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156 Cards in this Set
- Front
- Back
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Starch is broken down (starch hydrolysis) by the enzyme ______, yielding a final end product of _______ used for energy synthesis.
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amylase
glucose |
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The reagent added to the plate to visualize a positive reaction was _______.
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iodine
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What denotes a POSITIVE reaction for Starch Hydrolysis?
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A clearing of the media around the bacterial growth.
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For Lipid Hydrolysis, what are the final end products? (2)
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1. fatty acids
2. glycerol |
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For Casein Hydrolysis, the substrate is ______ (found in milk) which is proteolytically cleaved by either p________ or c_______ into the final end product of ________.
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casein - proteases - caseases - peptone
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The process causing cleavage is called _______.
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Hydrolysis
Cleavage = The splitting of a complex molecule, such as a polysaccharide, into simpler molecules. |
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For Gelatin Hydrolysis, what is the substrate and what is it degraded by?
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substrate = gelatin
degraded by gelatinase |
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For Gelatin Hydrolysis what are the final end products?
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amino acids
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What denotes a POSITIVE test result for Gelatin Hydrolysis?
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Positive: media becomes liquid at room temperature
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What are the 4 tests we performed for Hydrolysis?
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Starch, Lipid, Casein and Gelatin
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What 3 tests were performed for Gram-POSITIVE tests?
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1. Catalase Test
2. Staphylococcus Identification 3. Streptococcal Identification |
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Which Gram-POSITIVE coccus bacterium is positive for Catalase?
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Staphylococcus
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Which Gram-POSITIVE coccus bacterium is negative for Catalase?
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Streptococcus
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Know procedure for Catalase test.
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Procedure:
1. Drop 2 small drops of 3% hydrogen peroxide onto a clean glass slide. Using a sterile loop, put a loopful of the Staph organism into one of the drops. Observe for a bubbling reaction. 2. Repeat for Strep |
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Know how to read MSA
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Both organisms growing on the plate above are halotolerant. The organism (Staphylococcus aureus) indicated by the orange arrow is capable of mannitol fermentation, signified by the color change in the surrounding media. The organism (Staphylococcus epidermidis) indicated by the blue arrow is not capable of mannitol fermentation.
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Mannitol Salt Agar is selective for _______ species, differentiates ___________ ____ from other species.
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Selects: Staphylococcus
Differentiates: Staphylococcus aureus |
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Mannitol Salt Agar contains ____% NaCl which makes it intolerant for other bacteria.
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7.5%
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Mannitol Salt Agar, what is the substrate? What is the pH indicator?
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Mannitol
phenol red |
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Mannitol Salt Agar, what causes the yellowing of the media?
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Yellowing is caused by fermentation of mannitol by S. aureus.
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Which Staph species will give a positive DNase?
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Staphylococcus aureus
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Read the results for Staphylococcus Identification.
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The organism on this plate is positive for mannitol fermentation, positive for DNase production, and susceptible to the antibiotic Novobiocin.
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What is the color indicator for DNase agar test?
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Methyl green
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For Staph identification, which agar was used to test Novobiocin sensitivity?
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Mueller-Hinton agar
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For Mueller-Hinton, the test is either scored with either an R (resistant) or S (sensitive) and you are looking at what to determine R or S?
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Zone of inhibition around the Novobiocin disk
18 mm or greater = S 18 mm or less = R |
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What determines an S for Novobiocin test?
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18 mm or greater
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Know how to read Blood Agar plates.
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You are to look for hemolytic activity.
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Blood Agar plate: ____ is partial destruction of red blood cells. ____ is complete destruction of RBCs and ______ is no destruction of RBCs.
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alpha, beta, gamma
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Blood agar test was used to identify __________ bacteria.
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Streptococcus
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The _____ agar was used to test SXT antibiotic sensitivity.
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Blood
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On Blood Agar, what denotes whether the organism is R or S?
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S = 20 mm or greater
R = 20 mm or less |
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On Blood Agar, what denotes whether the organism is R or S?
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S = ANY zone of inhibition
R = NO zone of inhibition |
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What is the substrate for Bile Esculin?
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Esculin
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RE Bile Esculin, the substrate (esculin) is hydrolyzed to produce end products which read with the color indicator to produce the black color. How much must be black before a positive result can be made?
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The black precipitate must be in >50% of the tube to be considered positive.
The esculetin reacts with ferric ammonium citrate to form a blackish precipitate. |
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RE MSA growth - what is the only STREP species to grown on MSA?
