Bacterial Unknown Day 3

Bacterial Unknown Day 3 - 1 Identification of Bacteria:...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1 Identification of Bacteria: Unknowns Day#3 Physiological Characteristics: Oxidation and Fermentation Tests Materials: (per student ) 1 Glucose broth (10ml) (Ex 5-2) 1 Sucrose broth (10ml) (Ex. 5-2) 1 Lactose broth (10ml) (Ex 5-2) 2 MRVP media (5ml)(Ex 5-4) 1 Mannitol broth (10ml) (Ex 5-2) 1 Nitrate broth (5ml)(Ex 5-7) The MRVP media will be incubated in a separate rack since the VP test requires a 5-day incubation at 37 o C. All other media will be incubated together in the racks provided for 48 hours at 37 o C. Physiological Characteristics: Oxidation and Fermentation Tests Oxidase Test (Ex 5-6) Tests for: presence of cytochrome c or cytochrome a3 which is part of the electron transport chain Reagent: 1% solution of tetramethyl-p-phenylenediamine dihydrochloride positive control Pseudomonas aeruginosa negative control Escherichia coli Students will perform the Oxidase Test on their Unknown bacteria by inoculating a piece of filter paper as indicated in the figure and then adding drops of the Oxidase test reagent. The controls will be available on TSA plates. Results: positive result : dark blue/purple color change within 15 seconds negative result : no color change within 15 seconds P. aeruginosa Unknown E. coli Physiological Characteristics: Oxidation and Fermentation Tests Sugar Fermentation Tubes (with Durham tubes) Tests for: the fermentation of sugars: glucose, lactose, mannitol, and sucrose Reagent :- pH indicator : Phenol Red for detecting acid production upon fermentation; pH of media will drop as acid is produced; (red for pH >7 and yellow for pH <7)- inverted tube (Durham tube): for detecting gas production upon fermentation; if a bubble appears in the tube, then gas was produced Results :- positive : yellow color change for sugar fermentation; bubble in the tube for gas production- negative : red color for no sugar fermentation; no bubble in the tube for no gas production 2 Physiological Characteristics: Oxidation and Fermentation Tests Nitratase Test: Tests for: the presence of nitrate as an electron acceptor in anaerobic respiration and the...
View Full Document

Page1 / 4

Bacterial Unknown Day 3 - 1 Identification of Bacteria:...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online