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P.858 right column 2nd paragraph:"By using FRAP [fluorescent recovery after photobleaching] [investigators] determined the diffusion coefficient of GFP and β-galactosidase-GFP in the cytoplasm of L. lactis (Fig. 1A). The measurements were performed on cells in a chemically defined growth medium (CDMRP, see Experimental procedures) or in phosphate-based media. In Fig. 2A, [they] observe that for any given condition the diffusion of GFP is characterized by a broad spread in D values (from about sevenfold to more than two orders of magnitude). In non-stressed cells, the median of the diffusion coefficient of GFP is 7 μm^2 s^−1 for cells in CDMRP (Fig. 2A, black bars, top panel, Table S1) and 4.3 μm^2 s^−1 for cells resuspended in phosphate-based medium with the same osmolality as CDMRP (Fig. 2A, grey bars, top panel, Table S1). These values are in the same range as those reported for E. coli: 3–14 μm^2 s^−1 (Konopka et al., 2007 2009 Mika and Poolman, 2011a). The expression levels of β-galactosidase-GFP were lower than for GFP and some cells contained aggregates cells with visible aggregates were not included in the analysis. The overall Dmedian of two independent data sets was 0.77 μm^2 s^−1 (number of cells, Ncells = 53, see Table S2), which is similar to the value measured previously in E. coli: Dmedian of 0.68 μm^2 s^−1 (Mika et al., 2010)." See notes beneath table |