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Enterococcus faecalis
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Know that Triple Sugar Iron (TSI) test is for Gram-negative testing. How are results read?
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Carbohydrate fermentation: TSI slants contain three carbohydrates: glucose (0.1%), sucrose (1%), and lactose (1.0%), as well as phenol red (pH indicator) and peptones. Fermentation of the carbohydrates into acid end-products will result in a yellow color on the slant and/or butt as the acids react with the phenol red. Note that all organisms will preferentially ferment glucose before fermenting lactose and/or sucrose. Results in the slant and butt are reported as "A" for acid, (indicated by a yellow color) and "Alk" for alkaline (indicated by a red or orange color).
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What are the procedures for TSI inoculation?
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1. Obtain a TSI slant and label it with your name and the name of your organism.
2. Using a sterile loop, inoculate the slant of the tube using a zig-zag streak. Then use a sterile needle to stab the butt of the tube 5-10 times to push the organism down into the butt. 3. Make sure the cap is loose but secure. Incubate overnight @ 37 degrees C. |
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On the Catalase Test, what causes the bubbles for the Staph?
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The bubbles are the molecule oxygen that is produced as the catalase breaks down the hydrogen peroxide.
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What is the procedure for inoculating MSA media?
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1. Inoculate MSA with your organism using a STRAIGHT-LINE STREAK.
2. (For Strep, place in Anaeropak box) and incubate @ 37 degrees C for 48 hours. 3. Be sure to label your plate with your name and name of organism. |
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What is the procedure for DNase inoculation?
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1. Inoculate (use loop) MSA with your organism using a STRAIGHT-LINE STREAK.
2. Iincubate @ 37 degrees C for 48 hours. 3. Be sure to label your plate with your name and name of organism. |
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What is the procedure for the Novobiocin sensitivity test?
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1. Create a liquid suspension of Staph species by diluting 2-3 loopfuls of the organism into a saline tube using a sterile loop.
2. Using a sterile swab, completely cover the Mueller-Hinton plate with the suspension to create a bacterial lawn. 3. Place and seat a Novobiocin disc in the center with sterile forceps. 4. Incubate @ 37 degrees C for 48 hours. |
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What is the procedure for Blood Agar Strep test?
(Used for Streptococcus identification) |
1. Label plates (Name and Organism).
2. Suspend several loopfuls of the organism into a 0.85% SALINE TUBE. Should be slightly-moderately turbid. Using a sterile swab, dip into the inoculated saline and completely swab 3/4 of the Blood Agar plate, creating a lawn. 2. On the other 1/4 of the plate, do a straight line streak with a sterile loop to see the hemolysis pattern. 3. Place and seat a Bacitracin disc and an SXT (trimethoprim-sulfamethoxazole) disc equidistant within the designated area on the swabbed area of the blood plate. 4. Place Blood Agar plate in an Anaeropak box at 37 degrees C for 48 hours. |
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How should the Blood Agar plate be inoculated with Strep?
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What is the procedure for the Bile Esculin slant?
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1. With a loop, streak a Bile Esculin slant tube with your Streptococcus (or Enterococcus)
organism using a zig-zag motion. Make sure to replace the cap so that it is loose, but secure. 2. Place the blood agar plate and Mannitol salt agar plate into an Anaeropak box (for an aerobic environment enriched with carbon dioxide). Incubate at 37 oC for 48 hours. 3. Incubate the Bile Esculin slant tube at 37 oC for 48 hours. |
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What is the pH indicator for the Triple Sugar Iron Test?
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Phenol red is used for determining if carbohydrates were fermented in testing Gram-negatives.
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What is the color indicator for the TSI?
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The color indicator for H2S production is FERROUS SULFATE.
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What is the TSI substrate for the H2S production?
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Sodium thiosulfate
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What is the TSI substrate for carbohydrate fermentation?
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Any of the carbohydrates: (glucose (0.1%), sucrose (1%), and lactose (1.0%), or the peptones.
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The TSI agar slants are used to differentiate between gram-? ____.
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Gram-negative bacilli.
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What is the procedure for the Urease Test?
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PROCEDURE:
1. Obtain a urea broth tube and label the tube with your name and the name of your microorganism. 2. Using a sterile loop, inoculate your tube. 3. Make sure the cap is loose but secure and incubate at 37 °C. |
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What is the substrate for the Urease test?
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Urea is the substrate in the broth.
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What is the enzyme for the Urease test?
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The enzyme (from the bacterium) is UREASE.
