Lesson 7 : Laboratory Tests for Enzymes Flashcards
Enzymes are ___________ responsible for ____________ many biological processes.
proteins
speeding up
Enzymes act as _____________ by lowering the _______________ required for a reaction.
catalysts
activation energy
Enzymes are also _________ in their action, it can act on one substrate or one class of related analogs of substrate because the _____________ of the enzymes complement to the __________ and _________ of the substrate.
specific
active site
geometry and polarity
Factors that affect the enzyme activity such as ___________, ____________, ____________, and _______________ must be considered in characterizing the enzyme in its native form and inhibition activity of the test compound against the enzyme.
enzyme concentration, temperature, pH of the working buffer, and presence of the inhibitor compounds
Reagents for Catalase Enzyme Activity
Hydrogen Peroxide (H2O2)
Distilled Water
Vinegar (Source of Acetic Acid)
Potato
Reagents for Enzyme
Inhibition Assay
Urea Solution
Bromothymol Blue
Mercuric Chloride
Distilled Water
Urease
What are the things we can learn from the Catalase Enzyme Activity
Enzyme activity of Catalase from Potato
Increase or Decrease in Surface Area
Changes in Temperature
Changes in pH
A very common enzyme that is present in almost all organisms that are exposed to oxygen.
Catalase
Catalase is also found in __________.
plants
What Happens to Hydrogen Peroxide when Catalase is Added?
Catalase is an enzyme that catalyzes the reaction by which hydrogen peroxide is broken down to water and oxygen.
This breaking down of hydrogen peroxide to water and oxygen is physically seen as ‘______________’ or _________________.
bubbling
formation of bubbles on the top of the solution
Effect of Changes in temperature and pH to Enzymes
Recall that enzymes are protein in nature. Hence, the same factors that denature proteins also denature enzymes.
Effect of Increase or Decrease in Surface Area
Increasing surface area also increases enzymatic activity.
Catalase has an optimum temperature of ____. Going lower or above the optimum temperature may result in ____________ of the enzyme.
37C
denaturation
If the pH level is lower than __ or higher than __, the enzyme becomes ___________ and loses its structure.
7, 11
denaturated
Enzyme Inhibition Assay
In this experiment we used ___________ as the enzyme inhibitor for the enzyme ____________.
_______________ was used as the pH indicator for the solution.
Mercuric Chloride
urease
Bromothymol Blue
What is Bromothymol Blue
This 0.1% aqueous bromothymol blue solution (also known as Bromothymol Blue)
Bromothymol blue changes color to determine pH of a solution:
Yellow
Blue
Yellow - Acidic
Blue - Alkaline
Mercury is a ____________ that has been used for centuries as a medicine and a poison.
heavy metal
Mercury ions from mercuric chloride can produce its toxic effects by ____________, ____________, and _______________.
protein precipitation, generalized corrosive action, and enzyme inhibition
Binding of mercury can change the ___________ of the enzyme and ___________ its activity.
shape
block
What are some of the enzymes inhibited by mercury
urease,
acetylcholinesterase,
catalase,
dipeptidyl peptidase (CD26),
amylase,
lipase,
lactase and
glucose-6-phosphatase.
Urea is the product of ______________ of _______________. Urease will ____________ the ___________of urea into _____________ and ______________. Ammonia has a pH of __-___-___. The formation of ammonia shifts the pH of the solution to __________.
decarboxylation
amino acids
catalyze the hydrolysis
ammonia and carbon dioxide
11-13
alkaline
