This work was funded by the Max Planck society.

<ol>
	<li>Axelrod, D., Thompson, N. L., Burghardt, T. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+internal+inflection+fluorescent+microscopy.">Total internal inflection fluorescent microscopy.</a> J. Microsc. 129, 19-28 (1983).</li><li>Axelrod, D., Omann, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combinatorial+microscopy.">Combinatorial microscopy.</a> Nat. Rev. Mol. Cell Biol. 7, 944-952 (2006).</li><li>Axelrod, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+imaging+of+surface+fluorescence+with+very+high+aperture+microscope+objectives.">Selective imaging of surface fluorescence with very high aperture microscope objectives.</a> J. Biomed. Opt. 6, 6-13 (2001).</li><li>Dominguez-Escobar, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Processive+movement+of+MreB-associated+cell+wall+biosynthetic+complexes+in+bacteria.">Processive movement of MreB-associated cell wall biosynthetic complexes in bacteria.</a> Science. 333, 225-228 (2011).</li><li>Sparkes, I. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bleach+it,+switch+it,+bounce+it,+pull+it:+using+lasers+to+reveal+plant+cell+dynamics.">Bleach it, switch it, bounce it, pull it: using lasers to reveal plant cell dynamics.</a> J. Exp. Bot. 62, 1-7 (2011).</li><li>Uchida, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+synthesis+and+absolute+configuration+of+avenolide,+extracellular+factor+in+Streptomyces+avermitilis.">Total synthesis and absolute configuration of avenolide, extracellular factor in Streptomyces avermitilis.</a> J. Antibiot. (Tokyo). , (2011).</li><li>Yu, H., Wedlich-Soldner, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+actin+dynamics:+Generating+randomness+by+formin(g)+and+moving.">Cortical actin dynamics: Generating randomness by formin(g) and moving.</a> Bioarchitecture. 1, 165-168 (2011).</li><li>Yu, J. H., Crevenna, A. H., Bettenbuhl, M., Freisinger, T., Wedlich-Soldner, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+actin+dynamics+driven+by+formins+and+myosin+V.">Cortical actin dynamics driven by formins and myosin V.</a> J. Cell. Sci. 124, 1533-1541 (2011).</li><li>Berchtold, D., Walther, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TORC2+plasma+membrane+localization+is+essential+for+cell+viability+and+restricted+to+a+distinct+domain.">TORC2 plasma membrane localization is essential for cell viability and restricted to a distinct domain.</a> Mol. Biol. Cell. 20, 1565-1575 (2009).</li><li>Vizcay-Barrena, G., Webb, S. E., Martin-Fernandez, M. L., Wilson, Z. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subcellular+and+single-molecule+imaging+of+plant+fluorescent+proteins+using+total+internal+reflection+fluorescence+microscopy+(TIRFM).">Subcellular and single-molecule imaging of plant fluorescent proteins using total internal reflection fluorescence microscopy (TIRFM).</a> J. Exp. Bot. 62, 5419-5428 (2011).</li></ol>

No conflicts of interest declared.

TIRF microscopy is the technique of choice to image peripheral proteins. The low penetration depth of the evanescent field minimizes of out of focus light, which leads to a very good signal to noise ratio and allows data acquisition with high frame rates, or imaging of very weakly expressed proteins. The combination of high contrast and high frame rates makes TIRF microscopy a perfect tool for imaging spatio-temporal dynamics of cortically localized proteins. Interestingly the thick cell wall surrounding many microorgani...