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Urease is _______ so when water is introduced, the enzyme breaks the c______-n_______ bond and creates 3 end products: ____, ____ and ____.
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Hydrolytic
Carbon-nitrogen WAC: water, ammonia and carbon dioxide. |
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RE Urease test, the ammonia _____ the pH, which reacts with the pH indicator ________ in the broth, changing the broth to a ____ ______ color.
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increases, phenol red, hot pink
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What is the procedure for the SIM media?
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PROCEDURE:
1. Obtain a SIM deep tube and label the tube with your name and the name of your microorganism. 2. Inoculate SIM deep tube with a straightened sterile needle, stabbing the butt all the way to the bottom a single time. 3. Make sure the cap is loose but secure and incubate at 37 °C. |
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What 3 things does the SIM test for?
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SIM agar deep tubes test for three things: (1) indole production, (2)
hydrogen sulfide production, and (3) motility. |
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What does the SIM deep contain for indole production?
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Substrate: Tryptophan
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What does the SIM deep contain for H2S production?
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Substrate: Sodium Thiosulfate
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Does the SIM contain peptones?
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Yes
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What is the H2S indicator for SIM?
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Ferrous sulfate
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What are the 3 end products that the enzyme Tryptophanase (supplied by bacteria) can degrade the tryptophan to?
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indole, pyruvate and ammonia
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Kovac's reagent is ADDED to the media. What does it contain?
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HCl, butanol, para-dimethyl-amino-benzaldehyde.
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Kovac's reagent is ADDED to the media. What is the color result for indole production?
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A cherry red color
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On the SIM, if a black coloration occurs, the bacteria has produced which enzyme?
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Thiosulfate reductase (A & B are positive for H2S production.)
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On the SIM, if bacteria produced the thiosulfate reductase enzyme, what will happen?
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The enzyme, thiosulfate reductase will reduce the sulfur in the sodium thiosulfate to H2S.
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RE SIM, when H2S is produced, the gas reacts with the ______ ______ and will change the media to a _____ color.
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Ferrous sulfate, black
This is POSITIVE for H2S production. |
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What are the procedures for the MR portion of the MR-VP test?
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PROCEDURE:
1. Obtain an MRVP broth tube and label the tube with your name and the name of your microorganism. 2. Inoculate the MRVP broth tube with a sterile loop. 3. Make sure the cap is loose but secure and incubate at 37 °C. RESULTS: 1. Retrieve your MRVP broth tube inoculated during the previous lab period. 2. Transfer 1 ml of your MRVP broth to an empty tube. Add 10 drops of methyl red color indicator. Mix well and observe for a continuing red color, which indicates a positive result for the methyl red test. A positive MR result means that the organism has fermented glucose to produce a mixture of fermentation acids that were able to lower the pH below 4.4. |
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The VP test is performed after the MR test. What is the VP procedure?
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Transfer another 1 ml of your MRVP broth to an empty tube. Add 12* drops of
Barritt’s Reagent A, but do not mix. Then add 5* drops of Barritt’s Reagent B to the same tube, and mix thoroughly. Incubate at room temperature for a minimum of 25 minutes to allow the reaction to occur. If a dark red band begins to appear at the top of the liquid, this indicates a positive result for the Vogues-Proskauer test. A positive VP results means that the organism has fermented glucose to produce acetic acid only, which has been converted to acetylmethylcarbinol. (*Your instructor will tell you how many drops to add.) |
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What does MR-VP stand for?
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Methyl Red - Vogues Proskauer
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What does the MR-VP broth contain?
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Peptones (for protein), glucose (substrate) and a phosphate buffer.
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Know how to read the results of the SIM test.
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Know how to read the results for the MR-VP test.
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Know how to read the test results for the Urease Test.
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Know how to interpret the results for the TSI tests.
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The Methyl Red Test is designed to detect bacteria that will produce ______ acids and overcome what?
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multiple
overcomes the phosphate buffer |
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What are examples of the multiple acids the MR could detect?
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Lactic acid, Formic acid and Acetic acid
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How is a positive test indicated for MR test after adding the Methyl Red reagent?
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Red coloring
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The VP test is designed to test bacteria that will produce only ONE acid that the phosphate buffer will be able to NEUTRALIZE by converting it to what?
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AMC or acetylmethylcarbinol
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What is one example of an acid that the phosphate buffer can neutralize by converting it to acetylmethylcarbinol?
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Acetic acid
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Positive VP Test is indicated after addition of what to the inoculated tube?
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Barritt's Reagent A and Barritt's Reagent B which, when positive, will produce a maroon band at top of broth.
