C gram negative pseudomonas positive for oxidase

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c. Gram-negative pseudomonas: positive for oxidase activity. Color present. 2. Catalase test: a. Gram-positive staph aureus: catalase activity positive. Bubbles present. b. Gram-positive streptococcus: no catalase activity. No bubbles. 3. Coagulase test: a. Negative control: no coagulation
b. Gram-positive staph epidermidis: no coagulation c. Gram-positive staph aureus: coagulated TK07 Secondary Assays for Bacterial Characterization Objective: To profile bacterial populations based on additional biochemical approaches to better determine growth / metabolic characteristics. Indole Test : Biochemical test to determine a bacterial species ability to convert (breakdown) tryptophan into indole. Procedure: Test 1 (4 quadrants on a card) 1. Using sterile loop pick an isolated colony from BAP (blood agar plate.) 2. Smear directly onto the reaction spread of the slide. 3. Examine test area for color change within 20 seconds. Procedure: Test 2 (liquid culture) 1. Using sterile loop pick an isolated colony from BAP (blood agar plate.) 2. Incubate bacteria in media broth. 3. Grow at 37 overnight. 4. Add ~ 5 drops of Kovac’s reagent to culture. TSI Test : [Triple Sugar Iron] agar is used to assess the ability of bacteria to ferment sugars and/or produce hydrogen sulfide. Procedure: 1. Using a sterile loop to inoculate slant from a liquid culture. 2. Press loop into the agar slant. 3. While removing loop, streak slanted side of agar with loop. 4. Grow at 37 overnight. 5. (Next day) examine samples. API Test : Broad multi panel test used for rapid characterization of bacterial species. (analytic profile species) Procedure: 1. Fill all tubes with bacterial culture. - Fill CIT, VP, and GEL entirely. - Add mineral oil ADH , LDC , ODC , H2S , and URE = anaerobic. 2. Add 5 mLdistilled water into tray, add API strip and cover with lid.
3. Incubate at 37 overnight. 4. (Next day) examine samples. Notes: Indole test Negative = yellow color Positive = red/ pink to orange color E. Coli (gram negative) positive to break down tryptophan. TSI test API test - broad multi - panel test with 20 wells. Results: Indole tested Negative - yellow color Pseudomonas (gram -) negative for indole Salmonella (gram -) negative for indole Positive - red/bright pink - orange color E. Coli (gram negative) positive to break down tryptophan. TSI test E. Coli (Gram negative) Positive - Yellow, solid slant, produces gas in bottom, no black color (no hydrosulfide gas.) E. Coli can ferment all 3 types of sugars. Salmonella (Gram negative) Positive - yellow slant in bottom, black, dark color at top of slant (ferments hydrosulfide gas.) Salmonella can ferment all 3 types of sugars and hydrosulfide gas. API Test - 20 wells in strip E. Coli (Gram - ) 1140221 ONPG yellow positive ADH yellow negative LDC yellow negative OCD red positive CIT green negative H25 colorless negative URE orange negative TDA yellow negative
Sample 1 - 5045550 IND red positive VP colorless negative GEL black negative GLU yellow positive MAN yellow positive INO blue negative SOR yellow positive RHA yellow positive SAC blue negative MEL yellow positive AMY blue negative ARA yellow negative ONPG yellow positive ADH yellow negative LDC red positive OCD yellow negative CIT green negative H25 colorless negative URE orange negative TDA yellow negative IND red positive VP red tint positive GEL No diffusion

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