RT Journal Article SR Electronic(1) A1 Mackey, B. M. A1 Morris, J. G.YR 1971 T1 Ultrastructural Changes during Sporulation of Clostridium pasteurianum JF Microbiology, VO 66 IS 1 SP 1 OP 13 DO https://doi.org/10.1099/00221287-66-1-1 PB Microbiology Society, SN 1465-2080, AB SUMMARY: Rapid sporulation of a strain of Clostridium pasteurianum has been achieved in anaerobic batch culture, using a simple, defined medium containing only salts, glucose, l-cysteine and ammonium ions. Electron microscopy revealed that spore coat production preceded formation of spore cortex; both spore coat and exosporium were multilamellar structures, and the exosporium appeared to possess a central, basal pore. The production of a refractile spore from a vegetative cell took about 9 to 10 h. at 35° from septation to engulfment of the forespore took 1.9 h.; spore coat material appeared 2.9 h. after engulfment, and spore cortex deposition commenced after a further 2.6 h. Approximately 80 % of the organisms produced mature, refractile spores. The various developmental stages occurred sufficiently synchronously to render the system amenable to future, correlative biochemical investigation., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-66-1-1