A “Virtual” Bacterial Unknown Identification A “Virtual” Bacterial Unknown Identification Family Enterobacteriaceae Phylum Gammaproteobacteria Gram-negative Enteric bacteria Genera Escherichia...

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A “Virtual” Bacterial Unknown Identification A “Virtual” Bacterial Unknown Identification Family Enterobacteriaceae Phylum Gammaproteobacteria Gram-negative Enteric bacteria Genera Escherichia Salmonella Shigella Yersinia Edwardiella Klebsiella Proteus Morganella Providencia Enterobacter Hafnia Citrobacter In the following pages, you will see your own organism’s test results. Usually, a picture of the uninoculated medium will be alongside. You have to record whether your bacterium is + or – for the test result. Be sure to read over the appropriate exercise in the lab manual first before interpretation of your test result. The exercise also gives you the purpose of the test, how it is inoculated, how it is read, what indicator or reagent is used, and so on. Pages 15-17 are tables of biochemical tests for the major genera of the family of Enterobacteriaceae. Your unknown is one of those listed. You will use the tables to help you identify the bacterium. The unknown report to turn in This exercise is worth 50 points The identification sheet with all test results for YOUR organism, including the genus and species name for it—see LAST page of PP Is your organism a strict aerobe, strict anaerobe, or facultative? An explanation of how you chose that particular genus—what key tests For your particular genus and species of bacterium What kinds of infections are caused? What is the normal habitat (human, all animals, soil, air, etc.)? Questions on page 7—for each biochemical test You are doing it individually Plate culture and staining This is a gram stain: What is the gram reaction? The morphology? Acidfast stain done: negative Endospore stain done: no spores Flagella stain: peritrichous Isolation plate culture Any pigment? Describe the colonies (using the exercise in your lab manual called “Colony Morphology” Oxygen Requirement Look at the exercise on O2 requirements in your lab manual. Will you call your microbe---strict aerobe, strict anaerobe, or facultative anaerobe? Thioglycollate brothTSA plates in 3 oxygen environments Your organism on 3 different TSA plates in 3 different environments uninoculated after incubation Biochemical tests In your group’s write up of the lab report, you will have to answer these questions: What is the purpose of the test? What is the medium used for that test? What indicator is in the medium (so it can be interpreted) OR what reagent is added (after the organism is grown in/on the medium) to see the test reaction? What does a + reaction look like? What does a – reaction look like? What reaction does your organism have? Inoculation & interpretation of tests on day 1 Catalase test Oxidase test TTC agar deep uninoculated YOUR ORGANISM’S TEST RESULTS after incubation Biochemical test results – IMViC tests Indole test (SIM) H2S test Citrate test MRVP tests Methyl red Voges-Proskauer/VP uninoculated uninoculated uninoculated YOUR ORGANISM’S TEST RESULTS after incubation, with reagent after incubation after incubation, with reagent after incubation, with reagent Biochemical test results Nitrate test (NO3 reduction) at left Urea hydrolysis test middle O-F glucose at right (oxidation or fermentation) uninoculated uninoculated uninoculated YOUR ORGANISM’S TEST RESULTS after incubation after incubation after incubation, with reagents Biochemical test results Carbohydrate broths Glucose Lactose Sucrose Mannitol Gelatin agar deep (hydrolysis) uninoculated uninoculated YOUR ORGANISM’S TEST RESULTS after incubation after incubation Biochemical test results Decarboxylase broths Arginine Lysine Ornithine Deaminase (phenylalanine) uninoculated uninoculated YOUR ORGANISM’S TEST RESULTS after incubation, all 3 amino acid broths look the same after incubation, with reagent Biochemical test results Casein Starch Lipid uninoculated uninoculated YOUR ORGANISM’S TEST RESULTS after incubation, with reagent after incubation after incubation uninoculated ONPG (Beta galactosidase) DNAse Biochemical test results YOUR ORGANISM’S TEST RESULTS uninoculated uninoculated after incubation after incubation Family of Enterobacteriaceae Bergey’s Manual of Bacterial Identification Biochemical chart for unknown identification (+) or (-) = usual reaction, d = different reactions