Module 3 pt. 3 Flashcards
Counters the effects of osmotic pressure
Provides attachment sites for bacteriophages (virus that eats bacteria)
Provide a rigid platform for surface appendages
Sites of antigenic determinants of the cell surface
Resist antibiotics
Cell wall
Responsible for the rigidity of the bacterial cell wall, only macromolecule only found in bacteria
Peptidoglycan
Types of surface appendages (5)
Glycocalyx (Capsule, slime wall)
S-layer (Surface proteins)
flaghella
fimbriae
pili
Arrangement of bacteria (3)
Diplo - 2 beside
Staphylo - shaped like grapes
Strepto - In a line
No net movement of water
Water moves into the cell and may cause the cell to burst it if the wall is weak or damaged
Water moves out of the cell, causing its cytoplasm to shrink
Isotonic solution
Hypotonic solution (osmotic lysis)
Hypertonic solutiom (plasmolysis)
Peptidogylcan aka ___
is composed of alternating chains of
___ and ___ which is cross linked by ___ chains
Responsible for the rigidity of the bacterial cell wall and the determination of cell shape
Murein
Mucopeptide
N-acetyl glucosamine (NAG)
N-acetyl Muramic Acid (NAM)
peptide chains
Serves as the backbone of the peptidoglycan molecule
B-1-4-glycosidic bond
Different bacteria species, different amino acid composition
Tetrapeptide
Gram positive bacteria cell wall components (2)
-Teichoic acid
- Peptidoglycan cell wall
Gram-negative bacteria cell wall components (5)
O antigen
Outer membrane
Murein lipoprotein
Peptidoglycan cell wall
Periplasmic space
20-80 nm thick Gram positive cell wall percentages (2)
It is fully permeable to many substances
90% peptidoglycan
10% Teichoic acid
These polymers play crucial roles in cell shape determination
regulation of cell division
Other fundamental aspects of Gram-positive bacterial physiology
Anionic glycopolymers
Interwoven in the cell wall of the gram-positive are ___ and ___ which are covalently bonded to NAM
Teichoic acid
Lopoteichoic acids
gram negative cell wall outer membrane is composed of (2)
Phospholipids
Lipopolysaccharide (LPS)
gram negative cell wall outer membrane is composed of (2)
Phospholipids
Lipopolysaccharide (LPS)
___ are outer membranes have a specialized channel for low molecular weight substances
___ translocate proteins produced to the outside of outer membrane
Porins
Secretion systems
Regions of the LPS (3)
Polysaccharide determining O antigen
Core Polysaccharide
Glycolipid portion / Lipid A - Disaccharide diphosphate, fatty acids
Causes a form of septic shock from which there is no direct treatment
Endotoxin - lipopolysaccharide
Side chain portion of LPS directed away from the membrane
Chains of sugar molecules with varying composition and lengths
Used to identify certain species or strains
O-Antigen
Responsible for the toxic properties of the G-bacteria (endotoxin)
Anchors the LPS in the bilayer
Hints at the presence of invading bacteria
Lipid A
Gel-like fluid (periplasm)
Protein-filled (secreted proteins)
Very active area of cell metabolism
contains digestive enzymes and transport proteins
mostly observed among G- bacteria
Periplasmic space
Interferes with peptidoglycan synthesis
Bunds to proteins involved in cell wall synthesis
Prevents cross-linking
Most effective against G+ bacteria
Derivatives can pass through porin channels
Penicillin
Interferes with peptidoglycan synthesis
Found in many body fluids
Breaks bond between the NAM and NAG molecules
Lysozyme
LONG PPT
Lipopolysaccharide
Outer Membrane
Negative
Gram
Positive
Peptidoglycan (thick)
Teichoic acid
