Lab: Lysozyme - A Defense Mechanism Flashcards
(39 cards)
Who discovered Lysozyme and in what year?
Alexander Fleming in 1922
Fleming also discovered penicillin in 1928.
In which biological fluids is Lysozyme found?
Blood, nasal secretions, tears, and most abundantly in the white of a hen’s egg.
What does Lysozyme hydrolyze in bacterial cell walls?
The bond between NAG and NAM in Peptidoglycan.
What happens to a bacterial cell when Lysozyme breaks the bond in Peptidoglycan?
The cell is no longer protected, leading to osmotic pressure causing it to burst.
Are all bacteria susceptible to Lysozyme?
No, few pathogenic species are susceptible.
What additional components do some bacteria have that shield the Peptidoglycan layer?
Teichoic acids and carbohydrates in Gram + bacteria; lipopolysaccharide layer in Gram - bacteria.
What type of bacteria is the genus Micrococcus composed of?
Non pathogenic Gram positive cocci.
What is the arrangement of Micrococcus species?
Tetrad arrangement.
Why are Micrococcus species particularly susceptible to lysozyme?
They have only peptidoglycan in their cell walls.
What is observed when lysozyme is added to a suspension of Micrococcus cells?
A clearing takes place as cells burst from osmotic pressure.
What sources of lysozyme will be used in the experiment?
Egg white and tears.
What is the control in the experiment?
Sterile saline alone.
Fill in the blank: The enzymatic function of _______ is to hydrolyze the bond between NAG and NAM.
Lysozyme
True or False: Gram - bacteria are more susceptible to lysozyme than Gram + bacteria.
False
What is the purpose of dividing the TSA plate into six sections?
To test the effect of different lysozyme sources on Micrococcus growth.
What is lysozyme?
Lysozyme is an enzyme that breaks down bacterial cell walls.
True or False: Lysozyme is found in tears and saliva.
True
What type of bacteria does lysozyme primarily target?
Gram-positive bacteria.
Fill in the blank: Lysozyme acts by hydrolyzing __________ in the bacterial cell wall.
peptidoglycan
Multiple choice: Which of the following is NOT a function of lysozyme? A) Antimicrobial activity B) Digestive enzyme C) Immune response
B) Digestive enzyme
What is the role of lysozyme in the immune system?
It helps defend against bacterial infections.
True or False: Lysozyme can be synthesized artificially.
True
Where is lysozyme predominantly found in the human body?
In secretions such as saliva, tears, and mucus.
Fill in the blank: Lysozyme is classified as a __________ enzyme.
hydrolase