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What is in Barritt's Reagent A and Barritt's Reagent B?
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Barritt's Reagent A = alpha-naphthol
Barritt's Reagent B = 40% KOH After adding reagents, must incubate 20 minutes at room temperature before reading. |
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What 4 things does the Citrate Agar contain?
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Sodium citrate (substrate), brom thymol blue (pH indicator), sodium and water.
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Will fermentation occur in the Citrate Agar?
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NO because NO carbohydrates in the media.
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What two INTERMEDIATE PRODUCTS will citrase break down sodium citrate into?
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The INTERMEDIATE PRODUCTS are Oxaloacetic acid and Acetic Acid.
Oxaloacetic acid's END PRODUCT = pyruvate Acetic acid's END PRODUCT is Carbon dioxide. |
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What cause the Prussian Blue positive reaction of the Citrate Utilization Test?
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The end product of Acetic acid reacts with sodium and water (already present) to form sodium carbonate (alkaline) changing pH of media which reacts with brom thymol blue pH indicator.
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What does the Nitrate Reduction Test contain?
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Nitrate (substrate), peptones and beef extract
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What are the reagents added to Nitrate Reduction Test AFTER INCUBATION?
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Nitrate Reagent A and Nitrate Reagent B
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What do Nitrate Reagent A and Nitrate Reagent B contain?
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Nitrate Reagent A = sulfanilic acid
Nitrate Reagent B = alpha-naphthylamine |
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What indicates a positive result for the Nitrate Reduction Test after adding Nitrate Reagent A and Nitrate Reagent B?
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Initially, a red color = positive.
After adding zinc, NO COLOR = positive |
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What causes the color changes for the Nitrate Reduction Test?
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If organism produces the enzyme, Nitrate Reductase, the nitrate will be reduced to nitrites.
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What causes NO color change after adding zinc for the Nitrate Reduction Test?
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NO COLOR = positive for DENITRIFICATION which means the bacteria have reduced the nitrate beyond nitrite to either ammonia or molecular nitrogen (N2)
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What are the 3 possible end products for the Nitrate Reduction Test?
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1. ammonia
2. nitrite 3. molecular nitrogen (N2) |
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Nitrate Reductase only reduces nitrates to what?
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Nitrites - however, DENITRIFICATION reduces nitrates to ammonia or molecular nitrogen (N2).
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What is the procedure for performing the Citrate Utilization Test?
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1. Inoculate the citrate agar with organism by streaking the surface of the slant with a sterile loop in a zig-zag motion. DO NOT STAB BUTT!
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What should you observe your Citrate Agar for?
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For color and bacterial growth. It is called the Citrate Utilization Test.
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What are the procedures for the Nitrate Reduction Test?
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1. Using a sterile loop, inoculate the nitrate broth.
2. Analyze your nitrate broth tube to determine if nitrate reduction has occurred: a. Add 12 drops of Nitrate Reagent A to the broth tube and mix thoroughly. Next, add 1 drop of Nitrate Reagent B and mix. If a red color is produced, this indicates a positive result for nitrate reduction. This means the organism has reduced the nitrate to nitrite. b. If no red color is produced, add a pinch of Zinc and mix thoroughly. Allow to sit for several minutes. If the broth turns red, this indicates that the zinc has reduced the nitrates and the organism is negative for nitrate reduction. c. If the addition of zinc does NOT cause a color reaction, the test is positive. This means that the organism has reduced the nitrate to nitrites and then reduced the nitrites to ammonia or molecular nitrogen. |
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Are reagents added to Triple Sugar Iron agar, Citrate slant, Urease broth or Lysine Iron agar?
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No
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What tests are reagents added to?
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Nitrate Reduction Test, Methyl Red - Vogues Proskauer and SIM deep.
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What is the procedure for the Lysine Iron Agar (LIA)?
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PROCEDURE:
1. Obtain a LIA slant and label the tube with your name and the name of your microorganism. 2. Using a sterile loop, inoculate the slant of the tube using a zig-zag streak. Then, use a sterile needle to stab the butt of the tube 5-10 times to push the organism down into the butt of the tube. Do not stab into the slant, only into the butt! 3. Make sure the caps are loose but secure, and incubate at 37 °C. |
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How do you read the Lysine Iron Agar test?
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How do you read these LIA results?
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Slant – Red is positive reaction for Lysine Deamination (+)
Purple is negative reaction for Lysine Deamination (-) Butt – Purple is positive reaction for Lysine Decarboxylation (+) Yellow is negative reaction for Lysine Decarboxylation (-) |
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What does the LIA contain?