<table border="1">
 <tbody>
 <tr>
 <td>Name of the tool/reagent</td>
 <td>Type</td>
 <td>Company</td>
 <td>Catalogue number</td>
 </tr>
 <tr>
 <td>Orbital Shaker</td>
 <td>Tool</td>
 <td>UniEquip</td>
 <td>UNITWIST 3-D ROCKER SHAKER</td>
 </tr>
 <tr>
 <td>TIRF microscope</td>
 <td>Till</td>
 <td>&nbsp;</td>
 <td>Customized setup</td>
 </tr>
 <tr>
 <td>Glass container </td>
 <td>Tool</td>
 <td>Vitlab</td>
 <td>340-232880353</td>
 </tr>
 <tr>
 <td>Ceramic staining rack</td>
 <td>Tool</td>
 <td>Thomas Sci.</td>
 <td>8542E40</td>
 </tr>
 <tr>
 <td>Concanavalin A</td>
 <td>Reagent</td>
 <td>Sigma</td>
 <td>L7647</td>
 </tr>
 <tr>
 <td>Coverslips #1(18 x 18 mm)</td>
 <td>Microscope</td>
 <td>Menzel Gl&auml;ser</td>
 <td>BB018018A1</td>
 </tr>
 <tr>
 <td>Microscope Slides</td>
 <td>Microscope</td>
 <td>Menzel Gl&auml;ser</td>
 <td>AA00000102E</td>
 </tr>
 <tr>
 <td>Immersion Oil</td>
 <td>Microscope</td>
 <td>Zeiss</td>
 <td>Immersol 518F</td>
 </tr>
 <tr>
 <td>Agarose</td>
 <td>Reagent</td>
 <td>Invitrogen</td>
 <td>16500-500</td>
 </tr>
 <tr>
 <td>FluoSpheres</td>
 <td>Reagent</td>
 <td>Invitrogen</td>
 <td>F8795</td>
 </tr>
 </tbody>
</table>

visualization of cortex organization and dynamics in microorganisms, using total internal reflection fluorescence microscopy

TIRF microscopy has emerged as a powerful imaging technology to study spatio-temporal dynamics of fluorescent molecules in vitro and in living cells1. The optical phenomenon of total internal reflection occurs when light passes from a medium with high refractive index into a medium with low refractive index at an angle larger than a characteristic critical angle (i.e. closer to being parallel with the boundary). Although all light is reflected back under such conditions, an evanescent wave is created that propagates across and along the boundary, which decays exponentially with distance, and only penetrates sample areas that are 100-200 nm near the interface2. In addition to providing superior axial resolution, the reduced excitation of out of focus fluorophores creates a very high signal to noise ratios and minimizes damaging effects of photobleaching2,3. Being a widefield technique, TIRF also allows faster image acquisition than most scanning based confocal setups.
At first glance, the low penetration depth of TIRF seems to be incompatible with imaging of bacterial and fungal cells, which are often surrounded by thick cell walls. On the contrary, we have found that the cell walls of yeast and bacterial cells actually improve the usability of TIRF and increase the range of observable structures4-8. Many cellular processes can therefore be directly accessed by TIRF in small, single-cell microorganisms, which often offer powerful genetic manipulation techniques. This allows us to perform in vivo biochemistry experiments, where kinetics of protein interactions and activities can be directly assessed in living cells.
We describe here the individual steps required to obtain high quality TIRF images for Saccharomyces cerevisiae or Bacillus subtilis cells. We point out various problems that can affect TIRF visualization of fluorescent probes in cells and illustrate the procedure with several application examples. Finally, we demonstrate how TIRF images can be further improved using established image restoration techniques.

Watch this Scientific Journal Video about Visualization of Cortex Organization and Dynamics in Microorganisms, using Total Internal Reflection Fluorescence Microscopy at JoVE.com

Visualization of Cortex Organization and Dynamics in Microorganisms, using Total Internal Reflection Fluorescence Microscopy

Total Internal Reflection Fluorescence (TIRF) microscopy is a powerful approach to observe structures close to the cell surface at high contrast and temporal resolution. We demonstrate how TIRF can be employed to study protein dynamics at the cortex of cell wall-enclosed bacterial and fungal cells.

TIRF microscopy has emerged as  a powerful imaging technology to study spatio-temporal dynamics of fluorescent molecules  in vitro and in living cells1. ...

visualization-cortex-organization-dynamics-microorganisms-using-total

Research

JoVE Journal

Bioengineering

11.4K Views.  Max Planck Institute of Biochemistry. Total Internal Reflection Fluorescence (TIRF) microscopy is a powerful approach to observe structures close to the cell surface at high contrast and temporal resolution. We demonstrate how TIRF can be employed to study protein dynamics at the cortex of cell wall-enclosed bacterial and fungal cells.