Sporulation efficiency and spore quality in a human intestinal isolate of Bacillus cereus

Probiotics as an Alternative to Antibiotics: Genomic and Physiological Characterization of Aerobic Spore Formers from the Human Intestine

“…Cells of all thirty-two strains showed a rod-shaped morphology under the light microscope and were able to form phase-bright ellipsoidal endospores localized in central or sub-terminal positions. Only strain MV19 formed unusual spores that have been described elsewhere [ 41 ]. In addition to spores, strains MV19 [ 41 ], MV21, MV26, and MV30 formed multiple parasporal granules (possibly inclusion bodies) ( Supplementary Materials Figure S1 ).…”

“…Biofilm formation was tested as previously reported [ 41 ]. Briefly, growing cells were inoculated into 24-well culture plates with three different media: LB, DSM [ 42 ], and S7 minimal medium (for 1 L: 50 mM morpholine-propane-sulfonic acid (MOPS) (adjusted to pH 7.0 with KOH), 10 mM (NH 4 ) 2 SO 4 , 5 mM potassium phosphate (pH 7.0), 2 mM MgCl 2 , 0.9 mM CaCl 2 , 50 μM MnCl 2 , 5 μM FeCl 3 , 10 μM ZnCl 2 , 2 μM thiamine hydrochloride, 20 mM sodium glutamate, 1% glucose, 0.1 mg/mL phenylalanine, and 0.1 mg/mL tryptophan) [ 43 ].…”

“…Briefly, growing cells were inoculated into 24-well culture plates with three different media: LB, DSM [ 42 ], and S7 minimal medium (for 1 L: 50 mM morpholine-propane-sulfonic acid (MOPS) (adjusted to pH 7.0 with KOH), 10 mM (NH 4 ) 2 SO 4 , 5 mM potassium phosphate (pH 7.0), 2 mM MgCl 2 , 0.9 mM CaCl 2 , 50 μM MnCl 2 , 5 μM FeCl 3 , 10 μM ZnCl 2 , 2 μM thiamine hydrochloride, 20 mM sodium glutamate, 1% glucose, 0.1 mg/mL phenylalanine, and 0.1 mg/mL tryptophan) [ 43 ]. The plates were incubated for 48 h at 37 °C, and then biofilm production was assessed by crystal violet assay as previously described in [ 41 ]. The experiment was performed in triplicate.…”

Bacterial Spore-Based Delivery System: 20 Years of a Versatile Approach for Innovative Vaccines

“…Spores of Bacillus megaterium or in Bacillus cereus and its close relatives Bacillus anthracis and Bacillus thuringensis are surrounded by a further layer, the exosporium [56,57]. A basal layer of glycoproteins forms this structure with hair-like protrusions [32].…”

“…In the genomes of Clostridium spp., the B. subtilis coat genes are even less conserved [56]. Despite the spore surface's physical-chemical properties and structure varying from specie to species, the coat of the bacterial spores, by itself or in combination with the exosporium, plays a crucial role in spore protection and the initiation of germination [53,57].…”