Mcb 3020C Medical Micro Test 3

Front 1

Mutualism?

Back 1

-both host and microbe benefit

Front 2

Commensalism?

Back 2

-microbe causes no damage to host

Front 3

Parasite (parasitism)?

Back 3

-microbe causes damage to host (parasite often refers to eukaryotic invaders)

Front 4

Pathogenic relationship?

Back 4

-microbe causes damage to host (pathogen)

Front 5

Synergistically?

Back 5

- capable of working together; two microorganisms are synergistic if they are able to produce a host response greater than the sum of the effects they produce when acting alone

Front 6

Communicable?

Back 6

-able to be transmitted between hosts

Front 7

Disease reservoir?

Back 7

-a natural source of disease agent.

Front 8

The quantitative measure of degree pathogenicity is called

Back 8

virulenc

Front 9

Infestation?

Back 9

Presence of organism; not necessarily growing & reproducing

Front 10

Places where normal flora do not exist?

Back 10

brain, blood, cerebrospinal fluid, muscles

Front 11

slime layer also known as?

Back 11

glycocalyx layer

Front 12

Enterotoxic strains of Escherichia coli express fimbrial proteins called _________that adhere specifically to cells in small intestine.

Back 12

CFA (Colonization factor antigens)

Front 13

2 elements of virulence?

Back 13

Invasiveness and toxigenicity

Front 14

________catalyzes the breakdown of ________, the substance that cements the human cells together

Back 14

Hyaluronidase

Front 15

Hyaluronidase - This is also called the spreading factor because it catalyzes the breakdown of hyaluronic acid, the substance that cements the human cells together. This allows the bacterial cells to spread through tissue causing a condition known as _______

Back 15

cellulitis

Front 16

Coagulase?

Back 16

- This enzyme catalyzes the conversion of fibrinogen to fibrin with resultant clot formation.

Present in pathogenic Staphyloccus.

Front 17

Fibrinolysin?

Back 17

- This catalyzes the conversion of plasminogen to the fibrinolytic enzyme plasmin. Thus it acts opposite of coagulase.

Front 18

In Staphylococcus aureus, the gene for fibrinolysin is on _________ and is expressed during _________.

Back 18

a bacteriophage

lysogeny

Front 19

Production of excessive amounts of ______ allow bacteria to penetrate fatty tissue with the consequent formation of ________.

Back 19

lipase

abscesses

Front 20

This enzyme catalyzes the degradation of collagen, a protein found in tendons, nails and hair

Back 20

Collagenase

Front 21

________ cause lysis of white blood cells;

Present in?

Back 21

Leukocidins

Staphyloccus aureus (puss = pyogenic)

Front 22

2 examples of fibrinolytic enzymes?

Back 22

Streptokinase and Streptodornase: actually fibrinolytic enzymes

Front 23

destroys red blood cells & other tissue cells.

Back 23

Lecithinase

Front 24

lyse red blood cells

Back 24

Hemolysins:

Front 25

What aspect of virulence does LD50 test?

Back 25

Toxicity not invasiveness

Front 26

Three categories of exotoxins

Back 26

Cytolytic toxins

AB Toxins

Superantigenic toxins

Front 27

Cytolytic toxins (include hemolysins):

Back 27

damage cell membranes, causing cell lysis & death (also are subcategory of cytotoxins, next slide

Front 28

A-B toxins:

Back 28

B promotes specific binding of toxin to host cell receptor (allows transfer of A (toxic part) across targeted cell membrane).

Front 29

Superantigen toxins:

Back 29

Stimulate large numbers of immune lymphocytes and causes systemic as well as inflammatory responses. Extensive inflammation & tissue damage

Front 30

example of a cytolytic toxin

Back 30

alpha toxin of staph

Front 31

Neurotoxins: ?
Examples:?

Back 31

inhibit nerve transmission

tetanus and botulinum toxin

Front 32

Enterotoxins:?
Examples: ?

Back 32

alter permeability of intestinal epithelium

Cholera and Staph aureus food poisoning enterotoxin (also superantigen)

Front 33

Example of AB toxin? Function?

Back 33

Diptheria toxin is an A-B toxin that inhibits a cell function: protein synthesis; catalyzes ADP-ribosylation of elongation factor 2 (EF-2) and it no longer aids the transfer of amino acids to growing polypeptide chain. Ends protein synthesis

Front 34

Diptheria is present in?

Back 34

Diptheria toxin is formed only by strains of Corynebacterium diptheriae cells that are lysogenized by phage beta.

Front 35

Example of AB toxin?

Back 35

Anthrax

Front 36

Botulinum toxin

Back 36

Toxin binds to presynaptic terminal membranes at nerve-muscle junction, blocking the release of acetylcholine required for transmission of nerve impulse to muscle.
Muscle contraction inhibited & have flaccid paralysis

Front 37

Tetanus toxin

Back 37

blocks release of glycine, a factor that induces muscle relaxation
Relaxation signal is blocked & paired muscles both contract
Spastic paralysis, twitching paralysis

Front 38

Enterotoxins

Back 38

Exotoxin that alters permeability of intestinal epithelium; causes massive secretion of fluid into the intestinal lumen causing diarrhea

Front 39

Gram-negative bacteria produce lipopolysaccharides as part of the outer layer of their cell envelope. ________ portion responsible for toxicity, _________ makes complex water soluble & immunogenic.

Back 39

Lipid A

polysaccharide fraction

Front 40

Stimulates host cells to release proteins called ________ causing fever

Back 40

endogenous pyrogens