Bacterial Structures

Question 1

Peptidoglycan

Answer 1

Gives rigid support, protects against osmotic pressure

Sugar backbone with peptide side chains cross-linked by transpeptidase

Question 2

Cell wall

Answer 2

Major surface antigen

Peptidoglycan for support. Lipoteichoic acid (unique to gram+) induces TNF and IL-1

Question 3

Outer membrane (gram negatives)

Answer 3

Site of endotoxin (LPS); major surface antigen

Lipid A induces TNF and IL-1
O polysaccharide is the antigen

Question 4

Plasma membrane

Answer 4

Site of oxidative and transport enzymes

Phospholipid bilayer

Question 5

Ribosome

Answer 5

Protein synthesis

50S and 30S subunits

Question 6

Periplasm

Answer 6

Space between the cytoplasmic membrane and outer membrane in gram- bacteria

Contains many hydrolytic enzymes, including B-lactamases

Question 7

Pilus/fimbrae

Answer 7

Mediate adherence of bacteria to cell surface; sex pilus forms attachment between 2 bacteria during conjugation

Glycoprotein

Question 8

Flagellum

Answer 8

Motility

Protein

Question 9

Spore

Answer 9

Resistant to dehydration, heat, and chemicals

Keratin-like coat; dipicolinic acid; peptidoglycan

Question 10

Plasmid

Answer 10

Contains a variety of genes for antibiotic resistance, enzymes, toxins

DNA

Question 11

Capsule

Answer 11

Protects against phagocytosis

Organized, discrete polysaccharide layer (except Bacillus anthracis, which contains D-glutamate)

Question 12

Glycocalyx

Answer 12

Mediates adherence to surfaces, especially foreign surfaces (indwelling catheters)

Loose network of polysaccharides