MurG point mutants delocalize from the forespore and affect sporulation. (A) (left) An 18 amino
acid region from the MurG N-terminal patch SFENVKTVMRFLKGVKKS predicted to be a membrane-
binding interface also forms an amphipathic helix as predicted by the program Heliquest. Position of
residues mutated to glutamic acid are shown. Charged residues are shown in blue, non-polar residues are
shown in yellow and uncharged residues are shown in pink. Adjacent residues are connected by a gray
line, letters N and C in red show the start and end of the sequence. (right) A sequence alignment of the
same 18-amino acid region between B. subtilis and E. coli. Similar residues are denoted with an asterisk
(*). (B) Fluorescence images of MurG-GFP mutants (green) in a DmurG background merged with FM4-
64 (red) at T4 of sporulation, the mutations performed on murG are shown in top left corner. Note V74E
and F77E mutants are blocked in engulfment at the septation stage. (C) Engulfment assay showing the
percentage of cells sporulated over time on murG point mutants in a DmurG background compared to
wild type and cardiolipin-less strain. Strains are in black wild type murG (JDB2501), violet murG(S67E)
(JDB2601), green murG(V74E) (JDB2552), orange murG(F77E) (JDB2559), blue murG(V81E)
(JDB2602), and red Dcard (JDB2238). Strain murG(M75E) is (JDB2542). D. Table showing forespore to
mother cell fluorescence ratio of MurG-GFP point mutants during sporulation.(For interpretation of the
references to color in this figure legend, the reader is referred to the web version of this article.)