Variance reducing and noise correction in protein quantification by measuring fluctuations in fluorescence due to photobleaching.

Quantifying the absolute protein number using the ratio between the variance and the mean of the protein Fluorescence intensity is a straightforward method for microscopy imaging. Recently, this method has been expanded to fluorescence decaying processes due to photobleaching with binomial distribution. The article examines the method proposed and shows how it can be adapted to the case of variance in the initial number of proteins between the cells.

Stochastic nucleoid segregation dynamics as a source of the phenotypic variability in E. coli.

Segregation of the replicating chromosome from a single to two nucleoid bodies is one of the major processes in growing bacterial cells. The segregation dynamics is tuned by intricate interactions with other cellular processes such as growth and division, ensuring flexibility in a changing environment. We hypothesize that the internal stochasticity of the segregation process may be the source of cell-to-cell phenotypic variability, in addition to the well-established gene expression noise and uneven partitioning of low copy number components.