FtsY is predominantly membrane bound in vivo. (A) Wild-type Escherichia coli cells carrying different FtsY-green fluorescent protein derivatives as described in Figure. 4 were analysed by fluorescence microscopy. The upper panel displays the original image and the lower panel a processed image after a three dimensional deconvolution of Z-stacks. (B) The localization of FtsY and the integral membrane protein SecY were analysed in wild-type E. coli cells containing only the endogenous amounts of FtsY and SecY. For this purpose, immune-fluorescence was carried out using polyclonal SecY and FtsY antibodies and Alexa fluor 555 labelled secondary antibodies. (C) Bacillus subtilis cells expressing FtsY-YFP as sole source of the protein growing exponentially; foci along the lateral cell membrane are indicated by white triangle. White bar 2 μm.
Mircheva et al. BMC Biology 2009 7:76 doi:10.1186/1741-7007-7-76