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Pictures E-coli on glass. Frames taken by phase contrast microscopy utilizing fluorescent dye (white) to indicate microbial membrane permeability resulting from bacterial death |
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Surfacine treated glass (start) |
Control untreated glass (start) |
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Surfacine treated glass (90 minutes) |
Control untreated glass(90 minutes) |
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| Movie (side-by-side comparison) | Download AVI movie (1.7M) |
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| How was it done? | |
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Ten microliters of log phase culture of E. coli (in TSB) was placed onto either a Surfacine-coated 22 x 40mm glass coverslip or an untreated control coverslip. A disc of agarose (2mm thick X 10mm in diameter), infused with tryptic soy broth containing 0.84mM SYTO 9 dye (Molecular Probes), was placed atop the bacteria. SYTO 9 collects in dead bacteria after its cell walls degrade. A 15mm coverslip was placed atop the agarose, excess media removed by blotting and the entire prep - agarose between two coverslips - was sealed with melted paraffin and petroleum jelly. The sealed prep was mounted on the stage of a Nikon Microphot maintained at 37 degrees C and viewed using a 100x phase contrast oil immersion lens. Video from an Optronics DEI 750 3-chip color CCD was captured as individual time-lapse frames at 3 second intervals on a Macintosh G3 computer. At every 100th frame (every 5 minutes), phase contrast illumination was blocked, and a fluorescence image captured. Fluorescence frames (shown in white) were morphed to show the relative time-course of bactericidal activity of Surfacine and superimposed on the phase contrast frames. |
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| Who did it? | |
| Microscopy by Jim Sullivan, www.cellsalive.com |