Biochemicals Flashcards
What are the end products of CHOs?
Acids
What makes alkaline end products?
Peptones
What order will organisms utilize CHOs and peptones?
CHOs first. peptones next
Principle: to determine the ability of an organism to produce large amounts of acid or neutral end products from glucose fermentation
Methyl Red test
Two types of fermentation
- Mixed acid fermentation
- Butylene glycol fermentation
Methyl Red test
- What is in the media?
Glucose
Methyl Red test
- Reagent
Methyl red indicator (single drop at a time)
Methl Red test
- Results
Pos: red
Neg: yellow
Methyl Red test
- Substrate(s)
- End product
Substrate: glucose
End product: acid
Principle: to detect presence of the neutral end product acetone (acetylmethylcarbinol) resulting from the fermentation of glucose
Voges-Proskauer (VP) test
VP test
- Results
Pos: pink (butylene glycol fermentation)
Neg: no change (straw colored)
VP test
- Substrate(s)
- End product
Substrate: glucose
End product: acetoin (acetylmethylcarbinol)
VP test
- Reagent
Alpha napthol and KOH
VP test
- What is in the media?
Glucose
Principle: to determine if an organism is capable of utilizing citrate as its sole source of carbon
Sodium Citrate (Citrate) test
Citrate test
- What is in the media?
Citrate (inoculate slant)
Citrate test
- Substrate(s)
- End products
Substrate: citrate
End product: carbon?
Citrate test
- Reagent
None
Citrate test
- Results
Pos: blue
Neg: no change (green)
Principle: to detect an organism’s ability to oxidatively deaminate phenylalanine to phenylpyruvic acid
Phenylalanine deaminase
Phenylalanine deaminase
- What is in the media?
DL-phenylalanine agar (inoculate slant)
Phenylalanine deaminase
- Reagent
FeCl3 (ferric chloride)
Phenylalanine deaminase
- Substrate(s)
- End products
Substrate: deaminate phenylalanine
End product: phenylpyruvic acid
Another name for phenylalanine deaminase test
TDA test in some methods (API)
Phenylalanine deaminase
- Results
Pos: dark green slant (fades after several minutes)
Neg: no change (yellow from reagent)
Principle: to detect whether an organism can split indole from the amino acid tryptophane
Indole test
Indole test
- What is in the media?
Peptone or tryptone broth (little or no glucose)
Indole test
- Substrate(s)
- End product
Substrate: amino acid tryptophane
End product: indole
Indole test
- Reagent (Ehrlich’s)
- Reagent (Kovac’s)
SAME IN BOTH:
P-dimethylaminobenzaldehyde-HCl in ethyl alcohol
Indole test
- Results
Pos: red (middle layer in Ehrlich’s test, top layer in Kovac’s)
Neg: no change (yellow)
Two procedures for indole test
Ehrlich’s and Kovac’s