Fig. 7

Transmission electron micrographs of C. pasteurianum after 5 days in culture. a WT cells show characteristic sporulation development including clostridial-form bulging cell shape. b–c M150B and ΔSpo0A and cells are rod shaped with no obvious sporulation development. d Isolation and enlargement of individual WT cell image from 7A shows spore core (c), cortex (cx), granulose bodies (g), and the multilayered spore coat structure (solid red arrow). e, f Isolation and enlargement of individual M150B and ΔSpo0A cell images from 7b, c show probable mesosomes (thick striped arrows) and globular electron dense regions (fine striped arrows)