Supplemental Information: Entropy-driven motility of Sinorhizobium meliloti on a semi-solid surface
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چکیده
The experimental apparatus for time-lapse fluorescence imaging of spreading S. meliloti was described in [1]. The agar plate with the spreading S. meliloti was imaged through a 2× achromatic lens (MAP1075150-A, ThorLabs) and (for fluorescence) a GFP emission filter (MF525-39, ThorLabs) onto a cooled, 1300 × 1030 CCD array (Princeton Instruments). Images were collected at a rate of 0.001 Hz for (typically) 70 h. We used a white-light imaging system to measure the effect of agar concentration on the rate of (purified) EPSII spreading. Here the EPSII concentrate was deposited onto an agar slab and imaged under white LED illumination by an f = 8 mm lens onto a 1024× 768, CCD array (Imaging Source) at 0.004 Hz for 12 h.
منابع مشابه
Entropy-driven motility of Sinorhizobium meliloti on a semi-solid surface.
Sinorhizobium meliloti growing on soft agar can exhibit an unusual surface spreading behaviour that differs from other bacterial surface motilities. Bacteria in the colony secrete an exopolysaccharide-rich mucoid fluid that expands outward on the surface, carrying within it a suspension of actively dividing cells. The moving slime disperses the cells in complex and dynamic patterns indicative o...
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A successful symbiotic relationship between Sinorhizobium meliloti and its host Medicago sativa (alfalfa) depends on several signaling mechanisms, such as the biosynthesis of exopolysaccharides (EPS) by S. meliloti. Previous work in our laboratory has shown that a quorum-sensing mechanism controls the production of the symbiotically active EPS II. Recent microarray analysis of the whole-genome ...
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