Structure + Function

Question 1

peptidoglycan

Answer 1

Fx: Gives rigid support, protects against osmotic pressure
Composition: Sugar backbone with peptide side chains cross linked by transpeptidase

Question 2

Q1: Cell wall/ Cell Membrane
Q2: In what type of pathogen type are they present ?

Answer 2

Q1:
Fx: Major Surface antigen
Composition: Peptidoglycan for support ( Lipoteichoic Acid)
Q2: This is seen in Gram Positive organisms only

Question 3

Lipoteichoic acid will induce what immunomodulators?

Answer 3

TNF and IL-1

Question 4

Outer membrane: What organism type?

Answer 4

Gram (-) only

Question 5

Outer Membrane: Fx and composition

Answer 5

Fx: Site of endotoxin (LPS) –> Major surface antigen recognized but the body
Composition:
- Lipid A

Question 6

Lipid A:
What does it induce?
What is its antigenic subunit?

Answer 6

Lipid A induces IL-1 and TNF

the antigenic subunit: O Polysaccahride

Question 7

Plasma Membrane

Answer 7

Fx:
Site of oxidative and transport Enzymes
Composition: Lipoprotien bilayer

Question 8

Ribosome

Answer 8

Fx: Protein Synthesis
Composition: 50S and 30S

Question 9

Periplasm

Answer 9

Fx:
Space between the cytoplasmic membrane and the outer membrane in gram (-) bacteria
Comp: Contains many hydrolytic enzymes including Beta-lactamases

Question 10

Capsule

Think about the one exception to the rule?

Answer 10

Fx: Protects against opsonization and phagocytosis
Composition:
Polysaccahrides, with the exception of Bacillus anthraces –> it is made of a polypeptide layer

Question 11

Pilus/Fimbria

Answer 11

Fx:
-Mediates adherence of bacteria to cell surface
-Sex pious forms attachment between 2 bacteria during conjugation
Composition: Glycoprotein

Question 12

Flagellum

Answer 12

Fx:
Motility
Comp: protein –> typically microtubules/microfilaments

Question 13

Spore

Answer 13

Fx: Resistant to dehydration, heat and chemicals
(aka --> ridiculously hard to kill)
Composition: 
- Keratin like coat
- dipicolinic acid
- peptidoglycan

Question 14

Plasmid

Answer 14

Fx: Contains a variety of genes for antibiotic resistance, enzymes, and toxins
Comp: DNA

Question 15

Glycocalyx

Answer 15

Fx: Mediates adherence to surfaces, especially foreign surfaces
Comp: Polysaccahride

Question 16

Where would you most expect to see a pathogen with a glycocalyx?

Answer 16

Fomites, probably in the hospital.

this is a huge place for these bugs to grow (IV lines, indwelling catheters, metal implants….)

Question 17

List all the parts of the Gram (+) bacterium from the cytoplasm to environment

Answer 17

• Cytoplasmic membrane
• Cell Wall: Peptidoglycan layer that has Structural proteins imbedded in it: Flagella, Lipoteichoic acid, and pili
• Capsule

Question 18

List all the parts of a Gram (-) bacterium from the cytoplasm to environment

Answer 18

• cytoplasmic membrane
• periplasm: imbeded flagellar base and base for pious
• SMALL peptidoglycan layer
• Outer cytoplasmic membrane: composed of endotoxin (LPS)
• Capsule