Purified superdormant spores of Bacillus cereus, B. megaterium, and B. subtilis isolated after optimal heat activation of dormant spores and subsequent germination with inosine, d-glucose, or l-valine, respectively, germinate very poorly with the original germinants used to remove dormant spores from spore populations, thus allowing isolation of the superdormant spores, and even with alternate ...

To investigate the primary structural determinants affecting heat resistance of Clostridium sporogenes spores, electron micrographs of heat-sensitive (D121 degrees C = 0.56 min) and heat-resistant (D121 degrees C = 0.93 min) spores of C. sporogenes were taken with a transmission electron microscope. The mean thickness (+/- standard deviation [SD]) of coat layers and cortex regions of heat-sensi...

The study compares the course of spore season Alternaria in Bialystok, Cracow, Olsztyn, Piotrkow Trybunalski, Sosnowiec, Szczecin, Warsaw, and Wroclaw 2020. investigations were conducted using volumetric method. was defined as period which 90% annual total catch occurred. started first Bialystok on May 19 lasted June 28 Wroclaw. highest airborne concentration 1052 spores/m3 noted July 30. sum s...

fungal conidia and spores are among various organisms found in the air, causing different types of mycoses. in this study (from february 1994 until march 1995) fungal spores and conidia were collected by their settlement on to petri - dishes from 33 locations in babol city during 4 seasons. plates of sabouraud dextrose agar were laid 1.5 m. from the ground and then sent to mycology laboratory w...

Heat shock of dormant spores of Bacillus stearothermophilus ATCC 7953 at 100 or 80 degrees C for short times, the so-called activation or breaking of dormancy, was investigated by separating the resulting spores by buoyant density centrifugation into a band at 1.240 g/ml that was distinct from another band at 1.340 g/ml, the same density as the original spores. The proportion of spores at 1.240...

The effects of highly toxic and nontoxic spores of Stachybotrys atra were investigated in mice after six intranasal administrations of 1 x 10(5) and 1 x 10(3) spores in phosphate-buffered saline during a 3-week period. Toxic spores contained the trichothecene mycotoxins, satratoxins G and H, as well as the immunosuppressant stachybotrylactones and -lactams. No trichothecenes were detected in th...

During germination of spores of Bacillus species the degradation of the spore's pool of small, acid-soluble proteins (SASP) is initiated by a protease termed GPR, the product of the gpr gene. Bacillus megaterium and B. subtilis mutants with an inactivated gpr gene grew, sporulated, and triggered spore germination as did gpr+ strains. However, SASP degradation was very slow during germination of...

Sporulation of Clostridium botulinum 113B in a complex medium supplemented with certain transition metals (Fe, Mn, Cu, or Zn) at 0.01 to 1.0 mM gave spores that were increased two to sevenfold in their contents of the added metals. The contents of calcium, magnesium, and other metals in the purified spores were relatively unchanged. Inclusion of sodium citrate (3 g/liter) in the medium enhanced...