Center for Biofilm Engineering

News Update: 

June, 2003

Volume 6, Issue 6

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Research Highlights

Paper Spotlight by Haluk Beyenal

Pseudomonas aeruginosa is often used in biofilm studies and in modeling biofilm accumulation, probably because microbial geneticists have been studying this organism intensively, and its physiology and genetics are well known. Biokinetic parameters for microbial growth of Pseudomonas aeruginosa have been previously determined at relatively low glucose concentrations, less than 7.5 mg/L in the chemostat, and less than 1.4 mg/L in the biofilm reactor. The reason for using such low glucose concentrations was to assure that glucose, not oxygen, was the limiting substrate. In biofilms, however, there is little control over the substrates that may act as growth-limiting factors. Concentrations of electron donors and electron acceptors in biofilms decrease toward the bottom because of mass transfer limitations and microbial consumption; it may be difficult to assess which of them is exhausted first in the deeper biofilm layers. With an excess of glucose in solution, it is reasonable to assume that oxygen rather than glucose will be the growth-limiting factor. However, to quantify biofilm accumulation rate, models accounting for multiple-substrate utilization by the microorganisms should be used to judge whether the electron donor or the electron acceptor is the growth-limiting factor. To our best knowledge, there are not any available multiple-substrate growth kinetic models developed for Pseudomonas aeruginosa. The goal of this study was to develop such a model and to calculate biokinetic parameters associated with the model.

Growth parameters of Pseudomonas aeruginosa (ATCC 700829) were quantified based on steady state concentrations, utilization rates of glucose and dissolved oxygen, and microorganism concentration in a chemostat that was operated at 25^oC, pH = 7.2, and an agitation rate 350 rpm. The results showed that the microbial growth was limited by the concentration of glucose and by the concentration of oxygen. A dual-substrate, Tessier growth kinetics for oxygen and glucose, was in good agreement with the experimental data using the following biokinetic parameters: µmax = 0.29 h^-1, K_g = 26.9 mg/L, K_o = 1.18 mg/L, Y_x/g = 0.628 (g microorganism/g glucose) and, Y_x/o = 0.635 (g microorganism/g oxygen). Maintenance factors for glucose and oxygen were: m_g=0.0078 g glucose consumed/g microorganism.hour, and m_o=0.014 g oxygen consumed/g microorganism hour. The calculated biokinetic parameters will be used to compare biofilm and planktonic type growth of Pseudomonas aeruginosa (ATCC 700829).

Beyenal, H., S.N. Chen and Z. Lewandowski, "The Double Substrate Growth Kinetics of Pseudomonas aeruginosa," Enzyme Microbial Tech., 32(1):92-98 (2003).

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Upcoming Technical Advisory Conference and Workshops

The Summer 2003 Technical Advisory Conference (TAC) will be held in Bozeman, MT, July 22-24, 2003. The TAC Agenda can be viewed and downloaded as a pdf file at this address: http://www.erc.montana.edu/Ind-Col99-SW/IAP/tac/TAC_FormtdAgenda_summer03.pdf

These workshops will be offered to Industrial Associate members:

Biofilm Methods Workshop
July 21, 2003
To register, contact Paul Sturman (paul_stu@erc.montana.edu).

Advanced Biofilm Methods Workshop
July 21, 2003
To register, contact Paul Sturman (paul_stu@erc.montana.edu).
 

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Grant Announcement

Paul Stoodley received a grant with Philips Oral Health Care entitled “Rheology of Dental Plaque Biofilms,” for over $39,000. The project will be funded 4/1/03 through 12/31/03.

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Collaborative Research

Robin Gerlach spent three months (January 20th through April 25th, 2003) at the INEEL in Idaho Falls to run a Mesoscale Column Study investigating the direct and indirect reduction of Cr(VI) in model systems. This study was conducted in collaboration with Bill Apel at the INEEL and Brent Peyton and Sridhar Viamajala from Washington State University.
 

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International Collaborative Workshop

Rick Veeh will be in Rome from June 22nd through July 3rd teaching a workshop on various molecular techniques for application to biomedical and health issues. This workshop was arranged by Bill Costerton through CBE colleagues Marcos Artini and Laura Selan, at the University of Rome "La Sapienza". This course is intended to open collaborations between the two universities.

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Media Coverage

Biofilms in Medicine, Industry and Environmental Biotechnology
edited by Piet Lens, Anthony P. Moran, Therese Mahony, Paul Stoodley and Vincent O’Flaherty

This book offers a holistic and multi-disciplinary description of the topic, including biofilm formation and composition, but also biofilm monitoring, disinfection and control. All these aspects are presented from three points of views: medical, industrial and environmental biotechnological in a compact, easy to read format. For more information and to order online, go to http://www.iawq.org.uk/

Chapters authored by Center researchers include:
“The role of cell signalling in biofilm development,” by B.L. Purevdorj and P. Stoodley
“Use of flow cells and annular reactors to study biofilms,” by P. Stoodley and B.K. Warwood
“Use of microsensors to study biofilms,” by Z. Lewandowski and H. Beyenal

Cover images were provided by Paul Stoodley, Suzanne Wilson, Peg Dirckx and also Dirk deBeer of the Max Planck Institute for Marine Microbiology, Bremen, Germany

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Bioglyphs: Art and Bioluminescence Combined
This article is adapted from “Scientists Create Bonds with Artists” which was first published in the Analytical Chemistry A-pages on April 1, 2003. It appeared on www.chemistry.org on May 12, 2003.

http://www.chemistry.org/portal/a/c/s/1/feature_ent.html?id=3aa45e10816711d7fc3d6ed9fe800100

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Nature Biotechnology recently published an article on the biotechnology of biofilms. The Center, several associate companies, and collaborators were prominently featured in the article. This is an excellent article for readers who do not have a strong science background.

