infrared differential interference contrast (ir-dic) and fluorescence imaging  (Carl Zeiss)

Journal: PLoS ONE

Article Title: Protein Aggregation in E. coli : Short Term and Long Term Effects of Nutrient Density

doi: 10.1371/journal.pone.0107445

Figure Lengend Snippet: (n = 200±20 each for data in Fig. 2A to C). A: The proportion of aggregate free cells: Both short term exposure and long term selection in low nutrient concentrations increased the proportion of aggregate free cells. (chi sq = 38.15, p<0.0001). B: The mean fluorescence intensities of cells (expressed relative to mean Wh including aggregate free cells) under the 6 selection nutrition combinations: The grey columns denote the average including cells without visible aggregates. The black columns denote average calculated by excluding the aggregate free cells. *denotes significant difference from Wh. $ denotes significant difference between corresponding h and l conditions (at p<0.05). C: Frequency distribution of cells with fluorescence intensity classes of aggregates: The modal class is 1 except in Lh and Ll where the modal class is 0. The proportion of cells in different intensity classes across the three selection lines differed significantly at high nutrient concentration (for Wh, Hh and Lh Chi square = 57.157, df = 6, P<0.0001) as well as low nutrient concentration (For Wl , Hl and Ll Chi square = 35.317, df = 6, P<0.0001). The effect of current nutrient concentration was not significant for W (Chi square = 2.35, df = 3, P = 0.503) but was significant for H (Chi square = 7.138, df = 3, P = 0.0676) and L (Chi square = 9.415, df = 3, P = 0.0243).

Article Snippet: Observations were made using differential interference contrast (DIC) and fluorescence imaging on Zeiss Axioimager M-1 upright microscope (100X/1.40 Oil DIC M27) with a color digital camera controlled by Axio software 4.8.

Techniques: Selection, Fluorescence, Concentration Assay

Journal: PLoS ONE

Article Title: Protein Aggregation in E. coli : Short Term and Long Term Effects of Nutrient Density

doi: 10.1371/journal.pone.0107445

Figure Lengend Snippet: (A) and after starvation for 4 days (B). The scale bar represents 20 µ. Inset: some of the larger aggregates did not disappear after prolonged starvation (30 days) but altered the morphology showing diffused fluorescence sometimes even exceeding the cell boundary.

Article Snippet: Observations were made using differential interference contrast (DIC) and fluorescence imaging on Zeiss Axioimager M-1 upright microscope (100X/1.40 Oil DIC M27) with a color digital camera controlled by Axio software 4.8.

Techniques: Fluorescence

Journal: PLoS ONE

Article Title: Protein Aggregation in E. coli : Short Term and Long Term Effects of Nutrient Density

doi: 10.1371/journal.pone.0107445

Figure Lengend Snippet: (n = 100±20 each for data in ). A and B: The mean fluorescence intensities before (grey bars) and after (black bars) starvation for 4 days. Means calculated excluding (A) and including (B) aggregate free cells. All columns are significantly reduced in B but not reduced or significantly increased in A. This suggests that all aggregate classes are not degraded proportionately. Many of the larger ones could be relatively resistant to degradation while the smaller ones degrade fast, thereby increasing the mean excluding aggregate free cells after degradation. *denotes significant difference from Wh. $ denotes significance between corresponding starved and unstarved populations (at p<0.05). C: The time course of decrease in the mean fluorescence intensity with starvation: The intensities are expressed relative to the mean intensity at zero hours. p: represents mean excluding aggregate free cells and q: represents including them in continued stationary phase. r: represents averages excluding aggregate free cells and s: represents including aggregate free cells in distilled water. Error bars show standard error of the mean.

Article Snippet: Observations were made using differential interference contrast (DIC) and fluorescence imaging on Zeiss Axioimager M-1 upright microscope (100X/1.40 Oil DIC M27) with a color digital camera controlled by Axio software 4.8.

Techniques: Fluorescence