Bacillus everyone should have bacillus by now check

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Bacillus Everyone should have Bacillus by now. Check your Plates for the characteristic Matte Appearance of Bacillus Colonies. Make a Smear from an isolated Colony, confirm that the Bacteria in this Colony are Gram Positive Rods. If you want -- and it would be Good Practice -- make a Spore stain of your Bacillus Isolate. Skin Bacteria Everyone should have Micrococcus luteus (Yellow Colonies that are not surrounded by any Zone of Clearing) or Staphylococcus epidermidis (White Colonies that are surrounded by a Zone of Clearing). Make a Smear from an isolated Colony and confirm that the Bacteria in this Colony are Gram Positive Cocci. Use this same Colony to streak a YGC Plate. Enteric Bacteria And everyone probably has E. coli (from the Fly-Butt Green Colonies on your EMB Plate) or Enterobacter aerogenes (from the Hot Pink Colonies on your EMB Plate). Pick an isolated Colony, make a Smear, and check if the Bacteria in this Colony are Gram Negative Rods. Use this same Colony to inoculate an IMViC Set-up (which consists of a Tube of Tryptone Broth [for the Indole Test], a Tube of MR-VP Broth [for the Methyl Red and Voges Proskauer Test] and a Citrate Slant [for the Citrate Test]).
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Lab 6 Page 23 Biochemical Identification of Isolates You may have noticed that one Gram Negative Rod (say, E. coli ) looks pretty much like any other Gram Negative Rod (say, Enterobacter ) under the Microscope. True, there are differences in Colony Size and Morphology, but we need some better way to distinguish different Bacteria. Bacteria are uniquely metabolically diverse Organisms. Different Species of Bacteria -- which may very well look Identical on a Petri Plate or under the Microscope -- can have very different (and sometimes Distinctive) Metabolic Pathways. So we can distinguish different Bacteria by asking a Series of Biochemical Questions. The first -- and most Important -- Question is “Are you a Gram Positive Bacterium or are you a Gram Negative Bacterium?” If the Answer is “Gram Positive” then under our (very limited) Identification Scheme you’ll know you have one of the following Bacteria: • Bacillus cereus • Micrococcus luteus • Staphylococcus epidermidis • Streptococcus lactis If the Answer if “Gram Negative” then you’ll know you have one of these Bacteria: • Enterobacter aerogenes • E. coli • Pseudomonas putida Then we’ll be asking what these Bacteria like to eat and what they produce as By- Products. We have one Set of Questions for Gram Positive Bacteria and another Set of Questions for Gram Negative Bacteria. There are certain Tests that are performed on Gram Positive Bacteria (Catalase and YGC). There are certain Tests that are performed on Gram Negative Bacteria (Oxidase and IMViC). Asking the Oxidase Reaction of a Gram Positive Bacterium is the equivalent of asking who plays Quarterback for the San Francisco Giants.
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