Magnetic resonance microscopy of biofilm structure and impact on transport in a capillary bioreactor

Seymour, Joseph D.; Codd, Sarah L.; Gjersing, Erica; Stewart, Philip S.

doi:10.1016/j.jmr.2004.01.009

Cited by 87 publications

(82 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Based upon combined optical laser scanning confocal and NMR microscopy, it provides biomass volume and distributions as well as time-and depthresolved metabolite concentrations in active biofilms for sample volumes on the order of 1 mm 3 . Previous researchers generally employ a standard NMR radial tube geometry with biofilm covering the circumference to study flow and diffusion characteristics of live biofilms Seymour et al, 2004;Gjersing et al, 2005). What makes the current application very unique is the use of a planar perfusion chamber and the application of small-volume spectroscopy techniques to quantify multiple metabolites in a temporal and depthresolved fashion.…”

Section: Discussionmentioning

confidence: 99%

“…The disadvantage of NMR is its inherent low sensitivity due to the low energies involved, requiring careful optimization to reduce measurement times and lower concentration detection thresholds. NMR has been used to measure flow and diffusion in biofilm systems (Lewandowski, 1992 #198;Lewandowski, 1993 #197) (Lewandowski et al, 1995;Vogt et al, 2000;Van As and Lens, 2001;Seymour et al, 2004) as well as planktonic cell metabolism (Shanks, 2001). Previous NMR studies of live prokaryotic cell suspensions, gelimmobilized cells and extracts have provided detailed metabolic information (Junter et al, 2002).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Correlated biofilm imaging, transport and metabolism measurements via combined nuclear magnetic resonance and confocal microscopy

2007

View full text Add to dashboard Cite

Bacterial biofilms are complex, three-dimensional communities found nearly everywhere in nature and are also associated with many human diseases. Detailed metabolic information is critical to understand and exploit beneficial biofilms as well as combat antibiotic-resistant, disease-associated forms. However, most current techniques used to measure temporal and spatial metabolite profiles in these delicate structures are invasive or destructive. Here, we describe imaging, transport and metabolite measurement methods and their correlation for live, non-invasive monitoring of biofilm processes. This novel combination of measurements is enabled by the use of an integrated nuclear magnetic resonance (NMR) and confocal laser scanning microscope (CLSM). NMR methods provide macroscopic structure, metabolic pathway and rate data, spatially resolved metabolite concentrations and water diffusion profiles within the biofilm. In particular, current depth-resolved spectroscopy methods are applied to detect metabolites in 140-190 nl volumes within biofilms of the dissimilatory metal-reducing bacterium Shewanella oneidensis strain MR-1 and the oral bacterium implicated in caries disease, Streptococcus mutans strain UA159. The perfused sample chamber also contains a transparent optical window allowing for the collection of complementary fluorescence information using a unique, in-magnet CLSM. In this example, the entire threedimensional biofilm structure was imaged using magnetic resonance imaging. This was then correlated to a fluorescent CLSM image by employing a green fluorescent protein reporter construct of S. oneidensis. Non-invasive techniques such as described here, which enable measurements of dynamic metabolic processes, especially in a depth-resolved fashion, are expected to advance our understanding of processes occurring within biofilm communities.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Correlated biofilm imaging, transport and metabolism measurements via combined nuclear magnetic resonance and confocal microscopy

2007

View full text Add to dashboard Cite

show abstract

“…Techniques that provide information about the physical structure and chemical properties of biofilms are nuclear magnetic resonance (44), attenuated total reflectance-Fourier transform infrared spectroscopy (7), and photoacoustic spectroscopy (43). Some biofilm monitoring techniques provide information about metabolic activity in biofilms, such as those using electrochemical devices like dissolved oxygen and redox probes (25), microbiologically influenced corrosion monitoring (34), nuclear magnetic resonance (56), measurement of substrate consumption (19,50) or metabolic products (53), bioluminescence assays, and fluorometry (56).…”