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Lysine, glucose (substrate), peptones, brom cresol purple (pH indicator) sodium thiosulfate (H2S substrate) and ferric ammonium citrate (H2S color indicator)
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RE LIA, where does decarboxylation occur?
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In the butt, anaerobic conditions; end product of decarboxylation is amine.
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RE LIA, where does deamination occur?
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In the slant, aerobic conditions; end product of deamination creates an enzyme that reacts with the ferric ammonium citrate to produce a molecule which gives the slant a red color = positive. (Purple = negative)
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Which LIA process can H2S be produced (which yields a black coloration)?
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Deaminiation
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RE: Water Microbiology
Presumptive test uses what types of broths? |
Phenol Red Lactose Broth with Durham tubes.
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RE: Water Microbiology
What was the substrate and pH indicator used in the presumptive test? |
Substrate = Lactose
pH indicator = Phenol Red |
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What is a POSITIVE result for the presumptive test for water microbiology?
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Production of gas in the Durham tube.
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Be able to read the results from the Presumptive Test and use the results to determine the MPN. (Most Probable Number)
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What is the purpose of the MPN Test?
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The MPN test is a statistics-based test which estimates the number of fecal coliforms in a water sample based on the degree of lactose fermentation by organisms in the sample. In this test, a series of tubes of phenol red lactose broth are inoculated with measured amounts of water to determine if the water contains any lactose-fermenting bacteria that produce gas
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What does the Salmonella-Shigella (SS) Agar contain?
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Lactose (substrate), bile salts, ferric citrate and Neutral Red (pH indicator).
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For the SS Agar what will give pink colonies and why?
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On the Salmonella-Shigella Agar, pink is from Escherichia because they are LACTOSE fermenters.
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On the SS Agar, what will produce colorless colonies with black dots and why?
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On the Salmonella-Shigella Agar, Salmonella is colorless with black dots because they are H2S producers. (Ferric Citrate)
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On the SS Agar, what will grow colorless colonies?
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Shigella are colorless colonies on the Salmonella-Shigella Agar.
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What is the Rapid Strep Test based on?
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Antigen-Antibody reactions
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What does the Rapid Strep Test detect?
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Group A Streptococcus antigens
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What do the two colored lines on the dipstick denote on the Rapid Strep Test?
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Two lines = positive for Group A Streptococcus (Streptococcus pyogenes)
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On the Rapid Strep Test, what does the one colored line denote?
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Negative but test is working correctly
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On the Rapid Strep Test, no lines showing means what?
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The test did not work correctly
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What is the Rapid STAPH Test based on?
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Based on Staphylococcus aureus producing COAGULASE and PROTEIN A antigens on surface.
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RE: Rapid STAPH Test
What converts fibrinogen in blood to fibrin in order to produce a clot (for hiding from immune system)? |
Coagulase
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RE: Rapid STAPH Test
What does the Protein A do? |
Protein A binds to Fe region of IgG molecules
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The STAPH kit contains ______ particles coated with ______ and ___.
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Latex particles coated with FIBRINOGEN and IgG.
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RE: Rapid STAPH Test
Positive tests should have ________ reactions. |
agglutination
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For Transformation, know what cells were used for transformation process.
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Transformation refers to the ability of a microorganism to take up free DNA from the environment, and incorporate that DNA into their genome. Cells that have the capacity to do this are referred to as competent cells. Some genera of bacteria are naturally competent, such as Streptococcus, Bacillus, Haemophilus, and Pseudomonas. Those genera which are not naturally competent can be manipulated in the laboratory to become artificially competent. Artificial competency is typically induced using chemicals such as calcium chloride to increase the permeability of the cells. The most commonly used artificially competent species is the genetic workhorse Escherichia coli, which is an indispensable asset to the fields of genetic engineering and biotechnology.
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For Transformation Test, know what antibiotic was used for selection.
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Ampicillin (LB-amp)
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Be able to explain what DNA was transformed and which genes were on that DNA.
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transform the plasmid pGREEN into chemically
competent E. coli cells. The selectable marker on the pGREEN plasmid is a beta-lactamase gene which confers resistance to the antibiotic ampicillin. |
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Recipient cells that are
successfully transformed with the pGREEN plasmid will be what? |
It will be ampicillin-resistant and will produce
the green fluorescent protein, giving them a green coloration which is visible under ambient light conditions, and will fluoresce under UV light. |
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Starch is broken down by the enzyme ______ , yielding a final end product of _______ , which is used for what?
