Act 9 Gege Flashcards
- used for CHO fermentation
- Air space in the smaller test tube indicates GAS production in LACTOSE BROTH
Durham fermentation tube
-Bacteria used in converting one molecule of glucose into two molecules of lactic acid.
- used in fermenting milk and milk products
Homolactic fementers
Yields carbon dioxide and ethanol + lactic acid
- leuconostoc , weissella
Heterolactic fermenters
-Pathway of glycolysis
- used in homolactic acid bacteria to produce lactic acid
- used by saccharomyces (yeast) to produce ethanol and carbon dioxide
Embden-meyerhof pathway
Catabolize glucose to pyruvate
- occurs only in prokaryotes
- generally utilized by gram negative bacteria
Entner-doudoroff pathway
These are the end products from the breakdown of glucose:
-fermentation of glucose
- production of carbon dioxide or mixture of hydrogen and carbon dioxide
- hydrogen is insoluble and is detected by the bubble formation in durham tube
Three sugars of TSI:
- lactose
- sucrose
- glucose
What does TSI detect
Early detection of coliform bacteria that ferments sucrose more rapidly than lactose
What does TSI red color indicate
Alkalinization (K)
What does TSI yellow color indicate
Acidity (A)
What does it mean when the color changes from red to yellow
Acid production
What does it mean when air bubbles or splitting of agar in the butt appear
Gas production
What does the black color in the butt portion indicate
H2S
This results from the reaction between the iron salts of ferrous sulfate and ** ferric ammonium citrate** forming an insoluble black precipitate of ferrous sulfide
H2S
(IMViC) detects the production of —- , Reagent: KOVAC’s; RESULTS: pink(+), yellow(-)
Indole
(IMViC) detects strong acid from glucose; Reagents: —- ; RESULTS: red(+), yellow (-)
Methyl red
(IMViC) Formation of acetyl methyl carbinol acetoin from glucose fermentation., Reagents: Alphanaphthol and KOH; RESULTS: red/brown (+), yellow(-)
Voges-proskauer
(IMViC) —- as the only source of carbon, Reagents: Bromothymol blue; Results: blue (+), green(-)
Citrate
This is employed in the identification of enterobacteriaceae
IMViC reactions
Test that identifies the ability of the organism to used citrate as its sole source of carbon
Citrate Utilization Test
(IMViC) ++—
Escherichia coli
(IMViC) -+—
Shigella spp.
(IMViC) -+-+
Salmonella spp., Proteus mirabilis, Citrobacter freundii
(IMViC) —++
Klebsiella spp.
