Effect of Lysozyme on Resting Spores of Bacillus Megaterium

Abstract

Resting spores of Bacillus megaterium ATCC 9885 were found to be markedly affected by lysozyme. Exposure to as little as 1.5 Ag of lysozyme per ml caused the spores to lose refractility, the darkened spores to shed their coat structures, and the spore central bodies to lyse. The spores of seven other strains of B. megaterium and seven other Bacillus species were not similarly affected by lysozyme. Proteolytic enzymes such as pronase, trypsin, pepsin, and subtilisin did not induce the change. The action of lysozyme differed in certain important respects from that of common "physiological" germinants. Its action was considered to be direct via its enzymatic attack on exposed sites directly accessible in the resting spores of B. megaterium ATCC 9885.

Germination of Heat- and Alkali-Altered Spores of Clostridium perfringens Type A by Lysozyme and an Initiation Protein

“…The results on lysozyme-initiated germination are similar to those reported for B. megaterium ATCC 9885 (14), in which lysozyme (1.5 yg/ml) caused germination-like changes in untreated resting spores. In the present experiments, slight germination of heat-shocked spores was obtained after 48 hr with a lysozyme concentration as low as 0.02 ,ug/ml.…”

“…Lysozyme-induced germination of the heatinjured spores was greatest at about 60 C (Fig. 7), which is in contrast to the results reported for B. megaterium ATCC 9885 spores where lysozyme-induced germination was not affected by a temperature as high at 70 C or a pH as low as 5.0 (14).…”

“…B. megaterium ATCC 9855 has been shown to be sensitive to lysozyme without pretreatment with bond-breaking reagents (14). Presumably, the mucopeptide was directly accessible to lysozyme, perhaps owing to a defective spore coat.…”

Dehydration partitioned within core protoplast accounts for heat resistance of bacterial spores

“…Spores of strain ATCC9885 (Fig. 1B) were seen always to be lacking an exosporium and frequently to have defects in the coat-outer membrane complex, so that the cortex of this spore also is accessible to lysozyme [4].…”

(Symposium on Bacterial Spores : Paper IV). Germination and the Problem of Dormancy

“…Egg white lysozyme will directly cause germination of spores of B. megaterium ATCC 9885 (Suzuki & Rode, 1969), but more generally it only initiates germination of spores which have been pretreated to sensitize them. The usual sensitization procedure involves incubating spores in urea (8 M)+p-mercaptoethanol (10% w /~) a t pH 2.8 for 1 h at 37", followed by washing, suspension in NaOH (0.1 N) for 15 min at 4" and washing again (Gould & King, 1969).…”