mentioning

confidence: 99%

CO ₂ Production as an Indicator of Biofilm Metabolism

Kroukamp

Wolfaardt

2009

Appl Environ Microbiol

View full text Add to dashboard Cite

Biofilms are important in aquatic nutrient cycling and microbial proliferation. In these structures, nutrients like carbon are channeled into the production of extracellular polymeric substances or cell division; both are vital for microbial survival and propagation. The aim of this study was to assess carbon channeling into cellular or noncellular fractions in biofilms. Growing in tubular reactors, biofilms of our model strain Pseudomonas sp. strain CT07 produced cells to the planktonic phase from the early stages of biofilm development, reaching pseudo steady state with a consistent yield of ϳ10 7 cells ⅐ cm ؊2 ⅐ h ؊1 within 72 h. Total direct counts and image analysis showed that most of the converted carbon occurred in the noncellular fraction, with the released and sessile cells accounting for <10% and <2% of inflowing carbon, respectively. A CO 2 evolution measurement system (CEMS) that monitored CO 2 in the gas phase was developed to perform a complete carbon balance across the biofilm. The measurement system was able to determine whole-biofilm CO 2 production rates in real time and showed that gaseous CO 2 production accounted for 25% of inflowing carbon. In addition, the CEMS made it possible to measure biofilm response to changing environmental conditions; changes in temperature or inflowing carbon concentration were followed by a rapid response in biofilm metabolism and the establishment of new steady-state conditions.

show abstract

“…Smaller-diameter RF coils, however, are capable of generating higher resolutions. Indeed, smaller-diameter bespoke RF coils have already been used to examine metabolite production and consumption in biofilms ϳ100 m thick, with a resolution of ϳ20 m (23,37). Evidently, the next step here should be to build smallerdiameter RF coils which will enable the imaging of paramagnetically labeled molecules in thinner biofilms.…”

Section: Discussionmentioning

confidence: 99%

“…Researchers have already used MRI to examine flow dynamics over biofilm surfaces (22,37), metabolite consumption and production (23), the flux of heavy metals in metal-immobilizing bioreactors (15,25), water diffusion in biofilms (28,44), and the transport and fate of metals both in natural and artificial biofilms (28,29) and in real methanogenic granules which are employed in anaerobic wastewater treatment (2).…”

mentioning

confidence: 99%

Application of Paramagnetically Tagged Molecules for Magnetic Resonance Imaging of Biofilm Mass Transport Processes

Ramanan

Holmes

Sloan

et al. 2010

Appl Environ Microbiol

View full text Add to dashboard Cite

Molecules become readily visible by magnetic resonance imaging (MRI) when labeled with a paramagnetic tag. Consequently, MRI can be used to image their transport through porous media. In this study, we demonstrated that this method could be applied to image mass transport processes in biofilms. The transport of a complex of gadolinium and diethylenetriamine pentaacetic acid (Gd-DTPA), a commercially available paramagnetic molecule, was imaged both in agar (as a homogeneous test system) and in a phototrophic biofilm. The images collected were T 1 weighted, where T 1 is an MRI property of the biofilm and is dependent on Gd-DTPA concentration. A calibration protocol was applied to convert T 1 parameter maps into concentration maps, thus revealing the spatially resolved concentrations of this tracer at different time intervals. Comparing the data obtained from the agar experiment with data from a one-dimensional diffusion model revealed that transport of Gd-DTPA in agar was purely via diffusion, with a diffusion coefficient of 7.2 ؋ 10 ؊10 m 2 s ؊1 . In contrast, comparison of data from the phototrophic biofilm experiment with data from a twodimensional diffusion model revealed that transport of Gd-DTPA inside the biofilm was by both diffusion and advection, equivalent to a diffusion coefficient of 1.04 ؋ 10 ؊9 m 2 s ؊1 . This technology can be used to further explore mass transport processes in biofilms, either by using the wide range of commercially available paramagnetically tagged molecules and nanoparticles or by using bespoke tagged molecules.

show abstract

Magnetic resonance microscopy of biofilm structure and impact on transport in a capillary bioreactor

Cited by 87 publications

References 23 publications

Correlated biofilm imaging, transport and metabolism measurements via combined nuclear magnetic resonance and confocal microscopy

Correlated biofilm imaging, transport and metabolism measurements via combined nuclear magnetic resonance and confocal microscopy

CO ₂ Production as an Indicator of Biofilm Metabolism

Application of Paramagnetically Tagged Molecules for Magnetic Resonance Imaging of Biofilm Mass Transport Processes

Contact Info

Product

Resources

About

Magnetic resonance microscopy of biofilm structure and impact on transport in a capillary bioreactor

Cited by 87 publications

References 23 publications

Correlated biofilm imaging, transport and metabolism measurements via combined nuclear magnetic resonance and confocal microscopy

Correlated biofilm imaging, transport and metabolism measurements via combined nuclear magnetic resonance and confocal microscopy

CO 2 Production as an Indicator of Biofilm Metabolism

Application of Paramagnetically Tagged Molecules for Magnetic Resonance Imaging of Biofilm Mass Transport Processes

Contact Info

Product

Resources

About

CO ₂ Production as an Indicator of Biofilm Metabolism