Slimy business—the biotechnology of biofilms
Schachter B
Nature Biotechnology Apr 2003; 21:361-365

This article can be viewed at http://www.nasw.org/users/bschachter/writing.html

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Education

Summer 2003 REU Program

The Research Experience for Undergraduates program got underway June 9th and will continue through August 15th. Eight students began the ten-week program with a week of lab tours and workshops to orient them to the Center. Listed below are the students, their projects, and project mentors.

Transcription profiling of Staphylococcus aureus biofilms through microarray analysis
REU Student: Megan Falsetta
Mentor: Dr. Mark Shirtliff

Design of a mobile biofilm microscopy unit
REU Student: Paul Gentile
Mentor: Dr. Paul Stoodley

Develop a protocol for reproducible biofilms that are found in the oral cavity
REU Student: Megan Halliburton
Mentors: Dr. Mark Pasmore & Melvin Czechowski, Ph.D. (Church & Dwight Co., Inc.)

Antimicrobial surfaces based on immobilized enzymes
REU Student: Aana Moon Kim
Mentor: Dr. Phil Stewart

Analyses of biofilm by QC M-D
REU Student: Charles McCartney
Mentor: Dr. Mark Pasmore

Hydrogenobaculum population diversity in biofilm communities inhabiting acidic geothermal springs in Yellowstone National Park
REU Student: Colin McWilliams
Mentor: Dr. Timothy McDermott

Microbial fuel cell
REU Student: Adam Vawter
Mentors: Dr. Zbigniew Lewandowski & Dr. Haluk Beyenal

Evaluation of Fe(III) chelates for catalytic hydrogen peroxide oxidation of Pseudomonas aeruginosa biofilm
REU Student: Jennifer Warren
Mentor: Dr. James Duffy

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Upcoming CBE Workshops

Biofilm Image Analysis Workshop

July 10-11, 2003
Registration: see

http://www.erc.montana.edu/CBEssentials-SW/whats_new/workshops.htm

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Biofilm Methods Workshop (for Industrial Associate members)
 

July 21, 2003
Registration: contact Paul Sturman (paul_stu@erc.montana.edu)

Advanced Biofilm Methods Workshop (for Industrial Associate members)
 

July 21, 2003
Registration: contact Paul Sturman (paul_stu@erc.montana.edu)

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Microsensors Workshop

August 11-15, 2003
Registration: see http://www.erc.montana.edu/CBEssentials-SW/whats_new/workshops.htm
 

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Biofilm Methods Workshop
 

October 20-21, 2003
The workshop will cover:
- 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 two-day workshop is $1500. If you are interested in more information about the workshop, please contact Paul Sturman (paul_stu@erc.montana.edu).
 

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CBE People in Action

Robin Gerlach presented "Biofilm-Based Technologies for Mixed Waste Remediation" at a workshop from the Army Research Office in Cashiers, NC, April 29, 2003.

Robin Gerlach presented "Direct and Indirect Cr(VI) Reduction by Cellulomonas spp. – Batch Kinetics and Meso-Scale Tests," at the PNNL in Richland, WA, May 9, 2003.

Anne Camper gave a general presentation on biofilms in water systems to Edstrom Industries’ sales staff. This was followed by a presentation containing information that could be used by sales staff when discussing their animal watering systems, May 20, 2003.

Darla Goeres as an invited speaker presented "Bacterial Biofilms: An Update on Methods Appropriate for Growth, Germicide Treatment & Analysis,” at the Consumer Specialty Products Association (CSPA) meeting in Chicago, May 8, 2003.

Marty Hamilton and Darla Goeres were invited by the Montana Research and Commercialization Board to present the final results of a two-year project to develop a biofilm reactor system and associated standard operating procedure suitable for growing a repeatable biofilm under shear and continuous flow. The reactor chosen for this purpose was the CDC Biofilm Reactor, originally designed by Rod Donlan and Ricardo Murga of the Center for Disease Control and Prevention (CDC). The work was done in collaboration with Bryan Warwood of BioSurface Technologies, Bozeman, MT. Marty and Darla’s presentation was given May 21, 2003.

Bill Costerton gave an invited presentation, "Biofilms," at the Third Annual Podiatry Conference, Pittsburgh, PA, May 30-31, 2003.

Thomas Borch presented "2,4,6-Trinitrotoluene (TNT) Biodegradation by a Novel Gram-Positive Iron-Reducing Bacterium," at the 7th International Symposium on In Situ and On Site Bioremediation" in Orlando, FL, June 2-5, 2003.

Robin Gerlach presented "Direct and Indirect Cr(VI) Reduction by Cellulomonas spp. – Batch kinetics and meso-scale tests," at the 7th International Symposium on In Situ and On Site Bioremediation" in Orlando, FL, June 2-5, 2003.

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Biofilm Movies and Publications

See Biofilm Movies at
http://www.erc.montana.edu/Res-Lib99-SW/Movies/Database/MD_DisplayScript.asp

See Publications at
http://www.erc.montana.edu/Res-Lib99-SW/pubs/Database/PD_DisplayScript.asp

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See the BiofilmsOnline.com June issue at http://www.BiofilmsOnline.com.

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Biofilms Journal

Announcement and Call for Papers
See http://www.erc.montana.edu/Res-Lib99-SW/newsarchives/Biofilms%20Journal/default.htm

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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> 

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