 (2002).      _______   Scientific American Special Issue on Oral Health   Scientific American Magazine and Philips have produced a first-ever special issue focusing on “Emerging Trends in Oral Care:  The Biofilm Revolution.”  The table of contents include: - Moving Toward a New Kind of Dentistry, by Joel Berg - Battling Biofilms, by J.W. Costerton and Philip S. Stewart - Biofilms, Smile!  You’re on Confocal Scanning Laser Microscopy Camera, by Paul Stoodley - Bad Breath?  Blame Biofilms, by Mel Rosenberg - Connecting “R” to “D”   See the biofilm movie below on the Philips Sonicare® Toothbrush.       _________________________________________   Education     Undergraduate Scholarship Program Awards   Six students were awarded undergraduate scholarships for the 2002-2003 academic year, to work on the following CBE biofilm-related research projects.  The project titles and student information are listed below.   Effectiveness of chloramines used as the recharge biocide on rechargeable biocidal surfaces Student: Wesley Bauman (Civil Engineering); Mentor: Anne Camper   Microbial fuel cells Student: Sarah Golden (Biological Sciences); Mentor: Haluk Beyenal   Spatial patterns of killing in Pseudomonas aeruginosa biofilms Student: Amber Harrer (Chemical Engineering); Mentor: Phil Stewart   Leukocyte response to biofilms Student: Jeremy Mitchell (Chemical Engineering); Mentor: Mark Shirtliff   Reproducible Pseudomonas aeruginosa biofilms Student: Deanne Stookey (Biological Sciences); Mentor: Haluk Beyenal   Spatial patterns of growth in Pseudomonas aeruginosa biofilms Student: Erin Werner (Chemical Engineering); Mentor: Phil Stewart     _________________________________________   Visitors   Giorgia Borriello is a new member of the Biofilm Control lab group.  Giorgia is a visiting microbiology graduate student from Federico II University in Naples, Italy. While she is at the CBE, Giorgia will be learning biofilm science techniques, including molecular protocols and confocal laser scanning microscopy.   _______   Dr. John "Jack" Marburger, Science Adviser to the President and Director of the Office of Science and Technology Policy, visited the Center October 18, 2002.  It was a special occasion for us to host such a distinguished guest, and we did our best to introduce him to our excitement about biofilms.     _________________________________________   Upcoming CBE Workshop   The CBE offered a Biofilm Methods workshop on November 18-19, 2002,  (Monday-Tuesday) in Bozeman, Montana, USA. The workshop covered: - analysis and repeatability of biofilm measurements - aseptic technique - biofilm reactor design considerations - four stages of biofilm study (growth, sampling, treatment, analysis) - reactor protocols (set up, inoculation, treatment) - anaerobic reactor design and operation - microscopy for biofilm enumeration - using fluorescent in-situ hybridization (FISH) probes to study biofilms, and - biosafety instruction. The cost of the 2-day workshop was $1500.  If you are interested in more information about  the workshop, please contact Paul Sturman (paul_stu@erc.montana.edu).     _________________________________________   CBE People in Action   Paul Stoodley was an invited speaker at the 30th Congress of the Italian Society of Microbiology - Catania, Italy, October 6-8, 2002.  He presented “The Formation and Dynamic Behaviors of Bacterial Biofilm.”  This was the first time that the Italian Society for Microbiology had a specific section on Biofilms and this section was organized by Professor Stefania Stefani. Paul’s opening talk introduced the topic to a group consisting of mainly medical microbiologists and immunologists.   Marty Hamilton as an invited speaker presented, "Comparison of Available Test Methodologies" at the Interagency Working Meeting – Test Methods and Surrogates for Anthrax, Washington, DC, October 9-10, 2002.   Mark Shirtliff was invited to present, “Proteomics, Genomics, and Host-Pathogen Interactions in Staphylococcus aureus Biofilms,” Department of Microbiology, Montana State University-Bozeman, October 11, 2002.   Thomas Borch presented “Characterization of Two Iron Oxide Models for Environmental Research: Microscopic and Spectroscopic Studies,” and also a poster entitled “Use of High Performance Liquid Chromatography - Diode Array Detection for the Improved Analysis of 2,4,6-Trinitrotoluene and Its Reduced Metabolites” at the Subsurface Science Symposium, Boise, Idaho, October 12-16, 2002.   Zbigniew Lewandowski, presented “Mapping Toxic Shock Syndrome Toxin-1 (TSST-1) Expression in a Biofilm of Staphylococcus aureus using TSST-1-yfpTM Reporter Strain and a yfp-Sensitive Fiber-Optic Sensor,” at the 10th International Symposium on Staphylococci and Staphylococcal Infections, Tsukuba. Japan, October 16-19, 2002.   Bill Costerton was invited to give a presentation to the Heart Valve Therapy Research Group, Edwards Lifesciences, Irvine, California, October 25, 2002.   He presented "Biofilm Organization, Testing, and Research."      Bill Costerton was invited to talk about "Taming Microbial Biofilms," at the Council for Advancement of Science Writing, Inc. (CASW) Fortieth Annual Briefing:  New Horizons in Science, St. Louis, Missouri, October 26-28, 2002.  This is a briefing to office science writers with the background perspective and context needed to help them better understand and interpret new and future developments in the frontier areas of science and technology and to deliver a program that satisfies their immediate need, in response to their editors' demands, for "spot" news (as in new --- new discoveries, new solutions, new conclusions, new applications that have not yet been widely reported) geared to the general public.     __________________________________________   Theses   See theses abstracts at http://www.erc.montana.edu/Res-Lib99-SW/pubs/Theses/default.htm     __________________________________________   Web Watch   Biofilm Movie:  Philips Sonicare® Toothbrush   This web page provides movies showing the effect of powered toothbrushing by Philips Sonicare® toothbrush on a Streptococcus mutans biofilm.   See http://www.erc.montana.edu/Res-Lib99-SW/Movies/2002/02-M010_M013.htm   _______   BiofilmsOnline.com   See the BiofilmsOnline.com November issue at http://www.BiofilmsOnline.com.   _______   Recent Web Updates   Check the Recent Web Updates link located on the CBE home page, to view the latest information posted 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