Post Lab Flashcards
Observation for Pineapple glass 3
Gelatin does not form liquid
Observation for Pineapple glass 2
Gelatin breaks down and forms liquid
Observation for Pineapple glass 1
No changes
They are capable of hydrolyzing peptide bonds and are also referred to as peptidases, proteases or proteinases.
Proteolytic Enzymes
Proteolytic Enzymes belongs to the hydrolase class of enzymes (T/F)
True (Hydrolase)
Action of Proteolytic is essential to:
Digestion
Protein Turnover
Cell Division
Blood-clotting cascade
Signal Transduction
Generic name given to the set of derived
endopeptidases belonging to members of the Bromeliaceae family, being able to break the peptide bond, separating proteins and amino acids
Bromelain
Scientific name of Pineapple
Ananas comosus
Optimum Temperature and pH of enzyme
bromelain
50 C
pH 7.0
Egg albumin solution Observation
Firm liquid
Beaten egg whites Observation
Bubble formation
Heated egg whites Observation
Solidifies
Egg albumin solution, alcohol Observation
Solidifies
Egg albumin solution and vinegar Observation
Solidifies
Refers to the physical changes that take place in a protein exposed to abnormal conditions in the environment.
Protein Denaturation
Causes of Protein Denarturation
Heat (Temperature)
Acid
Alcohol
Mechanical Agitation
High Salt Concentration
When a protein denatures, its complicated folded structure _______, and it becomes just a __________ of amino acids again.
Unravels
Long strand
What Protein structures do weak chemical forces hold
Tertiary Protein Structures
Secondary Protein Structures
It is dependent of its shape, so denatured proteins are no longer functional.
Protein Function
During cooking the applied heat causes proteins to ________
Vibrate
This destroys the weak bonds holding proteins in their complex shape
Applied (Heat)
The unraveled protein strands then stick together, forming an
Aggregate (or network)
What is biuret reagent made of
Copper sulfate CuSO4 (Strong base)
Test for peptide bonds
Biuret’s Test
Positive result for Biuret Test
Albumin – violet
Peptone – violet
Gelatin – violet
Casein – violet
Amino Acids – blue
How many peptide bonds are required for the formation of violet complex?
Two peptide bonds are at
least required
Ninhydrin Reacts with ______-
Alpha - Amino acids (–NH2)
Color given by Ninhydrin when it reacts with α-amino acids
purple colored complex
In Ninhydrin, Tyrosine and Tryptophan results in a purple color meaning they are?
α-amino acids
Ninhydrin positive result for Proline and Hydroxyproline
yellow
Test used to detect amino acids containing an
aromatic nucleus
Xanthoproteic Test
Positive color result for Xanthoproteic test
Tyrosine - Yellow
Tryptophan - Yellow
Phenylalanine - Yellow
It is the only amino acid containing a phenol group
Tyrosine
It is a hydroxyl group attached to a benzene ring
Phenol group
Test specific for tyrosine, the only amino
acid containing a phenol group,
Millon’s Test
Positive color result for tyrosine
Tyrosine - Brick Red
Phenol Solution - Brick Red
specific for free Arginine or proteins
containing Arginine
Sakaguchi Test
Arginine belongs to what group?
Guanidine group
Positive color result for Sakaguchi test
red-coloured complex
Specific for Tryptophan in proteins
Hopkins-Cole Test
Sulphuric acid in presence of mercuric sulphate
oxidizes the _________ of tryptophan
Indole nucleus
Positive result for Hopkins-Cole Test
violet-purple colored complex