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Amylase
Glucose Glucose is used for energy synthesis. |
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Amylase is an ___cellular enzyme used for identifying _______ species.
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Extracellular
Bacillus |
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What was the reagent added to the Starch Hydrolysis plate to visualize a positive reaction?
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Iodine
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For the Starch Hydrolysis plate, what results denoted a positive reaction?
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Clearing of the media around the bacterial growth.
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For Lipid Hydrolysis, the lipid substrate is _____, which is degraded by the enzyme _______.
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Tributyrin
Lipase |
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For Lipid Hydrolysis, the final end products are ____ acids and _____.
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Fatty acids
Glycerol |
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For Casein Hydrolysis, the substrate is ______ (found I milk), which is proteolytically cleaved by either _____ or _______ into the final end product of _______.
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Casein
Proteases or Caseases Peptones |
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The process causing the cleavage of casein to either proteases or Caseases is called what?
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Hydrolysis
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For Gelatin Hydrolysis, the substrate is _______ which is degraded by ___________.
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Gelatin
Gelatinase |
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What are the end products of Gelatin Hydrolysis?
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Amino acids (liquid = positive for Gelatin Hydrolysis)
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A positive test for Gelatin Hydrolysis is what?
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Agar becomes liquid at room temperature.
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Which Gram-positive coccus bacterium is positive for Catalase and which Gram-negative coccus is negative for Catalase?
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Staphylococcus species produce Catalase and are positive.
Streptococcus and Enterococcus species do not produce Catalase and are negative. |
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For Staphylococcus what was the antibiotic disk used on the Muellar-Hinton Agar?
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Novobiocin
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Mannitol Salt Agar is selective for _________ species and differentiates ____________ ____ from other species.
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Staphylococcus
Staphylococcus aureus |
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Mannitol Salt Agar contains ___% NaCl, _____ is the substrate and _____ ___ is the pH indicator.
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7% NaCl
Mannitol (substrate) Phenol red (pH indicator) |
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Yellowing of the Mannitol Salt Agar is caused by what?
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Fermentation of mannitol by Staphylococcus aureus.
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Which Staph species will give a positive DNase result on DNase Agar?
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Staphylococcus aureus species.
(Example: Staphylococcus xylosis is able to produce the hydrolytic enzyme called DNase.) DNase Detection DNase detection is an easy and useful test that can help greatly in the identification of various Staphylococcus species. Staphylococcal species other than Staphylococcus aureus that can produce DNase include:Staphylococcus caprae, Staphylococcus hyicus, Staphylococcus chromogens, Staphylococcus intermedius. |
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What is the color indicator for DNase test?
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Methyl green
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For Stahylococcus identification using the Novobiocin disk, how are results scored and what denotes these scores?
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R(resistant) = 18 mm or less field of inhibition
S (sensitive) = 18 mm or greater field of inhibition |
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Streptococcus identification: know procedure for inoculating Bile Esculin Agar.
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Using a sterile loop, streak the Bile Esculin slant tube with the organism. Cap loose and incubate 30 degrees C for 48 hours. Observe Bile Esculin tube for esculin hydrolysis (black precipitate throughout agar).
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Streptococcus identification: know procedure for inoculating Muellar-Hinton. What are the 2 antibiotic disks used?
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SXT and Bacitracin
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On Blood Agar, looking for ______ activity.
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hemolytic
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On Blood Agar, ____ is partial destruction of red blood cells. _____ is complete destruction of RBCs. _______ is no destruction of RBCs.
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Alpha
Beta Gamma |
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In identifying Strept species with SXT antibiotic disks, how much zone of inhibition is needed for each score (Susceptible and Resistant)?
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Greater than 20 mm = S (susceptible). Less than 20 mm = resistant.
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In identifying Strept species with Bacitracin antibiotic disks, how much zone of inhibition is needed for each score?
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ANY zone of inhibition= S (susceptible).
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Bile Esculin Agar, what is the substrate?
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Esculin
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Know how to read the Nitrate Reduction Test.
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What is the procedure for inoculation of Muellar-Hinton Agar?
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Create a liquid suspension of your Staphylococcus species by diluting 2-3 loopfuls of the
organism into a saline tube using a sterile loop. Using a sterile swab, completely cover the Mueller-Hinton portion of the plate with the suspension to create a bacterial lawn. Place and seat a Novobiocin disc in the center with sterile forceps. Incubate plate at 37 degrees C for 48 hours. |
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Know how to read the Tri-Plate.
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