P1 | Bacterial Cell Components (LECTURE) Flashcards
referred to as the peptidoglycan [main component], or murein layer
CELL WALL
other components of the cell wall?
(PB,P)
- Phospholipid bilayer
- protein
This structure gives the bacterial cell shape and strength to withstand changes in environmental osmotic pressures that would otherwise result in cell lysis.
CELL WALL
Gives structure to the shape of the cell
CELL WALL
Gives strength; resists any mechanical disruption
CELL WALL
Acts as an osmotic barrier to the passage of larger substances
CELL WALL
Location of electron transport chain = ?
energy is generated
protects against mechanical disruption of the cell
CELL WALL
offers some barrier to the passage of larger substances.
CELL WALL
Differential staining method → cell wall ang target
- Gram positive: (color)
- Gram Negative: (color)
**Gram Stain Reaction
**
- Purple
- Red
4 COMPONENTS OF GRAM STAINING TECHNIQUES
(C,G.I,A,S)
- Crystal Violet
- Gram’s Iodine
- Acetone/Alcohol
- Safranin
- Crystal Violet:
- Gram’s Iodine:
- Acetone/Alcohol:
- Safranin:
- Primary stain
- Mordant [strengthen the affinity of the stain to the bacterial cell wall]
- Decolorizer [95% ethanol or ethyl alcohol]
(Gram positive – purple, Gram negative – colorless [thin peptidoglycan]) - Secondary Stain/Counterstain
Gram (+): Purple, Gram (-): Pink
Before the staining process, the bacterial cell wall is?
colorless
2 FIXATION METHOD:
- Physical [heat]
- Chemical [methyl alcohol]
gel-like substance that either contains enzymes that are degradative.
- can only be seen at the gram negative
Periplasmic Space
important for invasion; capable of degrading the host’s surface;
Degradative enzymes
_______ have greater virulence
(G.N.O)
Gram Negative organisms
Assists in the capture of nutrients from the environment
Degradative enzymes
channel for water and other molecules that open and close for the substances’ entry
porin
Has a very thick protective peptidoglycan (murein) layer
GRAM POSITIVE CELL WALL
provide rigidity to the cell wall by attracting magnesium and calcium
(T.A)
Teichoic acid
acts as regulator of autolytic wall enzyme, regulate the antigenic properties (has antigen)
(L.A)
lipoteichoic acid
Stimulate the immune response of the host
(A.P)
Antigenic properties
Autolytic wall enzyme
example:
(MC)
muramiclase (anti-microbial enzyme)