Sporulation in sinRR’ mutant.

(A) Phase contrast microscopy of paraformaldehyde-fixed R20291::sinRR’ strains revealed no spores. (B) R20291::sinRR’ was asporogenic as shown in representative TEM images in comparison with the parent strain. Black arrows indicate mature spores in parent strains. C. Asporulation phenotype of sinRR’ mutant could not be complemented. Sporulation frequency (CFU/ml of ethanol resistant spores) of R20291, sinRR’ mutant and mutant complemented with different constructs were determined. The sinRR’ mutant strain expressing spo0A from its own promoter was also included in this analysis. Below the sporulation frequency graph is the multiplex-western blot analysis of sinRR’ mutant complemented strain proteins using Spo0A and GDH specific antibodies.