Unknown Species Lab Report 2
- 1. Unknown Species: D23 LIFE206 Unknown Lab Report Lab Section: 02 Justin Alexander 4-22-2014
- 2. Series of Tables STEP # 1 for species known as D23 NAME OF TEST Gram Stain MEDIUM NA INCUBATION (if applicable) NA SPECIAL PROCEDURE(S) (if applicable) NA REAGENT(S) USED & AMOUNT (if applicable) Crystal violet, Gram’s iodine, decolorizer, safranin APPEARANCE OF RESULTS Bacteria are stained pink in color, are bacilli in shape RESULT (positive or negative, and for what) Gram-negative bacilli INTERPRETATION (what do the results mean?) This particular species lacks a thick peptidoglycan layer, which means that they cannot be BACTERIA OR SPECIES ELIMINATED All Gram-positive species; Gram-negative cocci species WHY ELIMINATED? Gram-positive species stain purple, Gram-negative cocci are different in shape POSSIBILITIES REMAINING Gram-negative bacilli STEP # 2 for species known as D23 NAME OF TEST Mobility Test MEDIUM Semi-solid agar INCUBATION (if applicable) 6 days at room temperature (RT) SPECIAL PROCEDURE(S) (if applicable) NA REAGENT(S) USED & AMOUNT (if applicable) NA APPEARANCE OF RESULTS Fuzzy along stab-line with bacterial growth towards the top of the medium RESULT (positive or negative, and for what) Bacteria tests positive for motility INTERPRETATION (what do the results mean?) This species is capable of moving through the semi-solid agar, confirming that the bacteria have flagella. BACTERIA OR SPECIES ELIMINATED All Gram-positive species; Non-motile, Gram- negative bacilli and cocci WHY ELIMINATED? The bacteria known as C11 are motile, Gram- negative bacilli POSSIBILITIES REMAINING Motile, Gram-negative bacilli
- 3. STEP # 3 for species known as D23 NAME OF TEST Catalase Test MEDIUM NA INCUBATION (if applicable) NA SPECIAL PROCEDURE(S) (if applicable) NA REAGENT(S) USED & AMOUNT (if applicable) Hydrogen peroxide APPEARANCE OF RESULTS Presence of bubbling when exposed to hydrogen peroxide RESULT (positive or negative, and for what) Positive for the presence of the enzyme catalase INTERPRETATION (what do the results mean?) This bacteria produce the enzyme catalase, which breaks down hydrogen peroxide to water and carbon dioxide. BACTERIA OR SPECIES ELIMINATED All Gram-positive species; Catalase-negative, Gram-negative, non-motile bacilli and cocci WHY ELIMINATED? The species known as C11 produces the enzyme known as catalase, and are motile, Gram-negative bacilli POSSIBILITIES REMAINING Pseudomonas aeruginosa, Pseudomonas chlororaphis, Pseudomonas fluorescens, Pseudomonas putida, Pseudomonas cichorii, and Pseudomonas syringae. STEP # 4 for species known as D23 NAME OF TEST Arginine Dihydrolase Test MEDIUM Arginine-containing medium INCUBATION (if applicable) 6 days at RT SPECIAL PROCEDURE(S) (if applicable) NA REAGENT(S) USED & AMOUNT (if applicable) 1 mL of sterile mineral oil APPEARANCE OF RESULTS The medium turned a hot pink color throughout RESULT (positive or negative, and for what) Positive for the utilization of arginine INTERPRETATION (what do the results mean?) The species in question tested positive for the use of arginine as a source for carbon and energy. BACTERIA OR SPECIES ELIMINATED P. cichorii, P. syringae WHY ELIMINATED? Both of the aforementioned species cannot use arginine as a source of carbon and energy POSSIBILITIES REMAINING P. aeruginosa, P. chlororaphis, P. fluorescens, P. putida.
- 4. STEP # 5 for species known as D23 NAME OF TEST Glucose Oxidation Test MEDIUM Hugh & Leifson’s O/F Glucose Agar INCUBATION (if applicable) 2 days at RT SPECIAL PROCEDURE(S) (if applicable) Stab inoculation with heavy inoculum REAGENT(S) USED & AMOUNT (if applicable) NA APPEARANCE OF RESULTS Yellow discoloration at the top of the medium RESULT (positive or negative, and for what) Positive for the utilization of glucose INTERPRETATION (what do the results mean?) The species in question tested positive for the use of glucose as a source of carbon. BACTERIA OR SPECIES ELIMINATED None WHY ELIMINATED? No species were eliminated. P. aeruginosa, P. chlororaphis, P. fluorescens, and P. putida all test positive for the use of glucose as a source of carbon POSSIBILITIES REMAINING P. aeruginosa, P. chlororaphis, P. fluorescens, P. putida. STEP # 6 for species known as D23 NAME OF TEST Arabinose Oxidation Test MEDIUM Hugh & Leifson’s O/F Arabinose Agar INCUBATION (if applicable) 2 days at RT SPECIAL PROCEDURE(S) (if applicable) Stab inoculation with heavy inoculum REAGENT(S) USED & AMOUNT (if applicable) NA APPEARANCE OF RESULTS Grey discoloration at the top of the medium RESULT (positive or negative, and for what) Negative for the utilization of arabinose INTERPRETATION (what do the results mean?) The species in question tested negative for the use of arabinose as a source of carbon. BACTERIA OR SPECIES ELIMINATED P. aeruginosa, P. fluorescens WHY ELIMINATED? The previously mentioned species are incapable of using arabinose as a source of carbon POSSIBILITIES REMAINING P. chlororaphis, P. putida
- 5. STEP # 7 for species known as D23 NAME OF TEST Gelatinase Test MEDIUM Nutrient Gelatin Agar Deep INCUBATION (if applicable) 2 days at 28o C SPECIAL PROCEDURE(S) (if applicable) NA REAGENT(S) USED & AMOUNT (if applicable) NA APPEARANCE OF RESULTS Substantial amount of liquid present in the medium RESULT (positive or negative, and for what) Positive for the production of gelatinase INTERPRETATION (what do the results mean?) The species in question produces the enzyme gelatinase. BACTERIA OR SPECIES ELIMINATED P. putida WHY ELIMINATED? P. putida tests negative for the production of the enzyme gelatinase POSSIBILITIES REMAINING P. chlororaphis STEP # 8 for species known as D23 NAME OF TEST Nitrate/Nitrite Reduction Test MEDIUM Nitrate broth INCUBATION (if applicable) 2 days at RT SPECIAL PROCEDURE(S) (if applicable) NA REAGENT(S) USED & AMOUNT (if applicable) 15 drops of “Nitrate A”, 15 drops of “Nitrate B” APPEARANCE OF RESULTS Broth turned bright red after the drops of nitrate B and nitrate A were added RESULT (positive or negative, and for what) Positive for nitrate reductase, and negative for nitrite reductase INTERPRETATION (what do the results mean?) The species is able reduce nitrate to nitrite, but it does not reduce nitrite to nitrogen gas or ammonia BACTERIA OR SPECIES ELIMINATED P. putida WHY ELIMINATED? P. putida tests negative for the production of nitrate reductase and nitrite reductase POSSIBILITIES REMAINING P. chlororaphis Conclusion Unknown species “D23” is Pseudomonas chlororaphis.