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These two traits the ability to produce heat

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These two Traits -- the Ability to produce Heat-Resistant Spores and the Ability to grow Aerobically -- provide the Basis of our Bacillus Selection Strategy. A Soil Sample will be suspended in Water and Pasteurized to kill all Vegetative Bacteria. This Pasteurized Suspension -- containing only Spores -- is streaked onto a Nutrient Agar Plate, which will then be incubated Aerobically. Bacillus Spores and the Clostridium Spores will both germinate but only the Vegetative Cells of Bacillus will be able to grow under these Conditions. 1. Direct Isolation/ 2. Selection A small Amount of Soil will be inoculated into about 5 ml of Water and the resultant Suspension will be vortexed and Pasteurized at 80°C for 20 Minutes. After Pasteurization, the Soil Suspension will be cooled to Room Temperature and vortexed again. You’ll then use your Loop to streak a Loopful of this Pasteurized Soil Suspension onto a Nutrient Agar Plate, which will be incubated at 30°C for 48 Hours. This Plate should produce large Numbers of Bacillus Colonies with a Characteristic “Frosted Glass” Appearance. (If you get a swirling Pattern of Growth on this Plate, it means you’ve isolated the dreaded Bacillus mycoides , which seems to be able to get into absolutely Everything. We’ll get rid of any such Plates.) A Gram Stain of Bacteria from an Isolated Colony should reveal Gram Positive Rods (and possibly Clear Spores). A Spore Stain of Bacteria from an Isolated Colony should reveal the Presence of Endospores (Spores).
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Lab 1 Page 27 3. Purification An Isolated Colony displaying Characteristic Morphology on a Nutrient Agar Plate will be used to streak a new Nutrient Agar Plate, which will be incubated at 30°C for 48 Hours. This new Plate should produce large Numbers of Bacillus Colonies with the Characteristic “Frosted Glass” Appearance. A Gram Stain of Bacteria from an Isolated Colony should reveal Gram Positive Rods. A Spore Stain of Bacteria from an Isolated Colony should reveal the Presence of Spores. 4. Identification A Spore Stain of Bacteria from an Isolated Colony showing the Presence of Spores is considered Confirmation that the Isolate is Bacillus . Biohazard Note You are performing an Isolation of an unknown Strain of Bacillus . The Strains of Bacillus you will isolate are almost certainly Benign, but they should be handled as if they are Pathogenic. __________________________________________________ “I sense something; a presence I've not felt since... He is here.” ‘Obi-Wan Kenobi? What makes you think so?’ “A tremor in the Force. The last time I felt it was in the presence of my old master.” ‘Surely he must be dead by now.’ “Don't underestimate the Force.” ‘The Jedi are extinct, their fire has gone out of the universe. You, my friend, are all that's left of their religion. Yes?’ We have an emergency alert in detention block AA-23.
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